Interview with Aitor Calero of Directo al Paladar

Aitor Calero writes for the popular Spanish cooking and nutrition blog, Directo al Paladar ("straight to the palate").  We did a written interview a while back, and he agreed to let me post the English version on my blog.  The Spanish version is here and here.

Without further ado, here it is:

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Beyond Ötzi: European Evolutionary History and its Relevance to Diet. Part III

In previous posts, I reviewed some of the evidence suggesting that human evolution has accelerated rapidly since the development of agriculture (and to some degree, before it).  Europeans (and other lineages with a long history of agriculture)  carry known genetic adaptations to the Neolithic diet, and there are probably many adaptations that have not yet been identified.  In my final post in this series, I'll argue that although we've adapted, the adaptation is probably not complete, and we're left in a sort of genetic limbo between the Paleolithic and Neolithic state. 

Recent Genetic Adaptations are Often Crude

It may at first seem strange, but many genes responsible for common genetic disorders show evidence of positive selection.  In other words, the genes that cause these disorders were favored by evolution at some point because they presumably provided a survival advantage.  For example, the sickle cell anemia gene protects against malaria, but if you inherit two copies of it, you end up with a serious and life-threatening disorder (1).  The cystic fibrosis gene may have been selected to protect against one or more infectious diseases, but again if you get two copies of it, quality of life and lifespan are greatly curtailed (2, 3).  Familial Mediterranean fever is a very common disorder in Mediterranean populations, involving painful inflammatory attacks of the digestive tract, and sometimes a deadly condition called amyloidosis.  It shows evidence of positive selection and probably protected against intestinal disease due to the heightened inflammatory state it confers to the digestive tract (4, 5).  Celiac disease, a severe autoimmune reaction to gluten found in some grains, may be a by-product of selection for protection against bacterial infection (6).  Phenylketonuria also shows evidence of positive selection (7), and the list goes on.  It's clear that a lot of our recent evolution was in response to new disease pressures, likely from increased population density, sendentism, and contact with domestic animals.

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Junk Free January

Last year, Matt Lentzner organized a project called Gluten Free January, in which 546 people from around the world gave up gluten for one month.  The results were striking: a surprisingly large proportion of participants lost weight, experienced improved energy, better digestion and other benefits (1, 2).  This January, Lentzner organized a similar project called Junk Free January.  Participants can choose between four different diet styles:

1. Gluten free
2. Seed oil free (soybean, sunflower, corn oil, etc.)
3. Sugar free
4. Gluten, seed oil and sugar free

Wheat, seed oils and added sugar are three factors that, in my opinion, are probably linked to the modern "diseases of affluence" such as obesity, diabetes and coronary heart disease.  This is particularly true if the wheat is eaten in the form of white flour products, and the seed oils are industrially refined and used in high-heat cooking applications.

If you've been waiting for an excuse to improve your diet, why not join Junk Free January?

Gluten-Free January Survey Data, Part I: Demographics and Limitations

Thanks to Matt Lentzner for organizing Gluten-Free January, and everyone who participated and completed the survey, we have a nice data set illustrating what happens when a group of people stop eating gluten for a month. Janine Jagger, Matt and I have been busy analyzing the data, and I'm ready to begin sharing our findings.

GFJ had over 500 participants, 527 of which received the survey and 279 of which completed the survey at the end of the month. Of those who received the survey, 53 percent completed it. I think these are respectable numbers for a survey of this nature, and it reflects the conscientious nature of the people who participated in GFJ.

Demographics

Although respondents were primarily from the United States, I'm happy to say that the data represent 18 different nationalities:

Respondents represented a diversity of ages, the largest group being 30-39 years old, with similar numbers in the 20-29 and 40-49 year groups.
Respondents were just under 2/3 women.

Respondents represented a variety of weights, but the sample was biased toward lean people, in comparison with the general population. There were not many obese participants.
Overall, I was pleased to see that the demographics were quite diverse, particularly in the age and gender categories.

Limitations

There are a few caveats to keep in mind when interpreting the survey results:

1. GFJ participants do not represent a random cross-section of the population at large. They represent primarily health-conscious individuals who were motivated enough to make a substantial dietary change. In addition, many of the people who participated probably did so because they already suspected they had a problem with gluten.
   
2. The survey response rate was 53%. Although I think that's a reasonable number considering the circumstances, it leaves open the possibility that survey responders differ from non-responders. It's conceivable that participants with better adherence and better outcomes were more likely to complete the survey than those who did not adhere to the diet or had neutral or unfavorable outcomes, despite our efforts to encourage everyone to complete the survey regardless of adherence or outcome. So the results could be biased toward positive outcomes, meaning that we will need to see a strong effect for it to be believable.
   
3. This was a non-blinded diet trial without a control group. There's no way to know how much of the effect was due to avoiding gluten per se, how much was due to overall changes in diet patterns, and how much was a placebo effect.
   

With that in mind, what can we take from the survey data? I feel that we can use it to answer the following question: "what is likely to happen when a motivated, health-conscious person decides to avoid gluten for a month?" And I think we can also use it to generate (but not test) hypotheses about the effects of eating gluten on the general population.

Gluten-Free January Raffle Winners Selected!

Raffle winners have been selected and shirts are on their way. You know who you are. Thanks to everyone who participated and filled out the survey! For those who didn't, there's always next year.

Janine Jagger, Matt Lentzner and I are busy crunching the mountain of data we collected from the GFJ survey. We got 279 responses, which is remarkable for a survey of this nature.

Stay tuned for data!

My Gluten-Free January

I've been avoiding most gluten, particularly wheat, for over a year now. I never had obvious symptoms that I could clearly link to eating wheat, although I had my suspicions. I've made many changes to my diet over the last decade, and I feel much better than I did ten years ago, but it's hard to disentangle all the factors. I don't think I ever went an entire month without eating any gluten at all before this January. After posting Matt Lentzner's challenge to go gluten-free this January, I felt obligated to do it myself, so I signed up!

I succeeded in avoiding all gluten for the month of January, even though it was a pain at times. I felt good before January, and didn't start with any health or body weight problems, so there wasn't much to improve. I also felt good while strictly avoiding gluten this January, perhaps a little better than usual but it's hard to say.

