The secret ingredient that's making you put on weight

Researchers believe that emulsifiers in food could be making people put on weight and are increasing rates of conditions like diabetes, colitis and Crohn's disease.

Emulsifiers - both natural and synthetic - are used to make foods creamier and thicker as well as prolonging their shelf life. New research has found that commercial emulsifiers have a similar chemical structure to detergent that is having a negative effect on the body.

Carrying out initial tests on mice, researchers at Georgia State University found that some of these emulsifiers affected the body's balance of good bacteria and subsequently inflamed the gut - allowing the processes that lead to diabetes and weight gain to prosper.

We were thinking there was some non-genetic factor out there, some environmental factor, that would be explaining the increase in these chronic inflammatory diseases.

And we thought that emulsifiers were a good candidate because they are so ubiquitous and their use has roughly paralleled the increase in these diseases. But I guess we were surprised at how strong the effects were.

• Georgia State immunologist Andrew Gewirtz

The study, published in Nature, focused on two of these emulsifiers - polysorbate 80 and carboxymethylcellulose - additives that are most commonly found in things like ice cream, margarine, mayonnaise, creamy sauces, packaged bread and many other processed foods.

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