Greger on Beets, Nitrates, and Athletic Performance
Never one to shy away from talking about the benefits of greens, Dr. Michael Greger has a very interesting blog post, Using Greens to Improve Athletic Performance, that highlights his series of videos on nitrates, nitrites, and nitric oxide which are now available on NutritionFacts.org.
To sum it up, beets and many dark leafy greens contain nitrates which can improve athletic performance, by making oxygen usage more efficient, via the body turning the nitrates into nitrites and then into nitric oxide.
But if nitrites from plant foods can be beneficial, what about the nitrites added to cured meat which are supposed to be so harmful? It turns out that in the presence of vitamin C, nitrites from plants are converted to nitric oxide, while the nitrites in meat tend to be turned into nitrosamines which are, in turn, thought to be the culprit in cured meats.
March 25th, 2012 at 11:05 pm
Thanks, this was valuable information. Those who are interested in knowing more in nitrates (an their benefits) may want to check my take on the subject. I also cover the effect of hot houses and agricultural processes on the nitrate levels.
http://www.pronutritionist.net/en/nitrates-are-beneficial-where-did-i-get-it-wrong/
March 26th, 2012 at 8:29 am
Reijo,
That’s a very interesting article. My impression from it is that you consider trying to increase nitrate intake as potentially having some dangerous side effects. Is that right? I was also surprised to read that organic vegetables would not provide nitrates – am I reading that right? I also don’t understand the part of your title that says “Where did I get it wrong?”
March 27th, 2012 at 12:07 am
My English is far from perfect 🙂 We were thought in school (during dietitian studies 1990s) that both nitrates and nitrites are bad for health. There is no health benefits associated with them, was the story. One should limit spinach and beet root intake. That’s were the title came from. This is European perspective.
Yes, nitrates have been associated to some forms of cancer. However, that association is quite weak and not broadly accepted. Another thing, nitrates are linked (weakly again) to infant methemoglobinemia. This are basically the two risks I wanted to be acknowledged.
I guess that’s something similar to what professor Martin Katan also wanted state in his editorial in AJCN 2009 ( http://www.ajcn.org/content/90/1/11.full ).
March 27th, 2012 at 8:01 am
Reijo,
Thanks for your reply. Do you have a study that shows that nitrates are minimized in organic foods?
March 28th, 2012 at 2:24 am
At least this US based report show this:
http://www.agroecology.org/documents/Joji/leafnitrate.pdf
It was also stated in the Katan editorial (above) and ESFA report as well.
March 28th, 2012 at 12:58 pm
Reijo,
If you look at Table 2.6, 2.7, 3.2, and 3.6, it appears to me except for a few instances, the organic romaine and iceberg lettuces had about as much nitrate as the conventional. The organic spinach had about 25% or more of the conventional. Am I missing something?