Optimizing Metabolism

by Ingrid Kohlstadt, MD, MPH

Engrained: A Novel Look at Gluten Digestion During Premodern Times

Scientists agree that celiac disease rates are rapidly rising and that these rates are not a mere effect of reclassification or new diagnostic methods. Rather, they reflect that gluten intolerance stands in the epicenter of the exploding rates of chronic diseases.

Great strides are being made in understanding what goes awry with digesting gluten. Among the findings are inconvenient truths that modern agricultural practices and food traditions accelerate digestive disorders. But how big of a factor is modern living, and what might we change in our modern lives to be proactive in reducing digestive disorders? In this Townsend Letter themed on diagnostics, I probe these huge questions in an off-road manner, by going back to a time when salt was the only food preservative, all crops were heirloom, no grains were refined, and chemical manufacturers didn’t define agriculture.

Background

Gluten protein is one of the most difficult proteins to digest, especially when it is in the form of baked bread. Gluten intolerance and celiac disease appear to have occurred here and there among wheat-eating communities for a long time. International travel has long been known to trigger a problem with gluten digestion, and it was called tropical sprue before medical scientists recognized it as the same thing as celiac disease. Yet, at no time in history is celiac disease or poor digestion of gluten known to be common as it is in affluent countries today.

In theory, anything that reduces optimal digestion can contribute to gluten intolerance. The list would include dental problems, infection, inflammation, and emotional stress, and digestion is the rationale by which health professionals may instruct their patients to:

• improve digestion by reducing chronic and acute stress;

• avoid gluten by eating more nutrient-rich seeds, nuts, and spices;

• choose grains that have sprouted, when possible;

• eat more slowly to prevent overeating, especially filling up on bread.

Here the same advice given across modern medical clinics is applied to ancient communities whose well-known narratives are recorded in the Bible. While biblical anthropologists may find modern medicine to be a useful way to study the ancient texts, modern health-care professionals may find the accounts valuable since they reflect a time without the modern causes of digestive disorders.

Taking Away the Bread of Strife and Reinstating the Bread of Life

Chronic conflict is an underlying cause of poor digestion and immune system problems such as gluten intolerance. If there is strife among people who break bread together, this makes gluten harder to digest.

Chronic conflict among brothers and their families recurs in the Bible. The first account ends in murder as Cain kills Abel. Later in the book of Genesis, chronic conflict among siblings again approaches murder. But instead of leaving him for dead, Joseph’s brothers instead sell him off. The conflict was unresolved for decades, as Joseph becomes an Egyptian ruler who organizes grain storage for a famine he anticipates. Not recognizing Joseph as the brother whom they tried to murder, Joseph’s brothers bow to him asking for grain. When they learn of his identity, they are reconciled.

In the New Testament, Jesus tells a parable of reconciliation among brothers. A son leaves home with his share of the inheritance mostly because of his brother’s arrogance. The combination of a spent inheritance and the famine in a distant land drives the estranged brother back home to unexpected reconciliation.

In both accounts, gluten is removed from the diet through famine. The famine forces reunion of estranged brothers and reconciliation takes place. Once chronic conflict is resolved, grain is reintroduced to the diet.

Not Enough Time: The Passover Story

Passover recounts the Israelites flight to freedom, leaving their slavery in Egypt behind. When I was a child, my family would join another family for an annual dinner commemorating this freedom. Because I was the youngest, I got to ask the four questions about what makes Passover different from all other nights. “On all other nights we eat bread with leaven. On this night, why do we eat unleavened bread?” The answer was always the same: not enough time for leavened bread. As a child I was puzzled by this answer, because I had reasoned differently. Bread wouldn’t take longer to prepare than the roasted lamb. Since bread was prepared daily, some yeast dough was presumably ready for baking. But even if it weren’t ready, with a yeast starter bread can rise and be out of the oven in the same time frame needed for the lamb.

I found the answer to my childhood question years later while studying medicine. The Israelites were fleeing in fear that Pharaoh would change his mind again. They were experiencing the fight-or-flight response to the max. The Passover narrative was correct that there was not enough time to eat leavened bread. Even if there was enough time to prepare it as I had reasoned, there was not enough time to digest it.

Unleavened bread would have been easier to digest because it was prepared with less wheat and more barley. Barley has only about a third as much gluten as does wheat. Additionally, leavened bread forms air pockets with the gluten, which reduces its digestibility. In sum, leavened bread would have been digested about as well as rocks.

