Do people really follow his health advice?
I think there’s an Artscroll translation of the Kitzur which curiously, translates everything but the Kitzur’s health advice (much of which seems to be from the Rambam). I’d say that’s a subtle message that many people think such advice shouldn’t be taken seriously. I think it should be taken seriously, but it’s not the last word.
One thing I remember from the Kitzur is that it says whole wheat bread is healthier. Now we know that to be true. But it also says carob is always unhealthy, which I think there’s no scientific basis for.
Can anyone summarize the main points of Rambam’s health advice?
Here are some things I think he advises (with my comments):
1) eat only until you’re 3/4th full (probably good advice — eating until you’re completely full or overfull causes fatigue and, probably, obesity)
2) don’t eat until you’re hungry and until after you’ve done some exercise (probably good advice, with the caveat that one should eat a decent-sized meal early in the day)
3) one shouldn’t walk around or exert oneself after eating (I don’t think this is true for walking — there’s nothing wrong with walking after eating)
4) sit still or lean to the left while eating (I think there’s no scientific basis for leaning a certain way)
5) sleep eight hours a night (good advice — most people need 7-8 hours a sleep, according to recent research)
6) sleeping on one’s right side early in the night and left side later in the night (this might be codified as halacha, but I’m not sure if people follow it, and I doubt there’s a scientific basis for it)
7) his statements in favor of regular strenuous exercise (definitely good advice)
8) foods should be eaten in a certain order (meat from a small animal before a big one, certain fruits before a meal but others after a meal, etc.) (not sure about this one; some of it might be valid)