Supplements containing resistant starch, a type of carbohydrate that takes time to digest, helped people moderately lose weight in a small trial.
Resistant starch is naturally found in beans, whole grains, raw oats, and green bananas, and is also formed when common starchy foods like potatoes, pasta, and rice cool after cooking.
Resistant starch comes in several different forms, but what they have in common is that the structure of the molecule means that it is not easily digested and absorbed in the small intestine.
Therefore, the starch reaches further into the intestine, into the large intestine, where it is digested by bacteria. This means that starch is classified as a prebiotic.
Although some previous studies have suggested that this starch can help with weight loss, Lihuatei Researchers from the Shanghai Jiao Tong University School of Medicine in China studied its effects on gut bacteria.
Researchers asked 37 overweight people to consume sachets of starch mixed with water twice a day before meals. For eight weeks they were given resistant starch, and for a further eight weeks they were given packets containing regular starch as a comparison. Participants were also provided with three balanced meals a day and various health indicators were measured.
After consuming resistant starch for eight weeks, people lost an average of 2.8 kilograms, while regular starch had no effect on weight. Resistant starch causes less rise in blood sugar levels after meals and is considered to be good for health.
Stool samples revealed that while people consumed resistant starch, the numbers of several bacterial species increased in their intestines. When these bacteria were transplanted into mice fed a high-fat diet, they appeared to have a weight-loss effect.
Rebecca McManamon A spokesperson for the British Dietetic Association said the trial was too small to be conclusive, but the results were plausible. “These outcomes are natural,” she says.
However, some people with irritable bowel syndrome may feel bloated and uncomfortable when they eat resistant starch, as the bacteria produce gas as they break down, she says.
topic:
- carbohydrates/
- weight loss
Source: www.newscientist.com