Dr. Michael Greger - 2015 Reddit IAMA Interview Excerpts


Dr. Greger, the creator of NutritionFacts and plant-based diet advocate, did an IAMA on Reddit in 2015. While this may be "last years news," it is still chalk-full of useful information. For those who are not aware, Reddit has a forum called IAMA that allows any user on the website to ask questions to all types of people ranging from celebrities to politicians to doctors, scientists, athletes, and more! Dr. Greger's responses to some of the questions put forth by his online audience are too hard to just ignore, so I felt compelled to throw a few together for you to easily digest here.

The full IAMA is available on Reddit, and be sure to check out our review of Dr. Greger's infamous book How Not to Die.

Dr. Greger's Reddit IAMA Excerpts:

1). Dr. Greger, what are your views on pseudoscience in the realm of nutrition and health? People like Vani Hari (the food babe) and Dr. Mercola have gotten extremely popular by manipulating, misusing, and misunderstanding basic science. Do you see that as a major problem in nutrition science? What do you think should be done?

MG,MD: Here's a quote from my new book that touches on this:

"Too much of the nutrition world is split into camps, each following their respective guru. What other field of serious scientific inquiry is like that? After all, 2 + 2 = 4 regardless of what your favorite mathematician thinks. This is because there isn’t a trillion-dollar industry that profits from confusing people about arithmetic. If you were getting conficting messages from all sides about basic math, in desperation, you might have to choose one authority to stick with, hoping that person will accurately represent the available research. Who has time to read and decipher all the original source material?

Early on in my practice, I decided that I didn’t want to rely on anyone else’s interpretation for what could ultimately be life-or-death decisions for my patients. I had the access, the resources, and the background to interpret the science on my own. When I initially began my annual reviews of the nutrition literature, it was really just to make myself a better doctor. But when I discovered such a treasure trove of information, I knew I couldn’t keep it to myself. My hope is to disseminate it in a way that removes me as much as possible from the equation. I don’t want to present the trademarked Dr. Greger Diet; I want to present the best-available-evidence diet. That’s why I show the original papers, charts, graphs, and quotes with links to all the primary sources in my Nutrition Facts.org videos. I try to keep my own interpretation to a minimum—though admittedly, I sometimes can’t help myself!

2). Hi Dr. Greger! I almost worked for you during your first round of hiring, but had to finish college! Your word is pretty much law in my household.

My question is based on a lot of people who have studied science and are quick to call out 'bad science'. Even those in the vegan community are wary of some of your contents' more bold claims. How do you ensure that you don't merely 'look for the answers you want' in studies, that the studies themselves are good, and that you remain unbiased? A friend of mine's favorite science quote is 'remember, a bullet will kill cancer cells in a petri dish'.

P.S. just bought your book How Not to Die; can't wait to dig in!

MG,MD: Science today is indeed fraught with fraud, bias, sloppiness, and conflicts of interest. Quietly shelving and burying unfavorable outcomes, inappropriate interpretations, etc. but I figure it’s like that Winston Churchill quote “Democracy is the worst form of government—except for all the others." One could say the peer-reviewed scientific literature these days is the worst form of evidence... except all the others… How else can we make life or death decisions for ourselves, our families, and our patients but by the best available balance of evidence?

In terms of "my" claims, I really try not to make any on NutritionFacts.org, but rather let the science speak for itself. My videos are basically just showing all the original papers and include links to all the sources cited so people can make up their minds for themselves.

I hope that answers your question?

Hope you like the book!

3). Why have you found plant-based eating to be healthier than diets heavy with meat?

MG,MD: I think that's what the balance of peer-reviewed scientific evidence shows. One can look at population studies, like seeing what the healthiest and most long-lived populations eat (the so-called "Blue Zones"). For example, my video The Okinawa Diet: Living to 100. Or go all the way to randomized controlled trials, like Dr. Dean Ornish's Lifestyle Heart Trial, that showed that a plant-based diet and other healthy lifestyle changes can reverse heart disease, our leading cause of death. In fact it's the only diet that has ever been proven to reverse heart disease in the majority of patients. So seems like maybe that should be the default diet until proven otherwise--after all, a cure for our #1 killer? And the fact that it has also been shown to reverse other chronic diseases like hypertension and type 2 diabetes would seem to make the case overwhelming.

What do you think of the raw vegan movement? Do you think that it is worth it?

MG,MD: The reason I think one might see some benefits early on eating predominantly raw is that by definition it means you're cutting out processed food and junk. So compared to a vegan living off of french fries and vegan doughnuts, someone eat a raw vegan diet would do much better. The important thing is to try to eat lots of whole plant foods. I don't know of any data suggesting eating exclusively raw has benefits over a a diet composed of largely whole plant foods, both raw and cooked. I am concerned about AGEs, though, and so though I love them, in my own diet I've been roasting my nuts less. See, for example, my video Reducing Glycotoxin Intake to Prevent Alzheimer’s.

5). Do you have any general tips for people who are already vegan on how to make sure they stay healthy?

MG,MD: The most important thing vegans can do is to make sure to ensure a regular reliable source of vitamin B12. See, for example, my video Vitamin B12 Necessary for Arterial Health.

