Michael Greger MD

Michael Greger MD

Posted March 8, 2012

Published in Health

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Ask the Doctor: Q&A with Michael Greger, M.D. (#20)

Read More: alcohol, anorexia, beet juice, beets, beta carotene, caffeine, cancer, cardiac, carotenoderma, carrots, dementia, diabetes, dioxins, fish, fruit, glycemic index, greens, heart, hypothyroidism, jaundice, jenkins, kidney disease, mercury, phytonutrients, salmon, skin, stroke

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This is another sampling of the more than 900 comments and questions I’ve responded to on the site (so far!). Please feel free to leave any follow-up questions here or on any of the hundreds of videos on the more than a thousand topics covered on And remember, there’s a new video posted every weekday, so to make sure you don’t miss any:

Amy Freudenberg Dover asked on the Facebook pageNot necessarily related to beets, but related to how certain veggies and fruit cause skin colorations. My palms and soles of my feet are orange. I know this is from beta carotene. Is it cause for concern? It got better for awhile, but I noticed they are very orange again :(

Sounds like you have carotenoderma, caused by the buildup of carotenoid phytonutrients in your skin.  The condition itself is harmless, but if you haven't increased your vegetable intake in the last month or two (juicing carrots is a common cause) and there's still a significant increase in coloration then you should check with your doctor to make sure you're not suffering from secondary carotenoderma, in which the high levels in your skin are not because you're eating a lot, but because there may be an underlying disease state such as hypothyroidism, anorexia, diabetes, or kidney disease that is increasing levels in your blood stream. Carotenoderma can also sometimes be confused with jaundice, a sign of liver dysfunction, but the two can be differentiated by looking at the whites of the eyes; they which remain white in carotenoderma, but turn yellow in jaundice. For more on carotenoid deposition in the skin see Golden Glow and Produce, Not Pills.

Duke asked on Ask the Doctor (#19)I started being plant based after Thanksgiving. The principal reason is for my health and hopes to reduce or eliminate some day all my meds. One area that I’ve never seen any reference to is diet and atrial fibrillation. Is there any connection? Can diet begin to replace cumadin or pradaxa?

Atrial fibrillation is the most common clinical cardiac arrhythmia, an irregularity of our heart beat rhythm, which can set you up for a stroke, increase your risk of dementia and heart failure, and significantly shorten our lifespan. Previous findings on the effect of diet have been conflicting. Some studies have found alcohol, caffeine and fish consumption to be good in terms of preventing or resolving atrial fibrillation, and other studies have shown them all to be bad. It’s when this kind of situation arises in nutritional science, you pull out the big guns and put it to the test in one of the bigger better studies, like the famous Framingham Heart Study population, which is what was recently done. They found no effect either way in general from the consumption of alcohol, caffeine, or fish, but when they looked closer they observed an association between the consumption of dark fish and atrial fibrillation. A 6-fold higher hazard ratio for those eating a lot of fish like salmon, swordfish, bluefish, mackerel, and sardines. They conclude that their findings may suggest a “true adverse effect of dark fish and fish oil on certain subtypes of atrial fibrillation,” proposing that “potential toxins such as dioxins and methyl mercury accumulated in certain fish may have a negative effect on cardiac arrhythmia.”

There’s less out there about treatment, but a recent study did find that those with atrial fibrillation with higher intakes of antioxidants did have 80% greater odds of spontaneously reverting back to a normal heart rhythm. Until that happens your physician will likely want you to continue to take those two anticoagulants. My video Antioxidant Power of Plant Foods Versus Animal Foods offers an overview on which foods to choose to maximize antioxidant intake, though since you’re already eating a plant-strong diet, check out Antioxidants in a Pinch for a tip on taking it to the next level. Just make sure not to increase your dark green leafy vegetable consumption while on coumadin without your physician helping you titrate your drug dose.

azwildcat76 asked on So Should We Drink Beet Juice Or Not?As an endurance athlete I thought that beets/beet juice was my little secret but now you’ve let the cat out of the bag so to speak. I am curious if you had any comments on Dr. Ferenczi’s early Hungarian studies on the use of beets/beet juice to combat cancer?

