– OPINION –
These days, there are so many nutritional studies being regurgitated to the public by the media that it’s just too much to swallow. And that’s a good thing, because they’re junk food for your brain.
There is a very big problem with nutritional research that makes it unreliable. It involves several variables that are ignored in virtually every study unless these issues are specifically looked at, which is rare.
The first issue is about studies that assess the nutritional value of food. These studies analyze the composition of foods by breaking them down in the laboratory and measuring the amounts of food components, such as how much fat, protein, carbohydrates and various vitamins and minerals it contains.
It goes without saying that this type of analysis must take into account whether the food is cooked or raw. Cooking can inactivate certain vitamins and other heat-sensitive nutrients, as well as some phytotoxins found in many plant foods, especially beans. Cooking also helps break down some complex carbohydrates and proteins.
Of course, cooking is actually a chemical reaction process, and temperature matters. There are several products made by heating food to cooking at 212 degrees F, versus frying or baking at 350 degrees F.
For example, cooking carbohydrates above 248 degrees F causes the production of acrylamide, a nerve toxin and carcinogen. These cooking products are not included in most nutritional research, despite their impact on health. See Boiled to Death.
Nutritional studies of food components typically consider whether the food is cooked or raw, although they ignore the cooking products added to the food.
What is usually not considered is what happens to the food once it leaves the plate or bowl and enters your mouth. How much of the nutrients in food are processed and absorbed by your body after it passes your lips is anyone’s guess.
Digestion involves the further breakdown of food, and it starts with chewing. If you don’t chew your food thoroughly, and instead swallow it in pieces, you minimize the food’s exposure to all the downstream digestive enzymes that help you further digest it. Chewing is important not only to prevent choking, which is a real problem, especially for people who don’t have all their teeth or who take too large a bite. So you really need to start your food’s journey through the digestive tract by chewing it thoroughly.
Prolonged chewing also adds a lot of saliva to the food, which is the first exposure your food gets to a digestive enzyme. The enzyme is called ptyalin and attacks carbohydrates, converting starches into shorter-chain sugars. However, this enzyme needs an alkaline environment to work, and saliva is alkaline, so it works in your mouth. But once the chewed carbohydrates enter the stomach, the environment becomes acidic, and this inactivates the ptyalin. So the longer the food sits in your mouth, the more effectively you can break down carbohydrates before they reach the stomach.
Once in the stomach, carbohydrates must wait until proteins are first exposed to enzymatic digestion with the enzyme pepsin. Stomach acid is necessary for the activation of pepsin, which acts on these proteins. Meanwhile, the carbohydrates and fats in the food are stirring along with the proteins in the stomach, waiting for things to be broken down enough to move out of the stomach and into the small intestine. (Large chunks of food need to stay in your stomach long enough to become small enough to pass through the sphincter that separates the stomach from the intestines, which is another good reason to chew your food thoroughly.)
In the intestines, stomach acid is neutralized by bile from the gallbladder, lowering the acidity so that other enzymes from the pancreas can work on the carbohydrates, fats and proteins. This digestion continues, but it obviously depends on how quickly the food travels through the intestines, how well the food is mixed with the digestive enzymes, and how much enzyme your pancreas secretes into the intestines. It is affected by how healthy your liver and gallbladder are (the liver makes the bile that is stored in the gallbladder) and how healthy your pancreas is.
Further down the intestines, the resulting digested nutrients can finally be absorbed. This process also depends on the health of the intestinal wall and the blood supply to the intestines. That’s why you should rest after eating. The digestion process is hindered if you are physically active and transport blood from the intestines to the muscles.
This is also why fast food is actually slow to digest. Food eaten during flight enters a digestive system that is on hold. If you are stressed while eating, your stress hormones slow down digestion. And this can cause digestive problems, including gas.
And this raises the other problem that nutrition research ignores. The gas is produced by bacteria and yeasts that live in the intestines. They are your constant dinner guests and they get the first bite of your food.
What you absorb from your intestines are actually the products of the microbial fermentation and digestion of that food. Your body helps break down food into sugars, amino acids and fatty acids, and these are food for the microbes that house your guts.
As a result, we end up absorbing the chemicals of bacterial and yeast fermentation and digestion. These are not taken into account in the nutritional assessments of the food. For example, potatoes do not contain alcohol, but when you eat potatoes, the sugars are converted into alcohol through microbial fermentation, which is reflected in blood alcohol levels.
So you only really know what you are eating when you consider what your bacteria and yeasts are serving you. We absorb these products and must metabolize them and remove them from our bodies.
In fact, most of these bacterial products are volatile and can be smelled on the breath. And amazingly, most of the metabolites in your blood come from gut microorganisms.
Researchers have used breath analysis to study these and understand the impact of gut bacteria on our overall health.
Nutritional research into food nutrient availability ignores this microbial aspect of our digestion. This increases uncertainty about the nutritional value and impact of food.
Admittedly, it would be difficult to study this microbial variable because it depends on the types of bacteria and yeast in your body, which can change over time. But the microbial digestion of our food means that what we ultimately get from our meal is anyone’s guess.
As you can see, digestion is not the same between people, or even for the same person at different times. Each of the steps of digestion introduces inefficiencies in the process that affect the amount of nutrients in the food you absorb. Add to that the products of microbial digestion, and you understand that nutritional information is a guess at best.
Of course, we can further disrupt digestion with some medications, especially proton pump inhibitors or PPIs. These medications are given to people who suffer from excessive stomach acid and reduce the stomach’s ability to produce acid. A major problem here is that stomach acid is important. It serves to help activate pepsin to digest proteins, but it also helps kill bacteria in the food. The stomach acidity is high and most bacteria do not like that. So acid helps to control bacteria that enter your body through food.
And there is more. Please note that the bacteria in the intestines also need to be managed. Stomach acid prevents these insects from entering the stomach and passing through your esophagus to your throat. From there, these bacteria can enter the lungs and paranasal sinuses and cause real problems. These are the consequences of a disease called Small Intestine Bacterial Overgrowth, or SIBO, and is a common side effect of PPI use.
You can see why there is increasing awareness of the role of gut bacteria in human health and disease. We live with bacteria and they affect us. The digestive process nourishes us and them. And what we get from our food depends on which species of bacteria came along to eat it.
You can now also see that performing a laboratory analysis of a food product will not tell you what it really offers you in terms of nutrition, or in terms of microbial metabolic waste management. Reality is much more complex than a test tube. And that is why nutritional research is generally unreliable.
If you’re tired of bad research and its confusing results, stop listening to the “experts” and start listening to your body. Your bacteria will also have a say. Ultimately, you’ll have to experiment with foods to see which foods make you feel the best. But keep in mind that your food preferences may change as your microbial guest list changes. And after taking antibiotics, all bets are off.
This can all be hard to swallow, so chew on this information for a while and think about it until your mind completely digests it. Enjoy your meal.
References:
The breath volatile metabolome reveals the impact of dietary fiber on the gut microbiota: proof of concept in healthy volunteers https://www.thelancet.com/journals/ebiom/article/PIIS2352-3964(22)00232-8/fulltext
From poisoned pastries to poisonous toast: how to remove nerve toxins from your food
https://theculturedoctor.substack.com/p/from-poisoned-pastry-to-toxic-toast
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