Taking probiotics during pregnancy prevents obesity, according to a new study presented at  the 17th European Congress on Obesity in May. According to researchers, one year after giving birth, women were less likely to become obese if they had taken probiotics starting from the first trimester of pregnancy.

In recent years, nutritionists and health experts have labelled probiotics as superfoods. They maintain a healthy balance of bacteria in the digestive tract and fight the growth of harmful bacteria. They also help treat a range of intestinal diseases and play a role in controlling inflammation. Now, obesity researchers have started to investigate whether the balance of bacteria in the gut is a contributing factor to being overweight and whether adjusting the balance would help to fight these two conditions.  

"Central obesity, where overall obesity is combined with a particularly fat belly, is considered especially unhealthy," said Kirsi Laitinen, a nutritionist and senior lecturer at the University of Turku in Finland who presented the study. "We found it in 25 percent of the women who had received the probiotics along with dietary counselling, compared with 43 percent in the women who received diet advice alone."

In the study, 256 women were divided into three groups during the first trimester of pregnancy. Two of the groups received dietary counselling consistent with recommendations for healthy weight gain and optimal fetal development during pregnancy. They were also given food such as spreads and salad dressings with monounsaturated and polyunsaturated fatty acids, and fiber-enriched pasta and breakfast cereal to take home.

One of the groups received daily capsules of probiotics containing Lactobacillus and Bifidobacterium, the most commonly used probiotics. The second group received dummy capsules. And the third group received dummy capsules and no dietary counselling. The capsules were continued until the women stopped exclusive breastfeeding.

Twenty-five percent of the women who had taken probiotics and diet advice had central obesity, which is defined as a body mass index (BMI) of 30 or more or a waist circumference over 80 centimeters (just over 31 inches). By comparison, central obesity was present in 43 percent of the women who received dietary counselling alone and in 40 percent of women who received neither diet advice nor probiotics. The average body fat percentage in the probiotics group was 28 percent, compared with 29 percent in the diet advice only group and 30 percent in the third group.

One of the limitations of the study was that it did not control for the mothers' weight before pregnancy, which may influence how fat they later became. As an aside, the Institute of Medicine (IOM) issued new guidelines in May on the amount of weight an expectant mother should gain during pregnancy. The pregnancy weight-gain guidelines remained the same for underweight, normal weight and overweight women, but the IOM added a new category for obese women, recommending a narrow range of weight gain - only between 11 and 20 pounds during pregnancy.

Laitinen and her colleagues will continue to follow the women and their babies to see whether giving probiotics during pregnancy has any influence on health outcomes in the children.

"The advantage of studying pregnant women to investigate the potential link between probiotics and obesity is that it allows us to see the effects not only in the women, but also in their children."

Particularly during pregnancy, the impact of obesity can be immense, with the effects seen both in the mother and the child, said Laitinen. Some of these effects from obesity during pregnancy include labor and delivery problems, gestational diabetes, preeclampsia, a high risk of premature birth, birth defects, and fetal or neonatal death.

Also "bacteria are passed from mother to child through the birth canal, as well as through breast milk, and research indicates that early nutrition may influence the risk of obesity later in life," Laitinen added. "There is growing evidence that this approach might open a new angle on the fight against obesity, either through prevention or treatment."

Source: ECO 2009 - The 17th European Congress on Obesity Amsterdam 6-9 May 2009 news release http://www.easo.org/eco2009/documents/Probioticsrelease_000.pdf