Should we be eating a handful of greens 6x a day for optimal health?
If I had to sum it up, here are the main points that are in some of the above links.....
1) Dr Esselstyn has no evidence for *his* recommendation of eating certain nitrate rich veggies and it only makes adherence harder. Over the years I have consulted/coached many of his patients and the adherence to this recommendation is always an issue. To try and maintain the recommendation, some of these patients have resorted to nitrate and/or beet supplements, beet juice and eventually giving up because they can’t do it “right.” There are some of the WFPB doctors who will even "help" by offering them supplements.
Remember, his first study was on about 25 people and they were put on the original Ornish diet, which included non fat dairy. There was no recommendation to consume any specific amount of greens in their diet in the 12 years of published follow-up. There was also no recommendation for any specific amount of greens in the diet in his later study of 197 case series nor was there any dietary analysis of the subjects. And there is no specific recommendation for a specific amount of greens in any other of the studies on heart disease reversal including the original Ornish RCT study, the Pritikin studies, the McDougall studies, the Gould studies, the CHIP/7th Day Adventist studies, or any other. So, not only was this not part of the diet in the published studies, there is also no study shadowing a benefit to the new recommendations over the older ones.
2) There is a study Dr Esselstyn quotes on Okinawa women to prove his point. Here is a link to my review of it.
https://www.drmcdougallforums.com/viewt ... 13#p377385It was in women who were eating less then 1/2 the minimum recommended amount of any vegetables. As the intervention, half of them were given vegetables each week to help them reach the minimum. Yes, this made a difference and while some of the veggies were greens, some where not. So basically, in this study, just hitting the minimum amount of recommended veggies (greens or not), from a very low intake made a difference. Those following our recommendation are way over the recommended amounts especially if they are following MWL and starting their meals with a veggie soup and/or salad, and making their plate up to 50% no starchy vegetable.
3) The impact of food (including greens), beet root juice and supplements has been well studied, not only in the health community but also in the exercise community as athletes are always willing to do anything to give them an advantage. Many of these studies are very well done and we can learn much from them. A friend of mine, an RD and Exercise physiologist, did some of the studies.
4) In the testing on athletes on the impact of nitrates on health markers such as blood pressure, flow mediated dilation, exercise time, etc, here is what they have found..... Taking the equivalent of about 400-500 mg of nitrates from either food, juice or supplements, which is about a 14 oz can of sliced beets or 4 oz of Beet Juice, produced a significant effect. However, that effect doesn't even peak till 3-4 hours later, then stays elevated for at least 6-8 hours and doesn’t return to baseline till 12, sometimes 24 hours. More wasn’t better. Even just taking it 3x a week had a significant benefit. Here is a chart from one of the studies. These results are fairly consistent. (One chart is Nitrate and one is Nitrite).
The companies that sell these nitrate and beet products recommend no more then one dose a day, and at most 2 (for a short period). Interesting, as that is inline with the data, the chart above, but not the recommendation for 6x a day. Most important, remember that these results are in people eating plant poor diets, not a plant rich diet. Also, some of these recommended vegetables can be pretty high in oxalates, which may be an issue for some patients.
This is why I am much more concerned with giving people a hurdle/tweek that can be pretty challenging to do and which most of them can't do and maintain. We are asking them to do something that has no credible results and is not applicable to our population. Personally, if I had any concern, I would just ask them to follow the MWL plate, which would automatically increase their overall vegetable intake.
In Health
Jeff