At the end of the month, I did a blinded wheat challenge using the method I described in a previous post, which uses gluten-free bread as the placebo (1). I recorded my blood sugar at 30 minute intervals after eating the bread, and recorded how I felt physically and emotionally for three days after each challenge.

The result? I think the bread gave me gas, but that's about it. I'm not even positive that was due to the wheat. My energy level was good, and I didn't experience any digestive pain or changes in transit time. There was no significant difference in my blood glucose response between the bread and the gluten-free bread.

I decided that I didn't have any symptoms, so I celebrated by having a porter (1) with friends a few nights later. I slept poorly and woke up with mild digestive discomfort and gas. Then I ate wheat later in the week and slept poorly and got gas again. Hmmm...

Some people might say that the body adapts to any food, and wheat is no different. Go without it for a while, and the body has a tough time digesting it. But I can go for weeks without eating a potato, a chicken thigh or broccoli, and all will digest just fine when I eat them again.

I'm pretty sure I don't have a severe reaction to gluten. I think I'm going to stick with my mostly gluten-free habits, and eat it occasionally when I'm offered food in social situations.

Did anyone else do a blinded wheat challenge? Describe it in the comments!

Gluten-Free January Raffle!

Hi, Gluten-Free January participants. Matt, Janine and I have collected about 200 survey responses at this point. So far, the results are very interesting! But we want to get as many responses as possible, because the more responses we get, the more informative the data will be for all of us. So please fill out the survey Matt sent you by e-mail, no matter what your results were, and no matter whether you stuck with the diet or not! The survey is strictly about your GFJ experience, not investment opportunities, timeshares, ShamWows or anything else. It will take you less than 5 minutes, and it's totally anonymous. The deadline is Feb 15th. Big thanks to everyone who has taken it so far.

To encourage participants to complete the survey, we're organizing a raffle. Matt and I have five Gluten-Free January T-shirts we're ready to give out for free. These shirts were designed by Matt and they're really cool. I have one myself, and the print and fabric quality are top notch. Here's what the logo looks like:
If you've completed the survey and want to be included in the raffle, please e-mail Matt to let him know you've completed it. Anyone who has already e-mailed Matt to let him know they completed the survey will automatically be entered, so no need for a second e-mail. So far, very few people have written Matt, so your probability of winning a shirt is high!

Gluten-free January Participants: Take the Survey!

Matt Lentzner, Janine Jagger and I have designed a survey for participants of Gluten-free January, using the online application StatCrunch. Janine is an epidemiologist who studies healthcare worker safety at the University of Virginia; she has experience designing surveys for data collection so we're glad to have her on board. The survey will allow us to systematically gather and analyze data on the results of Gluten-free January. It will be 100 percent anonymous-- none of your answers will be connected to your identity in any way.

This survey has the potential to be really informative, but it will only work if you respond! The more people who take the survey, the more informative it will be, even if you didn't avoid gluten for a single day. If not very many people respond, it will be highly susceptible to "selection bias", where perhaps the only people who responded are people who improved the most, skewing the results.

Matt will be sending the survey out to everyone on his mailing list. Please complete it, even if you didn't end up avoiding gluten at all! There's no shame in it. The survey has responses built in for people who didn't avoid gluten. Your survey will still be useful!

We have potential data from over 500 people. After we crunch the numbers, I'll share them on the blog.

Two Wheat Challenge Ideas from Commenters

Some people have remarked that the blinded challenge method I posted is cumbersome.

Reader "Me" suggested:

You can buy wheat gluten in a grocery store. Why not simply have your friend add some wheat gluten to your normal protein shake.

Reader David suggested:

They sell empty gelatin capsules with carob content to opacify them. Why not fill a few capsules with whole wheat flour, and then a whole bunch with rice starch or other placebo. For two weeks take a set of, say, three capsules every day, with the set of wheat capsules in line to be taken on a random day selected by your friend. This would further reduce the chances that you would see through the blind, and it prevent the risk of not being able to choke the "smoothie" down. It would also keep it to wheat and nothing but wheat (except for the placebo starch).

The reason I chose the method in the last post is that it directly tests wheat in a form that a person would be likely to eat: bread. The limitation of the gluten shake method is that it would miss a sensitivity to components in wheat other than gluten. The limitation of the pill method is that raw flour is difficult to digest, so it would be difficult to extrapolate a sensitivity to cooked flour foods. You might be able to get around that by filling the pills with powdered bread crumbs. Those are two alternative ideas to consider if the one I posted seems too involved.

Blinded Wheat Challenge

Self-experimentation can be an effective way to improve one's health*. One of the problems with diet self-experimentation is that it's difficult to know which changes are the direct result of eating a food, and which are the result of preconceived ideas about a food. For example, are you more likely to notice the fact that you're grumpy after drinking milk if you think milk makes people grumpy? Maybe you're grumpy every other day regardless of diet? Placebo effects and conscious/unconscious bias can lead us to erroneous conclusions.

The beauty of the scientific method is that it offers us effective tools to minimize this kind of bias. This is probably its main advantage over more subjective forms of inquiry**. One of the most effective tools in the scientific method's toolbox is a control. This is a measurement that's used to establish a baseline for comparison with the intervention, which is what you're interested in. Without a control measurement, the intervention measurement is typically meaningless. For example, if we give 100 people pills that cure belly button lint, we have to give a different group placebo (sugar) pills. Only the comparison between drug and placebo groups can tell us if the drug worked, because maybe the changing seasons, regular doctor's visits, or having your belly button examined once a week affects the likelihood of lint.

Another tool is called blinding. This is where the patient, and often the doctor and investigators, don't know which pills are placebo and which are drug. This minimizes bias on the part of the patient, and sometimes the doctor and investigators. If the patient knew he were receiving drug rather than placebo, that could influence the outcome. Likewise, investigators who aren't blinded while they're collecting data can unconsciously (or consciously) influence it.

Back to diet. I want to know if I react to wheat. I've been gluten-free for about a month. But if I eat a slice of bread, how can I be sure I'm not experiencing symptoms because I think I should? How about blinding and a non-gluten control?

