Certain phytonutrients may tip the balance of healthy gut bacteria in favor of flora associated with improved weight control.
Tipping Firmicutes to Bacteroidetes,
Other than fiber, what else do plants make that animals don’t that could help account for how dramatically slimmer those who eat a plant based diets tend to be? Phytonutrients! Mammals including humans harbor two main types of friendly gut bacteria: Bacteroidetes and Firmicutes. In terms of obesity though one appears friendlier than other, there is mounting evidence that the gut flora is different in healthy patients than it is in obese patients, which primarily involves higher numbers of Firmicutes than Bacteroidetes in the case of obesity and overweight. Just to keep them straight so you can remember, fatter is Firmicutes and boney is Bacteroidetes.
Obese individuals seem to have more Firmicutes than Bacteriodetes in their guts. If you put people on a diet for a year, you can actually change the proportion. Give people certain antibiotics, may actually trigger obesity because we are mucking around down there. How can we improve our ratio? There is a class of phytonutrients called polyphenols that do two things: they preferentially feed Bacteriodetes while simultaneously suppressing the growth of Firmicutes.
So researches said, hey maybe that’s why the use of vinegar has been recommended for thousands of years for weight loss! And it’s often made out of wine vinegar and apple cider vinegar, both of which have grapes and apples packed with polyphenols. The weight lowering properties of fruits, green tea and wine vinegar in obese people may be partly related to the polyphenol content of them which consequently changes the gut flora, which may consequently alter the balance between the two groups of Bacteroidetes and the Firmicutes bacteria in the favor of Bacteroidetes.
It’s funny… opponents to the power of phytonutrients often point to studies showing that up to 85% of those wonderful blue anthocyanins in blueberries end up in your colon unabsorbed. But that may be exactly where the magic happens.
To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring watch the above video. This is just an approximation of the audio contributed by MaryAnn Allison.
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This is the third of a three-part video series on keeping our gut bacteria happy. The first two discussed propionate and butyrate, two health-promoting short chain fatty acids produced by the fermentation of fiber that may be helpful in preventing obesity, cancer, and inflammation in general. This is a follow-up to similar studies comparing gut flora between populations eating different diets I talked about ages ago in Gut Flora & Obesity. More on phenolic phytonutrients in Best Fruit Juice. Vinegar may also help with weight loss via another mechanism detailed in my video Is Vinegar Good For You?. Blueberries may be helpful in Improving Memory Through Diet, but are they the Best Berries?
For some context, please check out my associated blog posts: The Ice Diet and Eating Green to Prevent Cancer
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