The You Docs: Can Belly Bacteria Cause Weight Gain?

Despite a healthy and low calorie eating plan and spending eight to 10 hours a week at the gym, I have gained 20 pounds in a year. I think this is connected to my gut. The only time I lost significant weight was after taking the Flagyl antibiotic. I lost 40 pounds in a year without changing my eating or exercising. But then I started to win again. Could my weight gain be caused by intestinal bacteria?

Flagyl from $0.26

– Ellen, by email

Do Belly Insects Make You Fat? No, it’s not a crazy excuse. There is laboratory evidence that certain microbes in the stomach can “infect” you with flab. Researchers have found that mice lacking a certain protein are about 15 percent heavier than other mice and have more than one intestinal bug that causes the calories to be stored as fat. They also have increased inflammation throughout the body, which is linked to heart disease, diabetes and cancer. Worse still, they have metabolic syndrome, which in humans is characterized by belly fat, high blood sugar, high blood pressure and high LDL (the bad type). Our official medical reaction to that: Yeesh.

Before blaming your belly bulge entirely on tummy bugs, consider this: You can encourage those microbes that boost fat by eating sugary foods. No buff. It is easy to overdo the sweet carbohydrates that microbes love while still eating low calories. A replacement food bar we saw had only 180 calories but over 3 teaspoons of sugar!

To nix those bad store fat bugs, try a good bacteria type probiotic supplement that is tough enough to survive your stomach acid. Dr. Mike likes Sustenex, Digestive Advantage and Culturelle. If you cut back on sugar and do not take probiotics, ask your doctor if you can try a short course of Flagyl, then take probiotics. (Flagyl has side effects, so taking it should not be your first choice).


I have been on a proton pump inhibitor for 20 years and still have acid reflux. My bones are not good, and I would like to lower the medications. Is there any alternative to relieve reflux?

– Beverly, by email

The PPI you have been using may have rejected the fire in your belly, but it clearly does not completely stop the acid from the stomach from traveling through your esophagus. It is smart to worry about your bone loss. There is evidence that PPIs weaken bones, in part by interfering with calcium absorption. Usually this increases the risk of fracture only in high doses or over a long period of time, but 20 years is a long time!

We suspect it’s time to kiss your PPI goodbye. Talk to your doctor about exchanging an H2 antagonist (“H” is for histamine) such as Zantac, Pepcid or Tagamet. There is evidence that H2 antagonists are not associated with fractures and may even protect bones. Along with changing meds, these tips can ease your reflux:

• Avoid foods that cause reflux, such as caffeine, chocolate, citrus, tomato products, total fat dairy products, carbonated beverages, alcohol and peppermint.

• Do not wear tight belts.

• Eat small meals.

• Reduce salt and fat.

• Eat more fiber – which means more fruits, vegetables and 100 percent whole grains.

• Chew sugarless gum after meals.

• If you are carrying extra pounds, lose at least 10 percent of your weight.

• Do not exercise right after eating.

• Do not eat and then hit the sack within three hours.

• Sleep with your head raised by laying the head of your bed on bricks.

• Do not take benzodiazepines (such as Valium or Xanax) for sleep.

Do you lose most of the fiber in fruits and vegetables when you juice them?

– Jean, Denver

Throwing fruits and vegetables into a buzzer juicer spells the death of much of your fiber. That is because the pulpy fiber is caught when the juice is extracted. Now, we DOCS do not oppose juicing in moderation.

And we are crazy about our own healthy smoothies. But we eat most of our fruits and vegetables whole.

Despite claims to the contrary in television commercials, juice does not make the nutrients more available to your body, and raw food enzymes do not have special powers, including the ability to survive the digestive acids of the stomach. In fact, if you have diabetes or are overweight, know that ounce of ounce, fruit and vegetable juices rich in starch are much higher in sugar than the whole foods from which they come.

Our bottom line: It is okay to occasionally drink your fruits and vegetables as long as you eat often, too.

You – Mehmet Oz and Mike Roizen – are authors of “YOU: On a Diet.”