An Unrecognised Paradox.
Nutrients and toxins, and what defines, divides and unite these semantic opposites in biology
There are two basic premisses that unites all schools of dietetics, how diet relates to disease and that is the concept of nutrient deficiency and nutrient toxicity. Because we need nutrients to survive and function properly, the first premise can be considered self-evident, a true axiom, and we’ll get to the specifics later in the coming sections of this chapter. However, the idea of nutrient-toxicity, that nutrients when eaten in excess behave like a poison in the body seems to be self-contradictory, since the definition of a nutrient is a substance that organisms need in order to live and grow while a poison is defined as a substance that can kill organisms or make them ill.1)https://dictionary.cambridge.org/dictionary/english/nutrient2)https://dictionary.cambridge.org/dictionary/english/poison In logical deduction this simple semantic contradiction is usually dismissed by applying a principle of toxicology that states that “it is the dose that makes the poison”, that getting to much of something good can make it bad. This seems to explain away the inherent contradiction in considering that nutrients can be synonymous with poison when they are in fact opposites by definition. The practical utility of this toxicology-principle is undeniable, however, like all other principles it is only true in a practical sense and is not meant to be taken literally and can definitely not be said to be a theoretical axiom. Temporarily disregarding the value of theoretical truth, what organisms fundamentally care about are to function in the world, hence the why and how of a principle is not important as long as the outcome can be somewhat reliably predicted by acting in accordance with it. In the case of the toxicology-principle, people who overeat tend to get metabolic issues and when they eat less they seam to get healthier. To find the answer as to why and how this seams to be the case is therefore often portrayed as bing of trivial importance, and a matter of intellectual curiosity rather than a practical necessity and it is often stated that if we just acted on this principle things would sufficiently improve. The problem is that we currently don’t, and even when we do our health don’t seam to improve sufficiently (and sometimes it even gets worse), and if a principle, no matter how well it worked in the past, stops being of practical use, it is time to re-examine it, bring it closer to theoretical truth, and then act accordingly. So, do nutrients really poison us when eaten in excess, or is there more to the story?
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