There has been a sharp increase in the number of people taking probiotics over the last few years following research indicating numerous health benefits.

The latest claim is that probiotics may have an effect on metabolism, leading to the suggestion that they could ?make you thin?.

The evidence

The journal Molecular Systems Biology reported that mice fed probiotic drinks had different levels of key chemicals that influence fatty acid and protein metabolism from those fed a placebo. Probiotic exposure appeared to lower blood fats and alter fat and protein metabolism. A reduction in liver glycogen (stored carbohydrate) also indicated an increase in fuel metabolism.

This was believed to be due to the way mice treated with probiotics metabolised bile acids. These acids are made by the liver and their primary function is to emulsify fats in the upper gut, potentially affecting how much fat the body absorbs. Adding ?friendly? bacteria changed the profile of bugs in the gut, increasing the number of ?good? bacteria.

Layman Lowdown

Probiotics are supplements of friendly bacteria that help the bacteria already in the colon to maintain normal digestion. Within the colon there are over 500 bacterial species. Good bacteria in the gut break down carbohydrates to create energy.

They also help the body fight infection and disease by combating the effects of bad bacteria and have been shown to offer particular benefit to those suffering from diarrhoea, some bowel diseases and irritable bowel syndrome.

These benefits, however, are not observed in all who take probiotics, and the effect on metabolism has only been observed in mice, so it is too early to jump to the conclusion that these ?friendly? bacteria could help humans lose weight.

CW says

If you choose to take probiotics, do it for the more established benefits to immune and gut health. Ideally include pre-biotic foods in your diet too, which stimulate the production of good bacteria to naturally raise levels. Sources include bananas, berries, asparagus, garlic, wheat, oatmeal, barley, tomatoes and legumes.