THE BLOG
07/29/2014 05:54 pm ET Updated Sep 28, 2014

4 Summer Foods That Can Help Trim Your Waist

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If you haven't heard about the microbiome, which The Mayo Clinic calls "the most important discovery since germ theory and genetics," let me tell you a bit about it before revealing what fresh and delicious summer foods will help you shed those hard-to-lose pounds that may have accumulated around your midsection.

The microbiome is a rich hidden universe of trillions of bacteria that live within and all around us. It turns out that there are 10 times more bacteria in and on our bodies than there are human cells! Much of this bacteria is extremely beneficial, especially the bacteria in our gut, as it controls our metabolism, our appetite, and even regulates our mood by aiding in the production of serotonin and other brain chemicals.

For the past eight years there's been a lot of research on the microbiome that I've put into clinical practice with astounding results. I've learned that there are certain foods that produce and nourish "friendly" bacteria and others that help eliminate the unfriendly bacteria that might be making it difficult for you to lose weight. Many of my patients have seen dramatic changes in their bodies and in their overall health when they follow the microbiome diet, which includes these four summer foods.

TOMATOES are a prebiotic, which means they help nourish the good bacteria that's already in your gut, replenishing the crucial lining of the intestinal walls. They are rich in inulin, arabinogalactans, and fructooligosaccharides.

Filled with dietary fiber that nourishes your microbiome while supporting your digestion and leaving you feeling full, tomatoes bright red color indicates that they are full of lycopene, an outstanding anti-oxidant. The vitamin C in tomatoes adds to its antioxidant protection. They are also rich in vitamin A, which is an important gut-healing vitamin in addition to all its other benefits. Tomatoes lower cholesterol and triglycerides, and they reduce platelet stickiness, giving them great cardioprotective benefits. Last but not least, tomatoes are also good for bone health, so they are a terrific addition to your diet if you are at risk for osteoporosis.

Tips for Buying and Preparing Tomatoes:
Summer is the only time to buy fresh, juicy tomatoes. It's important to smell them on the theory that if it doesn't smell like a tomato, it won't taste like one. Look for tomatoes that are bright red, firm but not mushy or woody.

BLUEBERRIES contain loads of antioxidants like Anthocyanin, vitamin C, B complex, vitamin E, vitamin A, copper, selenium, zinc, and iron which boost your immune system and prevent infections. They also contain anthocyanin, a pigment that gives them their blue color. A recent University of Michigan Cardiovascular Center study suggests that blueberries may help reduce belly fat and risk factors for cardiovascular disease and metabolic syndrome.

Tips for Buying Blueberries:
Choose blueberries that are firm and have a uniform color with a whitish bloom.

ASPARAGUS is another prebiotic. It contains oligosaccharides, fibers which help beneficial bacteria in the gut flourish. Short-chain fatty acids (SCFAs) are one of your microbiome's most potent weapons for fighting fat, preserving health, and revving up your metabolism. SCFA's are produced when the bacteria in your microbiome feed on oligosaccharides making it all the way to your colon "undigested." When you eat asparagus it's as though you're sending dinner down to your microbiome, whose bacteria feast on these fibers by fermenting them. The byproducts of that fermentation--the SCFA's--include acetate (acetic acid) and butyrate (butyric acid), as well as B vitamins and vitamin K. One of your dietary goals is to eat enough oligosaccharides and other prebiotics to keep the "good" bacteria in your microbiome well-fed and happy.

Butyrate is a kind of metabolic wonder drug. It improves insulin sensitivity while increasing energy expenditure: the amount of your fat that is burned off as energy. It modulates your immune system to protect you against infection and disease while supporting the integrity of your epithelium, preventing leaky gut. High levels of butyrate also offer effective prevention against inflammation.

LEEKS are high in dietary fiber to nourish your microbiome, and also high in flavonoids, the antioxidants that support cellular function. They have a lot of manganese, which produces digestive enzymes, as well as high quantifies of vitamin A, which is key for healing your gut wall. They are also high in folate and B6, which supports brain function. Folate is the active version of folic acid. Some people have difficulty converting folate to methyl folate, the active form in the body, so by providing extra folate directy from leeks, they can better nudge their metabolism in the right direction.

Another amazing quality of leeks is their high quantity of kaempferol, which protects us against cancer and cardiovascular disease. It helps us to lower blood pressure in two ways: by supporting nitric oxide production, and by decreasing our body's production of a compound that blocks nitric oxide production. Leeks also contain polyphenols, which support blood vessel health. Last but not least, they help decrease homocysteine, which can interfere both with your cardiovascular system and with your brain.

Tips for Buying and Preparing Leeks:
Leeks look sort of like giant scallions -- large green tubes of coiled green skin. They taste very similar to onions, but they have a stronger, greener taste. Look for fresh, green leeks -- they should not appear wilted or pale.

In addition to eating these four foods, I encourage my patients to eat foods or take supplements that contain probiotics, the microscopic organisms that replenish the microbiome. You can find probiotics in cultured and fermented foods that contain live bacteria: raw sauerkraut, kimchee, pickled vegetables, goat's or sheep's milk kefir and yogurt without sugar. Probiotics can help you lose both pounds and inches. Significantly the fat that is lost tends to be visceral fat -- the highly dangerous fat wrapped around your organs that makes your abdomen bulge.

Raphael Kellman, M.D. is the author of The Microbiome Diet and the founder of the Kellman Center for Functional and Integrative Medicine. For more information visit raphaelkellmanmd.com.

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