How do you suppose that 'eat like a sane person' (as though that were precise advice) gives exactly optimal nutrition, with no gains to be had from any increase or decrease of anything? It seems vanishingly improbable that there is no substance that a human could benefit from getting slightly more or less of in the diet.
It does not seem vanishingly improbable to me. Any organism that must eat complex foodstuffs (which includes all animals big enough to see) must deal with the fact that they have no way to obtain precisely the right quantity and proportions of everything that they need. Their bodies therefore need to be robust to wide variations in their dietary content, resulting in a plateau, possibly a very wide one, between deficits and excesses that do measurable harm. If this is so, then there is no such thing as the exactly optimal amount of a nutrient. Instead, there is a broad range, and if you manage to hit that barn door it doesn't matter where.
I think that what you say has to be true at the population level. (The panda provides an obvious counter example, but since the panda is going extinct, that is merely a nit pick. Successful species, such as rats or humans are robust to wide variations in their dietary content.
However, at the micro-level, the truth of this proposition is maintained by ruthless culling. The rat population is riddled with weaklings, who lose out in life due to diet-induced health problems.
As for the human population, we have a different perspective on these matters. I can st...
(Original Post: Announcing the Quantified Health Prize)
I've recently been hired by Personalized Medicine, a new research company trying to bring Less Wrongian rationality to the medical world. We're giving away a $5000 prize for well-researched, well-reasoned presentations that answer the following question: What are the best recommendations for what quantities adults (ages 20-60) should take the important dietary minerals in, and what are the costs and benefits of various amounts?
Entries are now due by January 15th, 2012. This is an update from the original date of December 31st, 2011. However, we will not change this deadline again, and it will be strictly enforced. If you submit your entry on January 16 at 12:01 AM Pacific time, we will not read it.
Why enter the contest? If you have an excellent entry, even if you don’t win the grand prize, you can still win one of four additional cash prizes, you’ll be under consideration for a job as a researcher with our company Personalized Medicine, and you’ll get a leg up in the larger contest we plan to run after this one. You also get to help people get better nutrition and stay healthier.
More info about the contest, and instructions for submitting entries, can be found at the contest website at http://www.medicineispersonal.com/contest/home. Good luck!