Probably the easiest way is to take one 2,500 mcg (µg) cyanocobalamin supplement once each week. Can cost less than $5 a year, but is absolutely critical (unless eating enough B12-fortified foods). Our fellow great apes get the B12 they need from bugs, dirt, and feces but I prefer supplements! :)

Thank you for your amazing content and well-produced videos, Dr. Greger. I especially like the year-in-review talks. I identify as "mostly vegan". Why I'd prefer 100% vegan, I find it to be a difficult lifestyle in social settings and even in my otherwise non-vegan family.

My question is: how much of an occasional deviation from vegan diet is detrimental to one's health? Does an occasional salmon dish, or butter in the paste, or the eggs in a pastry negate all the benefits of otherwise whole-food vegan diet?

MG,MD: Fabulous question! There was a study involving four thousand participants that compared traditional Asian diets with and without occasional servings of meat. The researchers found that men who avoided meat altogether had only half the odds of diabetes compared to those eating a serving of meat every few days, and the vegetarian women had 75% lower odds of diabetes than women who were otherwise vegetarian but averaged a single serving of meat a week. We don’t know exactly where that dividing line is, but we do know based on the Adventist data that vegetarians who start to eat meat at least once a week appear to experience large increases in the risk of heart disease, stroke, diabetes, and weight gain. During the twelve years after the transition from vegetarian to omnivore, meat-eating was associated with a 3.6 year decrease in life expectancy.

From a nutrition standpoint, I’d much rather see people eat, for example, the traditional Okinawan diet, which is largely (but not exclusively) plant-based, than the strictest 100% vegan diet centered around french fries and vegan Doritos.

Unprocessed plant foods are the healthiest options, so the more we can squeeze into our daily diet the better. Health-wise it doesn’t really matter what we eat on holidays or special occasions; it’s our week-to-week choices that makes the most difference for our long-term health and longevity. Sounds like you're doing better than 99.99% of Americans so congratulations and keep it up!

Do you see the AMA moving to or away from lifestyle and diet as medicine given the huge influx of dollars from drug companies?

MG,MD: An AMA about the AMA--love it!

Sadly, the American Medical Association has a shameful history of being beholden to corporate interests at the expense of patient health. See for example starting around minute 1:04 in my annual year-in-review video, where I talk about the AMA withholding support from the Surgeon General's report on smoking after receiving a $10 million grant form the tobacco industry.

But slowly but surely, things are changing. There are now nutrition based medical conferences (here and here). The current President of the American College of Cardiology walks the walk (I use one of the quotes attributed to him in this article. When he was asked why he follows his own advice to patients to follow a plant-based diet, he reportedly answered: "I don’t mind dying. I just don’t want it to be my fault."). And look at what Kaiser Permanente put out in What Diet Should Physicians Recommend?. These are reasons to be optimistic!

8). What are your thoughts on the book The China Study by Dr. T. Colin Campbell? I read that book and was completely blown away by the information. I have been on a WFPB Vegan diet for 4 months now, and love it! Was his work influential in your own research at all?

MG,MD: Dr. Campbell is one of the reasons I went to study at Cornell! He's long been an inspiration to me. If you're interested, I quote a bit from his writings in my video China Study on Sudden Cardiac Death.

9). What is your favorite dinner recipe?

MG,MD: In my attempts to be as efficient as possible in all areas of my life, I like checking off as many boxes as possible of my Daily Dozen at one time, so in the book I include my "Eight Check-Mark Pesto" recipe:

  • 2 cups fresh basil leaves
  • 1⁄4 cup freshly toasted walnuts
  • 2 cloves fresh garlic
  • 1⁄4 of a peeled lemon
  • 1⁄4 teaspoon lemon zest
  • 1⁄4 inch of fresh turmeric root (or 1⁄4 teaspoon turmeric powder)
  • 1⁄4 cup pinto beans
  • 1⁄4 cup water or liquid from bean can
  • 1 tablespoon white miso
  • Pepper to taste

Combine all ingredients in a food processor. Blend until smooth. Scoop onto a cup and a half of cooked whole-grain pasta.

Ok, now you made my hungry :)

10). I've never considered potatoes to be so controversial ... until now. Dr. John McDougall, for example, laudes the potato as one of the most healthful foods, while others such as yourself have a different idea, going as far as to say they are toxic. What's the verdict, doc - will potatoes, sweet potatoes, and possibly yams - boiled or baked - make me regret eating them regularly (say, three to four nights per week)? Thanks for all your kind work.

MG,MD: Sweet potatoes (which in the U.S. is synonymous with "yam") are one of the healthiest foods on the planet! Even better, purple sweet potatoes! That's actually one of my favorite snacks. After scrubbing some purple-fleshed potatoes I cut them into wedges, sprinkle some malt vinegar on them, dredge them in a mixture of blue cornmeal and powdered rosemary and bake them until they're mashed potato soft inside. Then dip them in hot sauce spiked ketchup--yum!

Dr. Greger's full IAMA is available on Reddit. Hopefully you have enjoyed some of the responses provided here in an easier to digest format. Dr. Greger serves as a great inspiration and is often viewed as a respected leader of the plant-based movement. I've had the chance to meet him in the past, and my perspective then was that he seemed like a reasonable, down-to-earth person with a passion for helping to educate people about how they can make their lives inherently better.