There is a massive amount of conflicting research/information on nutrition out there. Eggs are great for us, eggs are clogging our arteries, eating carbs is good and gives us energy, carbs make us lethargic and fat. As someone who, after years of treating their body like crap, wants to make an effort and eat things that are good for me, it seems impossible because at this point I feel like whatever arbitrary statement about food you take (like, eating 1/2 green apple increases your metabolism but only on Tuesdays and Fridays), you will find some type of research “confirming” it. Why is it so hard to have concrete research/evidence of what is good for our bodies and what isn’t, at least generally? Isn’t it science? How are we supposed to know what to eat??
In: Biology
The effects of nutrition are hard to study for a lot of reasons. One big one is that the effects of a diet aren’t always obvious in the short term. You might be eating something now that’s bad for you, but if it takes 30 years of eating for problems to manifest you’re not gonna know for a while. That’s why it took people so long to agree that smoking was bad: One cigarette won’t hurt you much, but doing it for years will.
You cannot easily study the longer term effects of a particular diet on humans. You cannot control what people eat for years on end, and you cannot trust that they accurately report on what they’ve eaten for the last several years.
Also, human body by itself is: 1. insanely complex and complicated 2. varied from person to person, dependent on climate the person lives in, varied between sexes, between races, genetics and basically due to anything that affects you in any long-term way
And than, science is all about control experiments where you change a single variable at a time. That just can’t happen with human nutrition.
Hard science, e.g. physics, chemistry, etc.. build rigorously on basic, well established, mechanisms of nature. In general, with hard science, when you claim something, you find a correlation, come up with a theory of a mechanism on how you think that correlation comes about and then come up with a way of testing the mechanism by controlling all other factors and seeing if your mechanism really works the way you thought it did.
Bio-chemistry would be the ‘rigorous’ hard science that should be behind nutrition and medicine. Unfortunately there is a huge gap between where bio-chemistry ends and where nutrition start. In some cases, proper bio-chemical mechanisms can be shown. More often though, nutrition come up with claims purely based on correlations from observational studies, where the underlying bio-chemistry is not understood at all.
Due to factors like these, the research studies coming out in nutrition have a huge signal-to-noise ratio problem to the point where you can pretty much find them to support any personal pet theory, well accepted by the field or not.
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