I see Dr. Ferenczi has published papers in both Hungarian and German. Anyone out there willing and able to translate them for me if I send you the PDFs? For an overview of my beet videos, see my blog yesterday at One Green Planet: Using Greens to Improve Athletic Performance.

CapeBreton asked on So Should We Drink Beet Juice Or Not?I was surprised to see you reference a paper by Eaton on so called “Paleolithic nutrition.” These folks are part of a group who argues that we (humans) need to eat lots of meat to be healthy because that is built into our genes…..despite the overwhelming evidence that eating less (or no) meat promotes better health and that there are no nutrients except B12 not effectively obtained from a plant based diet.

David Jenkins is more convincing in arguing our genetic heritage is more likely rooted in the Miocene, with a diversity of plant foods at the root of our diet.

I have tremendous respect for Dr. Jenkins and his “ape diet” (also known as the Portfolio Diet) that I refer to in Low Fat or Whole Food. He was the guy who came up with the glycemic index concept. He was a co-author of the seminal review I covered in Egg Cholesterol in the Diet and my zombie-themed Avoiding Cholesterol is a No-Brainer. He’s also the one behind the plant-based “Eco-Atkins” diet (Plant-Based Atkins Diet). The full text of the commentary you mention is available at The Garden of Eden: Plant-Based Diets.

mercman40 asked on The Best NutBeen drinking as replacement for cow milk, love the taste, etc. However, I do buy the Vanilla sweetened flavor…is that bad?  Am I taking away from the good of it all?

Almond milk is certainly superior to calf’s milk, if only because of the lack of saturated animal fat, cholesterol, and hormones (see, for example, my videos Acne & Cancer Connection and Trans fat, saturated fat, and cholesterol: Tolerable upper intake of zero), but is unflavored, unsweetened almond milk preferable to sweetened vanilla? In general, I’m in favor of cutting down on intake of empty calories whenever possible. We only get about 2,000 in the calorie bank every day–why not try to make them count? So almond milk versus almond milk with added sugar is a no-brainer decision for me, but I guess it depends on what you’re using it for. If the only way you would drink green tea is with the sweetened variety, then overall it would be healthier for you to stick with the added sugar (though your taste buds would probably adapt to the unsweetened variety, or you could try adding a harmless noncaloric sweetener such as erythritol (see A Harmless Artificial Sweetener). The vanilla question is interesting, though. Given its popularity, I was surprised there wasn’t more science published on the health effects of vanilla orchid fruit phytonutrients. There are two in vitro studies that suggest vanillin, one of the many aromatic compounds in vanilla, may be protective against colorectal and cervical cancer, but no clinical or epidemiological studies have been published to my knowledge. There was also a study showing that vanilla extract may interfere with bacterial communication, concluding vanilla “might promote human health by…preventing bacterial pathogenesis.”

The most unusual vanilla study may be one published out of Germany in 1999. Researchers wanted to know how if our olfactory memory goes back even further than our verbal memory. Do we subconsciously remember tastes and smells from our infancy before we could even put them into words? They realized that there was a time certain German infant formulas were flavored with vanilla, so they challenged a group of adults with a vanilla-containing food. But they couldn’t just use your typical vanilla flavored confection because it could introduce too many other new variables. They had to choose something that no one would have ever associated with vanilla. So they concocted… vanilla-flavored ketchup! And guess what? Two-thirds of those bottle fed with vanilla as infants preferred the vanilla ketchup, whereas two thirds of the rest were like “blech!” and chose the regular ketchup. The moral of the story is that perhaps if breastfeeding women eat lots of healthy foods, their broccoli-flavored breast milk might get remembered years down the road.