Non-Starchy Veggies, Leafy Greens & You: How Much Is Enough

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Non-Starchy Veggies, Leafy Greens & You: How Much Is Enough

Postby JeffN » Wed Mar 11, 2015 6:47 am

Non-Starchy Vegetables, Leafy Greens & You: How Much Is Enough?

How many non-starchy vegetables and leafy greens should you eat in a day? A few servings? A few pounds? or Six times per day? Should we eat them at every meal? What about for breakfast? Should they be a side dish or a main meal? And, when we discuss amounts, are we talking about servings, visual volume or calories? Someone could go "kale crazy" trying to figure it all out.

Here are a few articles and discussions to help you cut through the confusion. Take the time to read through them all to help put this issue in proper perspective & context. In addition, I have added a few posts below that have actually broken out the math.

How Many Non-Starchy Veggies Should We Eat?
https://www.drmcdougall.com/forums/view ... 22&t=42701

How Much Kale Does It Really Take To Reach Nutrient Nirvana?
http://www.drmcdougall.com/forums/viewt ... 22&t=28413

Eating Greens & Nitric Oxide Production
https://www.drmcdougall.com/forums/view ... 22&t=44548

Leafy Greens 6x/Day? (Followup to "nitric oxide production")
https://www.drmcdougall.com/forums/view ... 22&t=44556

Leafy Greens 6x/Day? Redux
https://www.drmcdougall.com/forums/view ... 22&t=55369

My Review of the Eating Greens study on Okinawa Women that Dr Esselstyn quotes
https://www.drmcdougall.com/forums/view ... 13#p377385

Clarifying the Confusion: Dr Esselstyn Responds
http://www.jeffnovick.com/RD/Q_%26_As/E ... ponds.html

McDougall’s Moments: The All-Vegetable Diet?
https://www.drmcdougall.com/health/educ ... able-diet/

The Healthy Eating Placemat:A Visual Guide To Healthy Eating
https://www.drmcdougall.com/forums/view ... 22&t=37450

A Day In The Life
https://www.drmcdougall.com/forums/view ... 22&t=43281

Better to eat many different foods or a limited variety?
https://www.drmcdougall.com/forums/view ... 9&p=439451

When Low Risk Means High Risk & Hi Benefit Means No Benefit
https://www.drmcdougall.com/forums/view ... 22&t=43681

The Calorie Paradox: Is Your Plant Based Diet A Vegetable Based, Nut Based or Starch Based Diet?
http://www.jeffnovick.com/RD/Articles/E ... _Diet.html

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Re: Non-Starchy Veggies, Leafy Greens & You: How Much Is Eno

Postby JeffN » Sat Sep 18, 2021 7:41 am

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#p377385

It 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).

Image

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.

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Re: Non-Starchy Veggies, Leafy Greens & You: How Much Is Eno

Postby JeffN » Thu Dec 16, 2021 12:00 pm

JeffN wrote: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.



A recent meta-analysis of 19 studies. Turns out a single dose was more effective than using multiple dosing throughout the day so even if you think this is of value to you, a single dose (which anyone following the MWL will be getting, is more then enough.

"However, the ES in studies using an acute dose (i.e., 0.54, 95% CI 0.37, 0.71; p = 6.774 × 10- 12) was greater (p = 0.0211) than in studies using a multiple dose regimen (i.e., 0.22, 95% CI 0.01, 0.43; p = 0.003630)."


Effect of dietary nitrate on human muscle power: a systematic review and individual participant data meta-analysis
Review J Int Soc Sports Nutr
2021 Oct 9;18(1):66. doi: 10.1186/s12970-021-00463-z.
PMID: 34625064 PMCID: PMC8501726 DOI: 10.1186/s12970-021-00463-z

https://www.ncbi.nlm.nih.gov/labs/pmc/a ... MC8501726/

Abstract

Background: Previous narrative reviews have concluded that dietary nitrate (NO3-) improves maximal neuromuscular power in humans. This conclusion, however, was based on a limited number of studies, and no attempt has been made to quantify the exact magnitude of this beneficial effect. Such information would help ensure adequate statistical power in future studies and could help place the effects of dietary NO3- on various aspects of exercise performance (i.e., endurance vs. strength vs. power) in better context. We therefore undertook a systematic review and individual participant data meta-analysis to quantify the effects of NO3- supplementation on human muscle power.

Methods: The literature was searched using a strategy developed by a health sciences librarian. Data sources included Medline Ovid, Embase, SPORTDiscus, Scopus, Clinicaltrials.gov , and Google Scholar. Studies were included if they used a randomized, double-blind, placebo-controlled, crossover experimental design to measure the effects of dietary NO3- on maximal power during exercise in the non-fatigued state and the within-subject correlation could be determined from data in the published manuscript or obtained from the authors.

Results: Nineteen studies of a total of 268 participants (218 men, 50 women) met the criteria for inclusion. The overall effect size (ES; Hedge's g) calculated using a fixed effects model was 0.42 (95% confidence interval (CI) 0.29, 0.56; p = 6.310 × 10- 11). There was limited heterogeneity between studies (i.e., I2 = 22.79%, H2 = 1.30, p = 0.3460). The ES estimated using a random effects model was therefore similar (i.e., 0.45, 95% CI 0.30, 0.61; p = 1.064 × 10- 9). Sub-group analyses revealed no significant differences due to subject age, sex, or test modality (i.e., small vs. large muscle mass exercise). However, the ES in studies using an acute dose (i.e., 0.54, 95% CI 0.37, 0.71; p = 6.774 × 10- 12) was greater (p = 0.0211) than in studies using a multiple dose regimen (i.e., 0.22, 95% CI 0.01, 0.43; p = 0.003630).

Conclusions: Acute or chronic dietary NO3- intake significantly increases maximal muscle power in humans. The magnitude of this effect-on average, 5%***,is likely to be of considerable practical and clinical importance.

*** - the effect size reported in the present study (i.e., 0.45) is substantially larger than what’s been reported for other measures of physical performance. This includes muscular strength (0.08), time-trial performance (0.086), muscular endurance (0.31),[14] and performance during time-to-exhaustion tasks (0.32).[13][14]
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