To 'Elite or Bust!'
true dat, vD is formed when cholesterol in your skin is exposed to UV radiation, isomerizes, then gets double hydroxylation in liver and kidneys. but depending on season and latitude, some people may go without getting much sunlight for months. true what you get in the summer probably does ok for you through the winter, but evidence suggests the old DRI's or AI's or DV's or whatever you want to call the recommended amount of intake is something like 3x too low. also vD's role as a nuclear-acting steroid hormone (it's more accurately classified as a hormone not a vitamin) may be inhibited by some components of cereal grains such as wheat germ agglutinin.
iron in green leaves like spinach isn't as absorbable as meat iron cause greens iron is non-heme iron and meat iron is heme iron. oxidation state of iron also matters. for non-heme iron, the reduced form Fe2+ is more absorbable than Fe3+...so if you're gonna get all your iron from greens (or grains) best do so with a lemon juice dressing or a cup of OJ.
for the nerds:
http://www.ncbi.nlm.nih.gov/pubmed/2507689
can't really compare us to cows...ruminants have quite different digestive processes than we do.
the calcium in plants tends to inhibit the iron absorption in plants. that's why if you're a meat person you don't drink milk with your steak.
for the nerds:
http://www.ajcn.org/cgi/reprint/68/1/3.pdf
(this one is pretty readable--bottom line is calcium seems to inhibit absorption of heme and non-heme iron)
i'm not familiar with the new research on B12 in organic produce...any links for me? as far as i know any B12 in produce is next to nothing compared to the amounts in meat.
interesting that the microflora in our large intestines make B12, but we can't absorb it cause we absorb B12 in the small guts.
no plants have DHA which is important for brainnnns. and despite the fact that ALA from stuff like flaxseed technically converts to DHA, less than 2% of ALA makes it to DHA because humans have reduced activities of the desaturase and elongase enzymes necessary for these conversions, so flaxseed is essentially useless in that regard. best eat some salmon...i think the plant exceptions are one or two kinds of algae or liverworts or something like that. lots tastier to eat fish though.
agreed about the meat and dairy lobbyists. the kind of meat i'm advocating is LEAN, not feed lot type stuff.
also, from the paleo perspective, our ancestors simply did NOT eat grains (agricultural revolution only happened 10,000 years ago...modern humans have existed for about 195,000 years). and it was impossible to get enough calories from veggies, fruits, and nuts, thus there is good evidence that paleolithic diets consisted of about 55% calories from meat and fish and 45% calories from plants...latitude dependent with regard to fish vs. plants as many plants aren't available in northern latitudes when everything's frozen.
so from an evolutionary perspective vegetarianism makes no sense at all. but from a practical standpoint, in today's society, eating paleo is impractical and expensive...but from a scientific standpoint its on the $$
and your case study for your own PR's doesn't count. i have been massively boozing and recently ran a marathon time waaaay better than anything i've run in other distances (2:28 marathon, pr's 15:55 5k, 26:10 8k) but that doesn't mean that its cause my boozing i ran a decent marathon, as much as i'd like to think so. :)
in response to the other guy posting about how supplements aren't as well absorbed as the natural forms, i think in general that's true but i think fish oil capsules are an exception. not 100% sure on that.
rebuttals...