Procedure for a Blinded Wheat Challenge

1. Find a friend who can help you.

2. Buy a loaf of wheat bread and a loaf of gluten-free bread.

3. Have your friend choose one of the loaves without telling you which he/she chose.

4. Have your friend take 1-3 slices, blend them with water in a blender until smooth. This is to eliminate differences in consistency that could allow you to determine what you're eating. Don't watch your friend do this-- you might recognize the loaf.

5. Pinch your nose and drink the "bread smoothie" (yum!). This is so that you can't identify the bread by taste. Rinse your mouth with water before releasing your nose. Record how you feel in the next few hours and days.

6. Wait a week. This is called a "washout period". Repeat the experiment with the second loaf, attempting to keep everything else about the experiment as similar as possible.

7. Compare how you felt each time. Have your friend "unblind" you by telling you which bread you ate on each day. If you experienced symptoms during the wheat challenge but not the control challenge, you may be sensitive to wheat.

If you want to take this to the next level of scientific rigor, repeat the procedure several times to see if the result is consistent. The larger the effect, the fewer times you need to repeat it to be confident in the result.


* Although it can also be disastrous. People who get into the most trouble are "extreme thinkers" who have a tendency to take an idea too far, e.g., avoid all animal foods, avoid all carbohydrate, avoid all fat, run two marathons a week, etc.

** More subjective forms of inquiry have their own advantages.

Eating Wheat Gluten Causes Symptoms in Some People Who Don't Have Celiac Disease

Irritable bowel syndrome (IBS) is a condition characterized by the frequent occurrence of abdominal pain, diarrhea, constipation, bloating and/or gas. If that sounds like an extremely broad description, that's because it is. The word "syndrome" is medicalese for "we don't know what causes it." IBS seems to be a catch-all for various persistent digestive problems that aren't defined as separate disorders, and it has a very high prevalence: as high as 14 percent of people in the US, although the estimates depend on what diagnostic criteria are used (1). It can be brought on or exacerbated by several different types of stressors, including emotional stress and infection.

Maelán Fontes Villalba at Lund University recently forwarded me an interesting new paper in the American Journal of Gastroenterology (2). Dr. Jessica R. Biesiekierski and colleagues recruited 34 IBS patients who did not have celiac disease, but who felt they had benefited from going gluten-free in their daily lives*. All patients continued on their pre-study gluten-free diet, however, all participants were provided with two slices of gluten-free bread and one gluten-free muffin per day. The investigators added isolated wheat gluten to the bread and muffins of half the study group.

During the six weeks of the intervention, patients receiving the gluten-free food fared considerably better on nearly every symptom of IBS measured. The most striking difference was in tiredness-- the gluten-free group was much less tired on average than the gluten group. Interestingly, they found that a negative reaction to gluten was not necessarily accompanied by the presence of anti-gluten antibodies in the blood, which is a test often used to diagnose gluten sensitivity.

Here's what I take away from this study:

1. Wheat gluten can cause symptoms in susceptible people who do not have celiac disease.
2. A lack of circulating antibodies against gluten does not necessarily indicate a lack of gluten sensitivity.
   
3. People with mysterious digestive problems may want to try avoiding gluten for a while to see if it improves their symptoms**.
4. People with mysterious fatigue may want to try avoiding gluten.
   

A previous study in 1981 showed that feeding volunteers a large dose of gluten every day for 6 weeks caused adverse gastrointestinal effects, including inflammatory changes, in relatives of people with celiac disease, who did not themselves have celiac (3). Together, these two studies are the most solid evidence that gluten can be damaging in people without celiac disease, a topic that has not received much interest in the biomedical research community.

I don't expect everyone to benefit from avoiding gluten. But for those who are really sensitive, it can make a huge difference. Digestive, autoimmune and neurological disorders associate most strongly with gluten sensitivity. Avoiding gluten can be a fruitful thing to try in cases of mysterious chronic illness. We're two-thirds of the way through Gluten-Free January. I've been fastidiously avoiding gluten, as annoying as it's been at times***. Has anyone noticed a change in their health?


* 56% of volunteers carried HLA-DQ2 or DQ8 alleles, which is slightly higher than the general population. Nearly all people with celiac disease carry one of these two alleles. 28% of volunteers were positive for anti-gliadin IgA, which is higher than the general population.

** Some people feel they are reacting to the fructans in wheat, rather than the gluten. If a modest amount of onion causes the same symptoms as eating wheat, then that may be true. If not, then it's probably the gluten.

*** I'm usually about 95% gluten-free anyway. But when I want a real beer, I want one brewed with barley. And when I want Thai food or sushi, I don't worry about a little bit of wheat in the soy sauce. If a friend makes me food with gluten in it, I'll eat it and enjoy it. This month I'm 100% gluten-free though, because I can't in good conscience encourage my blog readership to try it if I'm not doing it myself. At the end of the month, I'm going to do a blinded gluten challenge (with a gluten-free control challenge) to see once and for all if I react to it. Stay tuned for more on that.

A Gluten-free January

Are You Gluten Sensitive?

Many people are totally unaware of the fact that they react poorly to gluten. Because they've been eating wheat, barley and/or rye products every day for virtually their entire lives, they don't know what their bodies feel like without gluten. In susceptible people, eating gluten is linked to a dizzying array of health problems that stem from an immune reaction to gliadins and other proteins in gluten (1). Are you a susceptible person? How do you know?

The gold standard way to detect a gluten sensitivity is to do a gluten "challenge" after a period of avoidance and see how you feel. People who react poorly to gluten may feel better after a period of avoidance. After a gluten challenge, symptoms can range from digestive upset, to skin symptoms, to fatigue or irritability within minutes to days of the gluten challenge.

With 2011 approaching, why not make your new year's resolution to go gluten-free for a month? A man named Matt Lentzner e-mailed me this week to ask if I would help with his (non-commercial) project, "A Gluten-free January". I said I'd be delighted. Although I don't typically eat much gluten, this January I'm going 100% gluten-free. Are you on board? Read on.

