We know weight loss is more than just cutting down your calories and doing a bit of exercise. Do probiotics help with weight loss as well?

Sometimes a news headline will link probiotics and obesity. What are the studies really showing us?

Gut microbes and obesity

We know that people who are obese have a different microbial balance in their gut.

Specifically, people who are overweight commonly have more microbes from the Fermicutes family, and less from the Bacterioidetes family.

These are the most common groups of microbes in the human gut. The Fermicutes group of microbes are more associated with chronic health conditions.

However, most of the evidence suggests this balance between them may be diet related.

Diet causes obesity, not the microbes. But gut microbes can increase inflammation and metabolism, which can affect weight gain.

So if you change your diet, your microbes in your digestive system will adapt.

How do microbes affect obesity

The altered make up of the gut in people who are obese can contribute to some of the negative health effects of being overweight.

Some studies in mice and rats have shown that these ‘bad bugs’ may contribute to

  • insulin resistance
  • inflammation in the intestines, which could lead to bloating or food intolerance
  • a change in the way we process fats.

Can gut microbes cause weight gain?

There are not many studies in humans, but in mice researchers have shown that implanting gut bacteria from mice who are bred to be obese into lean mice make them put on weight.

Only the microbes changed, and mice put on weight

The bacteria has a role to play in energy metabolism. Some people with more of these type of microbes may be getting more energy from their food than others who don’t have these varieties of bacteria.

This is one way in which altering the microbiome through probiotics, may help with weight loss.

Diversity is important

Some studies have shown that a reduction in the different types of microbes is associated with obesity.

When you have decreased diversity you are more likely to have a ‘leaky gut’. This means a particular toxin from bacteria (LPS or Lipopolysaccharide) can get into the body and increase inflammation.

It may be the case that it’s diet related, as if you eat a broad range of foods you’re more likely to have a diverse microbiome.

It’s possible that adding a supplement of probiotics will help with weight loss, but it’s not proven. 

Your Action Points – Optimising your gut health for weight loss

Microbes in our gut are related to the food we eat. Increasing dietary fibre and exercise has been shown to alter the composition of our gut microbes.

  • Eat more fibre – vegetables and pulses like lentils, chickpeas. The bugs especially love prebiotics (food for the bugs) like leeks, onions, garlic, artichokes. Cover half your plate in vegetables at mealtimes.
  • Increased fibre also helps us to feel fuller for longer, and potentially snack less.
  • Aim for 30 different foods a week to increase diversity of the microbes. Don’t eat the same foods every day. 
  • Drink 8 glasses of water or herb tea each day
  • Exercise – moving our body helps to create a healthy set of gut bugs and contributes to good overall health.

Hi I'm Anna Mapson, registered Nutritionist (mBANT, CNHC). I help people with IBS, SIBO, reflux and other gut health issues.

I can help you to:

  • understand your digestion better, so you recognise your triggers
  • eat a well balanced diet, with tasty meals that are simple to prepare
  • develop healthy, sustainable habits for life

“Anna is amazing! I feel totally transformed"

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