The Probiotic Effect: Sexy, Slim Mice, Healthier Humans


Maybe we all should be stocking up on yogurt.

Researchers at Massachusetts Institute of Technology (MIT) studying probiotics and obesity found that mice who were fed vanilla yogurt were not only slimmer with silkier, shinier fur (the sleek little guy on the left in the photo), they were also more fertile.

The male mice had bigger testicles and more attitude -- "swagger," was how the MIT scientists described it -- and the females gave birth to bigger litters and were better moms.

ABC News reports that MIT researchers Eric Alm and Susan Erdman were looking at whether the healthy bacteria called probiotics that are often found in yogurt (and in our intestines) could help fight obesity, perhaps by aiding digestion.

According to Scientific American, the researchers took a group of 40 male and 40 female mice and either fed the animals a diet designed to mimic junk food in humans (high-fat, low-fiber, low-nutrient) or the normal mouse diet.  They then supple­mented half of each diet group with vanilla-flavored yogurt.

Much to the researchers' surprise, the yogurt-eating males had testicles 5 percent heavier than those of their non-yogurt eating counterparts on a regular mouse diet, and 15 percent heavier than those of the junk-food mice.

These well-endowed males also inseminated their partners faster and produced more offspring.

As for the females, they had even shinier coats than the males and were better moms to their bigger litters.

"We think it's the probiotics in the yogurt," Alm told ABC News.  "We think those organisms are somehow directly interacting with the mice to produce these effects."

Probiotics also got a boost in a new research review that found that people who are on antibiotics and take over-the-counter probiotic capsules are less likely to get diarrhea.

Reuters reports that researchers at the nonprofit research organization RAND found that patients were 42 percent less likely to get diarrhea from their antibiotic drugs if they were also taking a probiotic, as compared to those not taking probiotics.

In tackling infection, antibiotics also kill off a lot of the good bacteria we have in our gut, "so things kind of go haywire," researcher Sydne Newberry told Reuters.

The probiotic pills, which contain high amounts of the bacteria found in some yogurt products, help replace the missing bacteria in the intestines.

The researchers, however, couldn't tell from the studies whether one type of probiotic worked better than another because most of the studies used a mix of bacteria strains. The most common probiotics used were related to Lactobacillus, including acidophilus capsules.

Could eating yogurt produce the same beneficial effect? Possibly.

However,  Newberry notes that commercial yogurts vary widely in the amount of probiotics they contain, and carton labels aren't much help:  They don't list the amount.

In other health news:

New worries for women taking bone drugs. The debate over the safety of bone-building drugs like Fosamax and Boniva was raised again Wednesday when the Food and Drug Administration published an analysis that suggested caution about long-term use of the drugs, the New York Times reports. Although the FDA didn't issue specific recommendations, it did say that women at low risk for fracture or with a bone density near normal may be able to stop therapy after three to five years, but older patients at higher fracture risk and bone density "in the osteoporotic range" may benefit from continued therapy.

Mid-life depression linked to dementia. People who have symptoms of depression when they're middle-aged may be at increased risk of dementia decades later, reports Researchers used medical records of 13,000 Californians in their 40s to their 80s and found that late-life depression was linked with Alzheimer's disease, while mid-life depression was mostly connected with a related condition known as vascular dementia.

Be careful where you put that grocery bag. A reusable grocery bag stored in a hotel bathroom caused an outbreak of norovirus-induced diarrhea and nausea -- aka the "cruise ship virus" -- among nine of 13 members of an Oregon girls' soccer team, reports the Los Angeles Times. The highly contagious virus was found on the bag, which had been used to hold snacks. The bag, unfortunately, had been stored in the bathroom of the hotel room where the first girl to get sick had been staying.

Photo credit: Courtesy Susan Erdman, MIT

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