A Message from Matt Lentzner

Hi There.

My name is Matt Lentzner. I'm just some guy who lifts weights on his patio and tries to eat healthy. That's not important, but I have an idea that just might be.

I am trying to get as many people as possible to go gluten-free for one month - this January 2011.

I've considered this whole ancestral diet thing and I've come to a conclusion. If you could only do just one thing to improve your health then not eating gluten would be it. This is not to say that avoiding other nasty things like fructose or industrial vegetable oil is not important. They are, but you'd get the most bang for your buck from not eating gluten.

"Eat No Gluten" is simple and easy to remember. I think that sometimes the rules get so complicated and overwhelming and people just give up on it. We're keeping it simple here. Even at this simplified level I see that it's difficult for a lot of folks. I think people, Americans especially, tend not to pay much attention to what they're eating - what it is, where it came from, etc.

Getting people to get out of their eating ruts and think a little about what goes into their mouths is a valuable exercise. It sets the stage for better choices in the future. I hope that some success with the simple step will encourage people to further improve their diets.

I have a website at www.glutenfreejan.com. If you want to sign up just send an email with your first name, last initial, and town of residence to glutenfreejan@gmail.com. If you are on Facebook there's a community you can 'Like' called: Gluten Free January. So far I have over 120 people all over the world signed up. If you are already gluten-free then I still want you to sign up - the more the merrier. You can also use this opportunity to spread the word and sign up your family and friends.

Merry Christmas - Looking forward to a gluten-free New Year.

Matt

The China Study on Wheat

Denise Minger has just put up another great China Study post that's worth reading if you haven't already. Denise has been busy applying her statistics skills to the mountain of data the study collected. She noted in a previous post that wheat intake was strongly associated with coronary heart disease (CHD), the quintessential modern cardiovascular disease. I, and several other people, requested that she work her mathmagic to see if the association could be due to some other factor. For example, wheat is eaten mostly in the Northern regions of China, and CHD rates are generally higher at higher latitudes (vitamin D insufficiency?). This is true in Europe as well, and may be partly responsible for the purported benefits of the Mediterranean diet. You can mathematically determine if the association between wheat and CHD is simply due to the fact that wheat eaters live further North.

To make a long story short, nothing could explain the association except wheat itself, even latitude. Furthermore, she found a strong association between wheat intake and body mass index, typically a predictor of fat mass although we can't say that for sure. That finding echos a previous study in China where wheat eaters were more likely to be overweight than rice eaters (1, 2). Head over to Denise's post for the full story.

The China Study has major limitations built into its basic design, due to the fact that it was observational and pooled the blood samples of many individuals. Therefore, its findings can never prove anything, they can only suggest or be consistent with hypotheses. However, the study also has some unique advantages, such as a diversity of diets and regions, and the fact that people had presumably been eating a similar diet for a long time. I feel that Denise's efforts are really teasing out some useful information from the study that have been de-emphasized by other investigators.

There has been very little serious investigation into the health effects of wheat in the general population. Researchers studying celiac disease and other forms of gluten allergy, and the efforts of the paleolithic diet community in spreading that information (for example, Loren Cordain and Pedro Bastos), have been major contributors to understanding the health effects of wheat. Denise's analysis is one of the strongest pieces of evidence I've come by so far. I think there's enough indirect evidence that investigators should begin taking the idea seriously that wheat, particularly in the form of industrial flour products, may contribute to chronic disease in more than just a small subset of the population.

Real Food XI: Sourdough Buckwheat Crepes

Buckwheat was domesticated in Southeast Asia roughly 6,000 years ago. Due to its unusual tolerance of cool growing conditions, poor soils and high altitudes, it spread throughout the Northern latitudes of Eurasia, becoming the staple crop in many regions. It's used to a lesser extent in countries closer to the equator. It was also a staple in the Northeastern US until it was supplanted by wheat and corn.

Buckwheat isn't a grain: it's a 'pseudograin' that comes from a broad-leaved plant. As such, it's not related to wheat and contains no allergenic gluten. Like quinoa, it has some unusual properties that make it a particularly nutritious food. It's about 16 percent protein by calories, ranking it among the highest protein grains. However, it has an advantage over grains: it contains complete protein, meaning it has a balance of essential amino acids similar to animal foods. Buckwheat is also an exceptional source of magnesium and copper, two important nutrients that may influence the risk of insulin resistance and cardiovascular disease (1, 2).

However, like all seeds (including grains and nuts), buckwheat is rich in phytic acid. Phyic acid complexes with certain minerals, preventing their absorption by the human digestive tract. This is one of the reasons why traditional cultures prepare their grains carefully (3). During soaking, and particularly fermentation of raw batters, an enzyme called phytase goes to work breaking down the phytic acid. Not all seeds are endowed with enough phytase to break down phytic acid in a short period of time. Buckwheat contains a lot of phytase, and consequently fermented buckwheat batters contain very little phytic acid (4, 5). It's also high in astringent tannins, but thorough soaking in a large volume of water removes them.

Buckwheat is fermented in a number of traditional cultures. In Bhutan, it's fermented to make flatbreads and alcoholic drinks (6). In Brittany (Bretagne; Northwestern France), sourdough buckwheat flour pancakes are traditional. Originally a poverty food, it is now considered a delicacy.

The following simple recipe is based on my own experimentation with buckwheat. It isn't traditional as far as I know, however it is based on traditional methods used to produce sourdough flatbreads in a number of cultures. I used the word 'crepe' to describe it, but I typically make something more akin to a savory pancake or uttapam. You can use it to make crepes if you wish, but this recipe is not for traditional French buckwheat crepes.

It's important that the buckwheat be raw and whole for this recipe. Raw buckwheat is light green to light brown (as in the photo above). Kasha is toasted buckwheat, and will not substitute properly. It's also important that the water be dechlorinated and the salt non-iodized, as both will interfere with fermentation.

For a fermentation starter, you can use leftover batter from a previous batch (although it doesn't keep very long), or rice soaking water from this method (7).

