It sounds like something from a sci-fi film, but scientists are now recognising the strange but true connection between the bacteria living in your gut, and your weight. One study on pairs of twins where one was obese and the other wasn’t, found that the slim twin had a richer diversity of gut bacteria. Studies have also found that when gut bacteria from overweight people are put into mice, the mice gain weight.

Another study found that the ratio of two type of bacteria – prevotella and bacteroidetes – may determine how much weight you lose on a particular diet.

Ultimately it seems that we’re only just starting to realise the impact that good gut health can have on our whole bodies.

How do gut bacteria affect weight?

There are a few ways that your bacteria affect your weight.

For one thing, gut bacteria play a crucial role in how foods are digested, so a happy, healthy mixture means a smoother digestive system where you’re more likely to absorb nutrients and feel more satisfied. Gut bacteria also affect how hormones associated with feeling full, such as leptin and ghrelin, are released.

They are also connected to your mood and immune system, so a healthy gut can stop you feeling run down and reaching for comfort food.

Gut bacteria also influence how fats from food are absorbed in your intestine, which could have an impact on how your body stores fat.

How to lose weight with probiotics

Keeping your gut bacteria in tip-top health can help keep you slim, as well as easing digestive problems. Try eating a diet rich in probiotic foods which are great at introducing a wider range of bacteria, such as yoghurt, kimchi and sauerkraut. Read our extensive list of probiotic foods to try!

Stop using hand sanitiser and lose weight

You might think that liberal lashings of hand sanitiser is a great way to fight infection and stay healthy, but research has shown that applying it too frequently can kill the good bacteria living on you and actually increase your risk of illness! Being under the weather is generally rubbish for your health and fitness goals, meaning weight gain could be a problem.