Studies have already demonstrated that the intestinal flora of obese individuals differs from that of thin people. That difference may be due to the fact that a diet high in fat and low in fiber promotes certain bacteria at the expense of others.
Researchers tried to determine if the consumption of probiotics could help reset the balance of the intestinal microbiota in favor of bacteria that promote a healthy weight.
125 overweight men and women underwent a 12-week weight-loss diet, followed by a 12-week period aimed at maintaining body weight. Half the participants were given a probiotic that contained Lactobacillus rhamnosus while the other half received a placebo.
After the 12-week diet period, researchers observed an average weight loss of 4.4 kg (9.68 lbs) in women in the probiotic group and 2.6 kg (5.72 lbs) in the placebo group.
However, no differences in weight loss were observed among males in the two groups. Reserachers suggested perhaps it could be because the dose was too small, or that the study period was too short.
After the 12-week maintenance period, the weight of the women in the placebo group had remained stable but the probiotic group had continued to lose weight, for a total of 5.2 kg (11.44 lbs) per person.
The study concluded that women consuming probiotics lost twice as much weight over the 24-week period of the study.
Researchers also noted a drop in the appetite-regulating hormone leptin in this group, as well as a lower overall concentration of the intestinal bacteria related to obesity.