Ingredients and Materials

• 2-3 cups raw buckwheat groats
• Dechlorinated water (filtered, boiled, or rested uncovered overnight)
• Non-iodized salt (sea salt, pickling salt or kosher salt), 2/3 tsp per cup of buckwheat
  
• Fermentation starter (optional), 2 tablespoons
  
• Food processor or blender

Recipe

1. Cover buckwheat with a large amount of dechlorinated water and soak for 9-24 hours. Raw buckwheat is astringent due to water-soluble tannins. Soaking in a large volume of water and giving it a stir from time to time will minimize this. The soaking water will also get slimy. This is normal.
   
2. Pour off the soaking water and rinse the buckwheat thoroughly to get rid of the slime and residual tannins.
3. Blend the buckwheat, salt, dechlorinated water and fermentation starter in a food processor or blender. Add enough water so that it reaches the consistency of pancake batter. The smoother you get the batter, the better the final product will be.
4. Ferment for about 12 hours, a bit longer or shorter depending on the temperature and whether or not you used a starter. The batter may rise a little bit as the microorganisms get to work. The smell will mellow out. Refrigerate it after fermentation.
   
5. In a greased or non-stick skillet, cook the batter at whatever thickness and temperature you prefer. I like to cook a thick 'pancake' with the lid on, at very low heat, so that it steams gently.
   

Dig in! Its mild flavor goes with almost anything. Batter will keep for about four days in the fridge.

Thanks to Christaface for the CC licensed photo (Flickr).

Fermented Grain Recipes from Around the World

In my last two posts on grains, I described how traditional food processing methods make grains more nutritious and digestible (1, 2). I promised to briefly describe a few recipes from around the world, then got distracted by other things. Here they are.

Africa: Ogi

Grain fermentation is widespread in Africa and is probably nearly as old as agriculture on the continent. The nutritional importance of fermentation is suggested by the amount of time and effort that many African cultures put into it, when they could save themselves a lot of trouble by simply soaking and cooking their grains.

Ogi is a common West African porridge that's eaten as a staple food by people of all ages. It's even used as a weaning food. It's made in essentially the same manner from corn, sorghum or millet.

Whole grain is soaked in water for one to three days. It's then wet milled, mixed with water and sieved to remove a portion of the bran. Extra bran is fed to animals, while the white, starchy sediment is fermented for two to three days. This is then cooked into a thin or thick porridge and eaten.

South America: Pozol

At first glance, some people may think I left the 'e' off the word 'pozole', a traditional Mexican stew. However, pozol is an entirely different beast, an ancient food almost totally unknown in the US, but which fueled the Mayan empire and remains a staple food in Southeastern Mexico.

To make pozol, first the corn must be 'nixtamalized': whole kernels are boiled in a large volume of water with calcium hydroxide (10% w/v). This is a processing step in most traditional South American corn recipes, as it allows a person to avoid pellagra (niacin deficiency)! The loosened bran is removed from the kernels by hand.

The kernels are then ground into dough, formed into balls and placed into banana leaves to ferment for one to 14 days. Following fermentation, pozol is diluted in water and consumed raw.

Europe: Sourdough Bread

Sourdough bread is Europe's quintessential fermented grain food. Before purified yeast strains came into widespread use in the 20th century, all bread would have been some form of sourdough.

Although in my opinion wheat is problematic for many people, sourdough fermentation renders it more nutritious and better tolerated by those with gluten/wheat sensitivity. In an interesting series of studies, Dr. Marco Gobbetti's group, among others, has shown that fermentation partially degrades gluten, explaining the ability of fermentation to decrease the adverse effects of gluten in those who are sensitive to it (3). They even showed that people with celiac disease can safely eat wheat bread that has been long-fermented with selected bacteria and yeasts under laboratory conditions (4). Rye contains about half the gluten of bread wheat, and is generally nutritionally superior to wheat, so sourdough rye is a better choice in my opinion.

To make sourdough bread, first the dry grains are ground into flour. Next, the flour is sifted through a screen to remove a portion of the bran. The earliest bread eaters probably didn't do this, although there is evidence of the wealthy eating sifted flour in societies as old as ancient Egypt and ancient Rome. I don't know what the optimum amount of bran to include in flour is, but it's not zero. I would be inclined to keep at least half of it, recognizing that the bran is disproportionately rich in nutrients.

Next, a portion of flour is mixed with water and a "sourdough starter", until it has a runny consistency. The starter is a diverse culture of bacteria and yeast that is carefully maintained by the bread maker. This culture acidifies the batter and produces carbon dioxide gas. The mixture is allowed to ferment for 8-12 hours. Finally, flour and salt are added to the batter and formed into dough balls. These are allowed to ferment and rise for a few hours, then baked.

My Experience

I've tried making ogi (millet) and pozol, and I have to admit that neither attempt was successful. Pozol in particular may depend on local populations of bacteria and yeast, as the grains' microorganisms are killed during processing. However, I do eat fermented grains regularly in the form of homemade brown rice 'uthappam' and sourdough buckwheat 'crepes'. The buckwheat crepes are tasty and easy to make. I'll post a recipe at some point.

The first two recipes are from the FAO publication Fermented Cereals: a Global Perspective (5).

The Glycemic Index: A Critical Evaluation

The glycemic index (GI) is a measure of how much an individual food elevates blood sugar when it's eaten. To measure it, investigators feed a person a food that contains a fixed amount of carbohydrate, and measure their blood glucose response over time. Then they determine the area under the glucose curve and compare it to a standard food such as white bread or pure glucose.

Each food must contain the same total amount of carbohydrate, so you might have to eat a big plate of carrots to compare with a slice of bread. You end up with a number that reflects the food's ability to elevate glucose when eaten in isolation. It depends in large part on how quickly the carbohydrate is digested/absorbed, with higher numbers usually resulting from faster absorption.

The GI is a standby of modern nutritional advice. It's easy to believe in because processed foods tend to have a higher glycemic index than minimally processed foods, high blood sugar is bad, and chronically high insulin is bad. Yet many people have criticized the concept.  Why?

