In defense of nutrients

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WARNING: Embedded in this article is an allusion to a disturbing mental image that may be difficult to expunge from the mind. Anyone of a sensitive nature may wish to skip this post altogether.

Irony of irony. As a food scientist, I have become compelled to defend nutrients while the nutritionist on this site appears to be more concerned about food! Two weeks ago, I took on the concept of nutritionism as proposed by Gyorgy Scrinis and popularized by Michael Pollan. I suggested that if the concept of nutritionism is true, then everything we know about nutrition is wrong. Last week, a nutritionist who agreed to write a guest blog, indicated that the face of nutrition is changing and we need to wait for the smoke to clear to see if we are in the middle of a paradigm shift. The question I ask and attempt to answer today is

Do nutrients matter?

My response is a strong YES, they do matter. Scrinis downplays their importance in the grand scheme of things, and Boyar seems to agree. The reason nutrients matter is that while in our mouth and subsequently through the digestive tract food is being broken down into its chemical components. To get food into our mouths and thus our stomachs, food must be appealing enough to be consumed. Once that food leaves the mouth, however, the body mines the converted food for its nutrients. We are now being told that the nutrients in processed food don’t count.

Visualize in your mind a puddle of fresh vomit. It was recently in the stomach and was expelled from a body for any one of a number of reasons. Some parts of the contents may resemble food materials, but most do not. Rather the gemisch likely resembles a foul-smelling pinkish or brownish smoothie with clumps of unidentifiable substances. If the stomach had eyes, it would probably not recognize what foods were represented in the materials moving down the esophagus. The stomach does not have eyes. What it does have is an array of chemicals such as acids, enzymes and hormones which interact with the materials present that were formerly components of foods. From the time food leaves the mouth, the body acts on these materials through a complex series of chemical reactions. In a very real sense we are all chemically dependent. We depend on breathing for oxygen from the air. We depend on food and beverages for water, energy, vitamins, minerals and other nutritionally related compounds.

Thus, we eat food, but the body processes meals into a source of nutrients! I sincerely doubt that the stomach can tell whether a substance in its confines is natural or synthetic or whether it is organic or not. Its highly acidic environment starts breaking apart large molecules to form smaller ones and separating water-soluble components from those that are not. Hormones come in to help harvest the usable chemicals. Digestion focuses its attention on what compounds are present and how to deliver them to the small intestine. Absorption of these components mostly happens after the bulk of the material, generally referred to by nutritionists as chyme, leaves the stomach. Small molecules such as simple sugars, alcohol and MSG can be absorbed into the bloodstream from the stomach, particularly if consumed without solid food. Fat, dietary fiber, and to a lesser extent protein, can slow stomach emptying time and thus provide a more even level of absorption.

The real action starts once the chyme reaches the small intestine as proteins are broken down to amino acids, fats into fatty acids and carbohydrates to simple sugars. Our resident microbes are active participants in the process. It is here that these small molecules along with vitamins and minerals can cross the linings of the gut and into the bloodstream with the help of a chemically assisted transport system. Toxins can also cross over the intestinal barrier in a similar fashion. By this time all association with the original food items is completely gone. Some compounds are more readily absorbed than others due to slight variations in chemical structure or the presence of other compounds present. This property is known as bioavailability.  Molecules that bind nutrients to decrease bioavailability can be present in processed products or occur naturally in whole foods. Once again, it is chemistry that is important and not whether the original food was formulated, organic, processed or whole.

It is not just the chemicals that cross the barrier that are important, but those chemical components present that contribute to a healthy microbiome. It is becoming clear that the microbes in our gut are important to our health. The difference between a healthy gut and an unhealthy one is becoming clearer, but it is not fully understood what foods distinguish between varying degrees of gut health. Processed food becomes an easy scapegoat, but, as with many food issues, life is more complicated than simple sayings.

Once the nutrients have been mined in the small intestine, the remaining chemical components that could not cross the intestinal barrier collect in the large intestine. Included in these remaining chemicals are the complex carbohydrates known as dietary fiber that can help propel the remaining non-digestible materials and numerous microbes out of the body. Although most of us have little interest in human waste, forensic microbiologists can learn much about the composition of our microflora and like-minded nutritionists can learn about what we were and were not able to digest.

There are many recommended diets to promote health. The ideal diet is one that provides a balance of essential nutrients without contributing to excess weight. Too many fad diets achieve their objectives by restricting specific foods or types of foods. As a result, they may lead to nutritional imbalances. Some of these diets recommend a vitamin and mineral supplement just to be on the safe side. Diets that require chemical supplementation are NOT balanced diets. The Angry Chef suggests that most of the testimonials for personal diets found on the internet represent a regression towards the mean. Upon switching to the newly recommended diet, the health of the advocate has improved from a previous condition. Short-term benefits are highlighted, but the true benefits and limitations of a specific diet take a long time to become apparent. Most of us are too impatient to stick to a diet to discover its true consequences, which is one reason why most weight-loss diets fail.

Bottom line: The point of this whole exercise is, of course, that once food leaves the mouth, food ceases to be enticing fare and devolves to a rather unpleasant mix of chemicals that are mined for its nutrients.Yes, nutrients do matter. They matter whether they come from whole foods such as fruits, vegetables and meats or come from processed or formulated foods. Once a food leaves the mouth, the value of nutrients to the body is dependent on their chemical properties and not their cultural-traditional heritage as Scrinis suggests. We eat food for nutritional, personal, social and other benefits. When it comes to nutrition, however, it is the nutrients we mine in the context of total calories that we consume that helps determine long-term health.

Next week: Everything else is just chemical

 

 

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