A little fibre a day can help pounds fly away for overweight kids, Calgary study suggests

Overweight children who took a daily prebiotic fibre supplement shed body fat while those given a placebo kept gaining weight almost three times faster than the average kid, a Calgary study has found.

The findings could point to a simple and inexpensive new tool in the fight against childhood obesity, according to the study by nutritional biochemist Raylene Reimer and her team at the University of Calgary.

Their paper was published this month in Gastroenterology, the journal of the American Gastroenterology Association (AGA).

The children, who were classified as overweight or obese but otherwise healthy, were randomly assigned to groups given either the prebiotic fiber — oligofructose-enriched inulin — or a placebo once daily for 16 weeks.

Prebiotics are found naturally in garlic, onions, bananas and whole wheat and act as a fertilizer for the good bacteria in the gut, said a U of C release. They differ from probiotics, which are live bacteria found in a variety of foods, including yogurt and sauerkraut.

After taking the prebiotic supplement for four months, the children in the study — who ranged from seven to 12 years old — lost body fat, including fat around their abdomen, which increases the risk for developing Type 2 diabetes and heart disease, according to the the U of C.

Children who took the prebiotic fibre supplement for 16 weeks obtained an almost normal rate of weight gain, similar to what would be observed in a healthy, growing child. (Riley Brandt/University of Calgary)

Children who were given a placebo continued to gain weight almost three times faster than they should have for a child of their age and gender.

The supplement consisted of a couple teaspoons of powdered fibre, mixed in a water bottle, taken once per day.

“In this study we really nicely showed that this prebiotic normalized their rate of growth,” said Reimer, a professor in the kinesiology department and the department of biochemistry and molecular biology at the Cumming School of Medicine.

“And of course they are kids. They need to be growing. They need to be gaining weight, and this study showed [a] prebiotic could do that.”

The researchers used a fibre mixture not sold commercially. However, they told the participants’ families that Benefibre, available at grocery and drug stores, is very similar. 

Overweight kids’ growth slowed to ‘almost normal’

The study also concluded that the fibre decreased the amount of triglycerides — a type of fat that plays a role in heart disease — in participants’ blood by 19 per cent.

The annual projected increase per year in body weight for the children taking the supplement would be three kilograms versus eight kilograms for those who got the placebo, the researchers concluded.

“The children who took the fibre obtained an almost normal rate of growth. The same you would see in a healthy child,” Reimer said.

“This isn’t like going and having a surgery where you’re to lose 50 to 100 pounds. It’s a diet ingredient. It’s not a medication, but it’s something that’s very safe, very easy to do.”  

The researchers designed the study as a double-blind, placebo-controlled trial with 42 participants.

Reimer says the other exciting discovery to emerge from the research was that the children who took the supplement developed a healthier mixture of gut bacteria.

‘Promising’ evidence 

Dr. Geoffrey A. Preidis, a member of the AGA Center for Gut Microbiome Research and Education scientific advisory board, says the study was well-designed and demonstrates that prebiotic supplements could help combat childhood obesity, a costly and prevalent problem.

“It is promising to see this evidence that alteration of the gut microbiota can be used to restore health. As a clinician, I hope that continued research into prebiotics will lead to a new strategy for the treatment of obesity.”

The study was supported by grants from the BMO Financial Group Endowed Research Fund in Healthy Living, Alberta Children’s Hospital Foundation, Alberta Children’s Hospital Research Institute and the Canadian Institutes of Health Research.