Blood sugar responses to a carbohydrate-containing foods vary greatly from person to person. For example, I can eat a medium potato and a big slice of white bread (roughly 60 g carbohydrate) with nothing else and only see a modest spike in my blood sugar. I barely break 100 mg/dL and I'm back at fasting glucose levels within an hour and a half. You can see a graph of this experiment here. That's what happens when you have a well-functioning pancreas and insulin-sensitive tissues. Your body shunts glucose into the tissues almost as rapidly as it enters the bloodstream. Someone with impaired glucose tolerance might have gone up to 170 mg/dL for two and a half hours on the same meal.

The other factor is that foods aren't eaten in isolation. Fat, protein, acidity and other factors slow carbohydrate absorption in the context of a normal meal, to the point where the GI of the individual foods become much less pronounced.

Researchers have conducted a number of controlled trials comparing low-GI diets to high-GI diets. I've done an informal literature review to see what the overall findings are. I'm only interested in long-term studies-- 10 weeks or longer-- and I've excluded studies using subjects with metabolic disorders such as diabetes.  

The question I'm asking with this review is, what are the health effects of a low-glycemic index diet on a healthy normal-weight or overweight person? I found a total of seven studies on PubMed in which investigators varied GI while keeping total carbohydrate about the same, for 10 weeks or longer. I'll present them out of chronological order because they flow better that way.  

One issue with this literature that I want to highlight before we proceed is that most of these studies weren't properly controlled to isolate the effects of GI independent of other factors.  Low GI foods are often whole foods with more fiber, more nutrients, and a higher satiety value per calorie than high GI foods.

Study #1. Investigators put overweight women on a 12-week diet of either high-GI or low-GI foods with an equal amount of total carbohydrate. Both were unrestricted in calories. Body composition and total food intake were the same on both diets. Despite the diet advice aimed at changing GI, the investigators found that both groups' glucose and insulin curves were the same!

Study #2. Investigators divided 129 overweight young adults into four different diet groups for 12 weeks. Diet #1: high GI, high carbohydrate (60%). Diet #2: low GI, high carbohydrate. Diet #3: high GI, high-protein (28%). Diet #4: low GI, high protein. The high-protein diets were also a bit higher in fat. Although the differences were small and mostly not statistically significant, participants on diet #3 improved the most overall in my opinion. They lost the most weight, and had the greatest decrease in fasting insulin and calculated insulin resistance. Diet #2 came out modestly ahead of diet #1 on fat loss and fasting insulin.

Study #3. At 18 months, this is by far the longest trial. Investigators assigned 203 healthy Brazilian women to either a low-GI or high-GI energy-restricted diet. The difference in GI between the two diets was substantial; the high-GI diet was supposed to be double the low-GI diet. This was accomplished by a number of differences between diets, including different types of rice and higher bean consumption in the low-GI group.  Weight loss was a meager 1/3 pound greater in the low-GI group, a difference that was not statistically significant at 18 months. Changes in estimated insulin sensitivity were not statistically significant.

Study #4. The FUNGENUT study. In this 12-week intervention, investigators divided 47 subjects with the metabolic syndrome into two diet groups. One was a high-glycemic, high-wheat group; the other was a low-glycemic, high-rye group. After 12 weeks, there was an improvement in the insulinogenic index (a marker of early insulin secretion in response to carbohydrate) in the rye group but not the wheat group. Glucose tolerance was essentially the same in both groups.

What makes this study unique is they went on to look at changes in gene expression in subcutaneous fat tissue before and after the diets. They found a decrease in the expression of stress and inflammation-related genes in the rye group, and an increase in stress and inflammation genes in the wheat group. They interpreted this as being the result of the different GIs of the two diets.

Further research will have to determine whether the result they observed is due to the glycemic differences of the two diets or something else.

Study #5. Investigators divided 18 subjects with elevated cardiovascular disease risk markers into two diets differing in their GI, for 12 weeks. The low-glycemic group lost 4 kg (statistically significant), while the high-glycemic group lost 1.5 kg (not statistically significant).  In addition, the low-GI group ended up with lower 24-hour blood glucose measurements.  This study was a bit strange because of the fact that the high-GI group started off 14 kg heavier than the low-GI group, and the way the data are reported is difficult to understand.  Perhaps these limitations, along with the study's incongruence with other controlled trails, are what inspired the authors to describe it as a pilot study.

Study #6. 45 overweight females were divided between high-GI and low-GI diets for 10 weeks. The low-GI group lost a small amount more fat than the high-GI group, but the difference wasn't significant. The low-GI group also had a 10% drop in LDL cholesterol.

Study #7. This was the second-longest trial, at 4 months. 34 subjects with impaired glucose tolerance were divided into three diet groups. Diet #1: high-carbohydrate (60%), high-GI. Diet #2: high-carbohydrate, low-GI. Diet #3: "low-carbohydrate" (49%), "high-fat" (monounsaturated from olive and canola oil). The diet #1 group lost the most weight, followed by diet #2, while diet #3 gained weight. The differences were small but statistically significant. The insulin and triglyceride response to a test meal improved in diet group #1 but not #2. The insulin response also improved in group #3. The high-GI group came out looking pretty good. 

[Update 10/2011-- please see this post for a recent example of a 6 month controlled trial including 720 participants that tested the effect of glycemic index modification on body fatness and health markers-- it is consistent with the conclusion below]

Overall, these studies do not support the idea that lowering the glycemic index of carbohydrate foods is useful for weight loss, insulin or glucose control, or anything else besides complicating your life.  I'll keep my finger on the pulse of this research as it expands, but for the time being I don't see the glycemic index per se as a significant way to combat fat gain or metabolic disease.

How to Eat Grains

Our story begins in East Africa in 1935, with two Bantu tribes called the Kikuyu and the Wakamba. Their traditional diets were mostly vegetarian and consisted of sweet potatoes, corn, beans, plantains, millet, sorghum, wild mushrooms and small amounts of dairy, small animals and insects. Their food was agricultural, high in carbohydrate and low in fat.

Dr. Weston Price found them in good health, with well-formed faces and dental arches, and a dental cavity rate of roughly 6% of teeth. Although not as robust or as resistant to tooth decay as their more carnivorous neighbors, the "diseases of civilization" such as cardiovascular disease and obesity were nevertheless rare among them. South African Bantu eating a similar diet have a low prevalence of atherosclerosis, and a measurable but low incidence of death from coronary heart disease, even in old age.