Manna Avoids Gluten and Promotes a Suitable Microbiome

After their flight from Egypt, the Israelites experienced a dramatically different way of life. They went from being part of a highly advanced civilization to simple nomads. When people groups make demographic shifts, it’s almost always in the opposite direction – from rural to urban.

One reason that it is all but impossible for a people group to transition from urban to nomadic living: the human microbiome. The microbiome is the bacteria and other microorganisms that live in us and on us and hold sway over aspects of our health, especially our immune system and digestion. Nomadic people have manyfold more bacteria than urban dwellers. The microbiome is formed mostly in the first year of life. Adults can change their microbiome somewhat, mostly through diet. So in adulthood it would be unlikely to be able to achieve the optimally large and diverse microbiome.

For the desert-dwelling Israelites to eat foods high in gluten would get in the way of cultivating a healthful microbiome. While they would not have suffered modern-day chronic diseases from eating gluten, this is only because infections and malnutrition would have been more immediate threats to their health.

The background knowledge that modern medicine provides makes the diet of manna, rather than bread, especially intriguing. Manna is described as coriander seed. I take that to mean as coriander seed in taste, aroma, and nutritional properties. However, most scholars assume that the comparison is one of appearance. Yet that doesn’t match, because coriander seed is light brown, spherical, and the size of peppercorns. Manna is said to look like white resin flakes, which don’t look at all like coriander seeds. I therefore reason that coriander seed is the food which most closely matched manna.

Coriander does not contain gluten, nor is it a grain. Most interestingly, it is the seed of the widely cultivated cilantro plant now renowned as a super food because it cultivates a very healthful microbiome. It was also free of mold spores and leaven to further support a healthful microbiome.

Rituals That Made Grain Easier to Digest: Pilgrim Feasts of the Ancient Hebrews

When grain is cut and left in the field it undergoes changes significant for human digestion. Natural enzymes break down the plant’s proteins such as gluten.

The ancient Hebrew people observed the first barley harvest (feast of First Fruits) and the first wheat harvest (Shavuot) as pilgrim holidays. The newly harvested grain was eaten only after the men returned from the temple. In order to observe these rituals, both the barley and wheat were cut and laid in the fields for approximately a week. As the grain sat during those warm spring days, it became easier for the people to digest it.

Nutrients Chaperone Gluten: The Practice of the Shemitah

As grain grows, it takes in nutrients and microbes from the soil. These same nutrients and microbes promote human digestion of the gluten-containing grains. The nutrients and microbes become less plentiful in the soil as the land is repeatedly farmed.

When the Israelites lived in Egypt, they ate grain grown on the banks of the Nile. Water hauled from the Nile was a pipeline of rich nutrients and microbes. And each rainy season, the Nile flooded and made the soil black with nutrients.

But where the ancient Hebrew people settled, there was no Nile nutrient pipeline for their crops. They approached the challenge of nutrient- and microbe-rich food differently. They were the first to use a crop rotation that left the land was to be fallow every seventh year. During this year, called shemitah, wild plants and cover crops would grow and give the soil different nutrients. Livestock would graze freely on the land, further enriching the soil with minerals and microbes. In this way, shemitah played an important role in safe digestion of gluten, by promoting the presence of the antioxidant nutrients that chaperone gluten through the gastrointestinal tract.

Mindful Eating: The Blessing over the Bread

“Slow down and chew your food.” Medical science calls this common advice mindful eating. It helps us smell and taste our food more fully, so that the brain has the time that it needs to signal when we’ve eaten enough. In other words, we are less likely to overeat when we slow down and use our senses. With mindful eating, our food is better digested to get the tiny nutrients out of it, not just the calories. It also reduces the chance of developing food allergies at a later time. Mindful eating is so important that some dieters use an invention called the HAPIfork. An electronic sensor inside the fork causes it to vibrate if you eat too fast.

But long before the HAPIfork, people of faith have said a blessing over their bread. A blessing is a form of mindful eating.

Application

Ongoing research into the causes and treatments of gluten disorders form an anthropologist’s toolbox. Here the tools have been applied to a well-known ancient text, which suggests that digesting gluten might possibly be a longstanding health challenge. Prevention may have benefited communities long before the added risks imposed by modern agriculture. As health-care practitioners, we can apply the anthropologic tools to helping our patients overcome digestive diseases, despite the added challenges imposed by modern living.

Ingrid Kohlstadt, MD, MPH, FACPM, FACN

Faculty Associate, Johns Hopkins Bloomberg School of Public Health

Executive Director, NutriBee National Nutrition Competition Inc.

Editor, Advancing Medicine with Food and Nutrients (CRC Press; 2013)