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Burning Fat With Flavonoids

Nuts appear to boost one’s metabolism, such that when we eat nuts we burn more of our own fat to compensate. In my 2-min. video, Testing the Fat Burning Theory, I show that people who don’t eat nuts tend to burn off around 20 grams of fat a day–about 5 pats worth of butter, but those eating walnuts averaged more like 31 grams–7 or 8 pats of butter. In Fat Burning Via Arginine, I explore one theory as to why this may happen (and where arginine can be found in our diet).

It may also be the flavonoids, phytonutrients found in nuts as well as citrus, berries, red onions, beans, green tea, grapes, and cocoa, that may boost our metabolism enough to significantly slim our waistline. Based on what kind of evidence? I showcase a study done on purple grape juice in my video Fat Burning Via Flavonoids.

Just like nuts are calorically dense yet don’t seem to cause much weight gain, Welch’s was hoping that the same would be found for their grape juice. They had people guzzle down 2 cups a day for three months. Keep in mind that Welch’s grape juice has more sugar than Coca Cola. Two cups of purple grape juice contain the equivalent of 20 spoonfuls of sugar. The control group was basically given grape Kool-Aid instead, with the same number of calories and same amount of sugar, but no detectable phytonutrients.

At two cups a day study subjects were getting hundreds of extra calories a day. Surely after 3 months they’d gain a couple pounds. Indeed that’s what happened in the grape-flavored sugar water group—how could they not with all that extra sugar in their diet? The grape juice group, on the other hand, did not. In fact, their waist circumference shrunk significantly. Drinking grape juice appeared to burn away significantly more tummy fat. So maybe there is something to the theory put forth by the nut and green tea researchers that flavonoid phytonutrients are capable of helping the body burn fat. If true, then it’s just one more reason to eat nuts and drink green tea—not grape juice. Instead of the juice, I’d recommend eating concord grapes, the source of purple grape juice that you may be able to find at a farmer’s market near you.

-Michael Greger, M.D.

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Michael Greger M.D., FACLM

Michael Greger, M.D. FACLM, is a physician, New York Times bestselling author, and internationally recognized professional speaker on a number of important public health issues. Dr. Greger has lectured at the Conference on World Affairs, the National Institutes of Health, and the International Bird Flu Summit, testified before Congress, appeared on The Dr. Oz Show and The Colbert Report, and was invited as an expert witness in defense of Oprah Winfrey at the infamous "meat defamation" trial.

12 responses to “Burning Fat With Flavonoids

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  1. That’s interesting and good to know but nuts always put weight on my husband and I. Could it be once you’ve hit age 50 plus the metabolism is low and hopeless! We live on beans and greens and a handful of nuts plus exercise and still have to fight the weight.

    1. How many nuts you eat may be the factor in weight gain vs weight loss. Your daily intake of nuts should be the amount that you can put on the palm of your hand. The nuts should be flat on your palm and the nuts should not touch your fingers.

      I can’t control myself when it comes to nuts. I’ll eat half the can and then the weight starts to come on and my cholesterol goes up do to the saturated fats. I now avoid them per Dr. Caldwell Esselstyn’s advice.

    2. Hey Peppy, do you do weight training? Gaining and preserving lean muscle tissue is absolutely key for weight management as you age. This is because muscle has a tendency to break down as we age. If you do cardio but no weight training you are wasting your time. Get the weights out or go to a pump class at the gym 2 times a week.

    3. Are you getting your daily 7 MET-h of exercise? You could try doing a 24h water-fast once (or even twice) a week. I’ve been doing this for the past year and I eat more nuts than I should — still difficult to gain any weight. My BMI just won’t go over 25 no matter how much I eat. Before adopting a WFPB diet, my BMI was over 30.

  2. What about RAW vs ROASTED. Put the raw one in the ground and it may grow into a new plant. Put the roasted one in the ground in all it will do is decay back into the earth.

    Perhaps it is the Roasted nuts that make people gain weight. I know people think of nuts they think salt or sugar, oil, and roasted.

    On another note; It could indeed be a synergistic effect with they other important compounds found in these fat fighting foods.

    Great Article, Loved it. Thank you Dr..G for posting!

    1. Red wine is not as good as grape juice, due to the alcohol content, but grape juice is not as good as grapes, since the processing eliminates much of the fiber and nutrients. In general, alcohol is not good. And juicing is not good (better to eat the whole food).

  3. Following these holiday trends will be really enjoying. I celebrate my holidays with family and exchanging gifts is my way of celebrating it.

  4. I would be very interested to know which foods have the highest concentrations of flavonoids. How much does green tea have compared to fresh whole grapes?

  5. I cant tolerate nuts but my husband has eaten about a quarter cup (easier to control amount) of rotating ones most days for snack for over a year and his HDL has gone up (modestly but still) and his LDL is well within health per Mayo/ Cleveland Clinic/ Heart & Stroke etc. He also enjoys about a quarter of an avocado many days with his veggies. Here’s the interesting point…based on side effects he stopped his statin and baby aspirin (terrible nose bleeds and stomach issues) over 4 months ago before the blood work was done and while the LDL is higher, it’s actually lower then it was before going on it and still well within healthy. He also changed family doctors who is not sure why he was ever put on these drugs or why he sees a caridologist once a year. As his new physician said…you’re healthy as an ox! At 64 he’s healthier then he’s ever been. Granted he could exercise more and tweek his diet a bit more but he has slowly converted over to a mostly plant based whole foods based diet. He ever gave up his fave boxed cereal he’s eaten for years for oatmeal with a rotation of healthy ground seeds and unsweetened almond milk. Turns out the boxed cereal had molasses in it so when we added the good stuff (black strap unsulphured organic) to his oatmeal he LOVED it! Bonus it’s a good source of B6 which is good for his ADHD.

    My point is he avoided nuts, avocados etc for years based on warnings from his then docs. Now that he’s been back to enjoying them and mov(ing) away from animal protein sources including dairy (bad, bad for ADHD in many) he feels and looks better then in years. His new doc is going repeat blood tests every year to monitor but says there is no need for a statin or aspirin and encouraged his healthy nut snacking (non or dry roasted, organic etc.), avocado and so forth with room for indulgence. Im not saying this works for everyone and I avoid preaching. We all have to do what works for us. I do hope if there are others who were scared off enjoying nuts in there healthy form even on occasion they will reconsider. Life is short and you need to enjoy your food too. ; )

    1. BTW I realize the comment from Peppy is quite old but agree with the comment about weight training/ bearing below. It’s really important for the 50 over group. Some form twice a week would be great. Even some yoga poses build muscle. You can buy easy to follow DVDs if you’re not a gym/ class person (I’m really not). Do some internet surfing and you’ll find what grabs your interest. Just make sure you pick something you can actually enjoy (or learn to) so you’ll commit to it and you feel good about. Good luck.

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