How do we reconcile this with the archaeological data showing a general decline in human health upon the adoption of agriculture? Humans did not evolve to tolerate the toxins, anti-nutrients and large amounts of fiber in grains and legumes. Our digestive system is designed to handle a high-quality omnivorous diet. By high-quality, I mean one that has a high ratio of calories to indigestible material (fiber). Our species is very good at skimming off the highest quality food in nearly any ecological niche. Animals that are accustomed to high-fiber diets, such as cows and gorillas, have much larger, more robust and more fermentative digestive systems.

One factor that reconciles the Bantu data with the archaeological data is that much of the Kikuyu and Wakamba diet came from non-grain sources. Sweet potatoes and plantains are similar to the starchy wild plants our ancestors have been eating for nearly two million years, since the invention of fire (the time frame is debated but I think everyone agrees it's been a long time). Root vegetables and starchy fruit ted to have a higher nutrient bioavailibility than grains and legumes due to their lower content of anti-nutrients.

The second factor that's often overlooked is food preparation techniques. These tribes did not eat their grains and legumes haphazardly! This is a factor that was overlooked by Dr. Price himself, but has been emphasized by Sally Fallon. Healthy grain-based African cultures often soaked, ground and fermented their grains before cooking, creating a porridge that's nutritionally superior to unfermented grains. The bran was removed from corn and millet during processing, if possible. Legumes were always soaked prior to cooking.

These traditional food processing techniques have a very important effect on grains and legumes that brings them closer in line with the "paleolithic" foods our bodies are designed to digest. They reduce or eliminate toxins such as lectins and tannins, greatly reduce anti-nutrients such as phytic acid and protease inhibitors, and improve vitamin content and amino acid profile. Fermentation is particularly effective in this regard. One has to wonder how long it took the first agriculturalists to discover fermentation, and whether poor food preparation techniques or the exclusion of animal foods could account for their poor health.

I recently discovered a paper that illustrates these principles: "Influence of Germination and Fermentation on Bioaccessibility of Zinc and Iron from Food Grains". It's published by Indian researchers who wanted to study the nutritional qualities of traditional fermented foods. One of the foods they studied was idli, a South Indian steamed "muffin" made from rice and beans. 

The amount of minerals your digestive system can extract from a food depends in part on the food's phytic acid content. Phytic acid is a molecule that traps certain minerals (iron, zinc, magnesium, calcium), preventing their absorption. Raw grains and legumes contain a lot of it, meaning you can only absorb a fraction of the minerals present in them.

In this study, soaking had a modest effect on the phytic acid content of the grains and legumes examined. Fermentation, on the other hand, completely broke down the phytic acid in the idli batter, resulting in 71% more bioavailable zinc and 277% more bioavailable iron. It's safe to assume that fermentation also increased the bioavailability of magnesium, calcium and other phytic acid-bound minerals.

Fermenting the idli batter also completely eliminated its tannin content. Tannins are a class of molecules found in many plants that are sometimes toxins and anti-nutrients. In sufficient quantity, they reduce feed efficiency and growth rate in a variety of species.

Lectins are another toxin that's frequently mentioned in the paleolithic diet community. They are blamed for everything from digestive problems to autoimmune disease. One of the things people like to overlook in this community is that traditional processing techniques such as soaking, sprouting, fermentation and cooking, greatly reduce or eliminate lectins from grains and legumes. One notable exception is gluten, which survives all but the longest fermentation and is not broken down by cooking.

Soaking, sprouting, fermenting, grinding and cooking are the techniques by which traditional cultures have been making the most of grain and legume-based diets for thousands of years. We ignore these time-honored traditions at our own peril.

Book Review: Dangerous Grains

Dangerous Grains is about the health hazards of gluten grains. It's co-written by James Braly, an M.D. who specializes in food allergies, and Ron Hoggan, a celiac patient who has written widely on the subject.

Celiac disease is a degeneration of the intestinal lining caused by exposure to gluten. Gluten sensitivity is a broader term that encompasses any of the numerous symptoms that can occur throughout the body when susceptible people eat gluten. The term gluten sensitivity includes celiac disease. Gluten is a protein found in wheat, its close relatives (kamut, spelt, triticale), barley and rye. Wheat is the most concentrated source.

Dangerous Grains is a good overview of the mountain of data on celiac disease and gluten sensitivity that few people outside the field are familiar with. For example, did you know:

• An estimated one percent of the U.S. population suffers from celiac disease.


• Approximately 12 percent of the US population may suffer from gluten sensitivity, according to blood antibody tests.


• Gluten can damage nearly any part of the body, including the brain, the digestive tract, the skin and the pancreas. Sometimes gastrointestinal symptoms are absent.
  


• Both celiac and other forms of gluten sensitivity increase the risk of a large number of diseases, such as type 1 diabetes and cancer, often dramatically.


• The majority of people with gluten sensitivity are not diagnosed.


• Most doctors don't realize how common gluten sensitivity is, so they rarely test for it.
  


• Celiac disease and other symptoms of gluten sensitivity are easily reversed by avoiding gluten.

That's an enormous disease burden coming from a single type of food. I suspect the true incidence may actually be higher, although it's difficult to be sure.

Dangerous Grains also discusses the opioid-like peptides released from gluten during digestion. Opioids are powerful drugs, such as heroin and morphine, that were originally derived from the poppy seed pod. They are strong suppressors of the immune system and quite addictive. There are no data that conclusively prove the opioid-like peptides in gluten cause immune suppression or addiction to wheat, but there are some interesting coincidences and anecdotes. Celiac patients are at an increased risk of cancer, particularly digestive tract cancer, which suggests that the immune system is compromised. Heroin addicts are also at increased risk of cancer. Furthermore, celiac patients often suffer from abnormal food cravings. 

I know several people who have benefited greatly from removing gluten from their diets. Anyone who has digestive problems, from gas to acid reflux, or any other mysterious health problem, owes it to themselves to try a gluten-free diet for a month. Gluten consumption has increased quite a bit in the U.S. in the last 30 years, mostly due to an increase in the consumption of processed wheat snacks. I believe it's partly to blame for our declining health. Wheat has more gluten than any other grain. Avoiding wheat and all its derivatives is a keystone of my health philosophy.

Another notable change that Sally Fallon and others have pointed out is that today's bread isn't made the same way our grandparents made it. Quick-rise yeast allows bread to be fermented for as little as 3 hours, whereas it was formerly fermented for 8 hours or more. This allowed the gluten to be partially broken down by the microorganisms in the dough. Some gluten-sensitive people report that they can eat well-fermented sourdough wheat bread without symptoms. I think these ideas are plausible, but they remain anecdotes to me at this point. Until research shows that gluten-sensitive people can do well eating sourdough wheat bread in the long term, I'll be avoiding it. I have no reason to believe I'm gluten sensitive myself, but through my reading I've been convinced that wheat, at least how we eat it today, is probably not healthy for anyone.

I'm not aware of any truly healthy traditional culture that eats wheat as a staple. As a matter of fact, white wheat flour has left a trail of destruction around the globe wherever it has gone. Polished rice does not have such a destructive effect, so it's not simply the fact that it's a refined carbohydrate. Hundreds, if not thousands of cultures throughout the world have lost their robust good health upon abandoning their traditional foods in favor of white flour and sugar. The medical and anthropological literature are peppered with these stories.

Overall, the book is well written and accessible to a broad audience. I recommend it to anyone who has health problems or who is healthy and wants to stay that way!

Rats on Junk Food

If diet composition causes hyperphagia, we should be able to see it in animals. I just came across a great study from the lab of Dr. Neil Stickland that explored this in rats. They took two groups of pregnant rats and fed them two different diets ad libitum, meaning the rats could eat as much as they wanted. Here's what the diets looked like:

The animals were fed two types of diet throughout the study. They were fed either RM3 rodent chow alone ad libitum (SDS Ltd, Betchworth, Surrey, UK) or with a junk food diet, also known as cafeteria diet, which consisted of eight different types of palatable foods, purchased from a British supermarket. The palatable food included biscuits, marshmallows, cheese, jam doughnuts, chocolate chip muffins, butter flapjacks, potato crisps and caramel/chocolate bars.

It's important to note that the junk food-fed rats had access to rat chow as well. Now here's where it gets interesting. Rats with access to junk food in addition to rat chow ate 56% more calories than the chow-only group! Here's what they had to say about it:

These results clearly show that pregnant rats, given ad libitum access to junk food, exhibited hyperphagia characterised by a marked preference for foods rich in fat, sucrose and salt at the expense of protein-rich foods, when compared with rats that only had access to rodent chow. Although the body mass of dams was comparable among all groups at the start of the experiment, the increased energy intake in the junk food group throughout gestation was accompanied by an increase in body mass at G20 [gestational day 20] with the junk food-fed dams being 13 % heavier than those fed chow alone.

Hmm, this is remarkably reminiscent of what's happening to a certain group of humans in North America right now: give them access to food made mostly of refined grains, sugar, and industrially processed vegetable oil. They will prefer it to healthier food, to the point of overeating. The junk food then drives hyperphagia by interfering with the body's feedback loops that normally keep feeding behaviors and body fat within the optimal range. These data support the hypothesis that metabolic damage is the cause of, not the result of, "super-sized" food portions and other similar cultural phenomena.

The rest of the paper is interesting as well. Pups born to mothers who ate junk food while pregnant and lactating had a greater tendency to eat junk than pups born to mothers who ate rat chow during the same period. This underscores the idea that poor nutrition can set a child up for a lifetime of problems.

Hyperphagia

One of the things I didn't mention in the last post is that Americans are eating more calories than ever before. According to Centers for Disease Control NHANES data, in 2000, men ate about 160 more calories per day, and women ate about 340 more than in 1971. That's a change of 7% and 22%, respectively. The extra calories come almost exclusively from refined grains, with the largest single contribution coming from white wheat flour (correction: the largest single contribution comes from corn sweeteners, followed by white wheat flour).

Some people will see those data and decide the increase in calories is the explanation for the expanding American waistline. I don't think that's incorrect, but I do think it misses the point. The relevant question is "why are we eating more calories now than we were in 1971?"

We weren't exactly starving in 1971. And average energy expenditure, if anything, has actually increased. So why are we eating more? I believe that our increased food intake, or hyperphagia, is the result of metabolic disturbances, rather than the cause of them.

Humans, like all animals, have a sophisticated system of hormones and brain regions whose function is to maintain a proper energy balance. Part of the system's job is to keep fat mass at an appropriate level. With a properly functioning system, feedback loops inhibit hunger once fat mass has reached a certain level, and also increase resting metabolic rate to burn excess calories. If the system is working properly, it's very difficult to gain weight. There have been a number of overfeeding studies in which subjects have consumed huge amounts of excess calories. Some people gain weight, many don't.

The fact that fat mass is hormonally regulated can be easily seen in other mammals. When was the last time you saw a fat squirrel in the springtime? When was the last time you saw a thin squirrel in the fall? These events are regulated by hormones. A squirrel in captivity will put on weight in the fall, even if its daily food intake is not changed.

A key hormone in this process is leptin. Leptin levels are proportional to fat mass, and serve to inhibit hunger and eating behaviors. Under normal conditions, the more fat tissue a person has, the more leptin they will produce, and the less they will eat until the fat mass has reached the body's preferred 'set-point'. The problem is that overweight Westerners are almost invariably leptin-resistant, meaning their body doesn't respond to the signal to stop eating!

Leptin resistance leads to hyperphagia, overweight and the metabolic syndrome (a common cluster of symptoms that implies profound metabolic disturbance). It typically precedes insulin resistance during the downward slide towards metabolic syndrome.

I suspect that wheat, sugar and perhaps other processed foods cause hyperphagia. I believe hyperphagia is at least partially secondary to a disturbed metabolism. There's something about industrial foods that reached a critical mass in the mid-70s. The shift in diet sent us into a tailspin of excessive eating and unprecedented weight gain.