Can probiotics treat obesity and diabetes?

What are probiotics?

Probiotics are good (beneficial) bacteria that you can consume to balance out the bad (unbeneficial) bacteria in your gut. This natural balance of good and bad bacteria plays a huge role in your overall health - and scientists have discovered an important link between good bacteria, obesity, and diabetes.

With the help of Dr Sharmela Devi, we explore the latest emerging evidence for probiotics as a treatment for both obesity and diabetes, two conditions that are often closely related.

Can probiotics treat obesity?

Probiotics may help people with obesity to lose weight and reduce associated health problems. Dr Sharmela Devi, a dietitian nutritionist at MACS Clinic, explains:

"People who are obese have different gut bacteria to people who are not obese¹. This can lead to inflammation, which is a common complication of obesity."

Having long-term inflammation damages cells and can cause all sorts of serious problems, including type 2 diabetes, cardiovascular disease, and breast or colon cancer².

The inflammation can partly be helped by taking probiotics and making other changes to your diet. Probiotics may also help you to reverse obesity and reach a healthy weight with other lifestyle measures. According to Dr Devi, they may work in several ways:

Probiotics may prevent liver fat build-up

Fat is normally stored in the liver, and too much can raise cholesterol. However, probiotics have been shown to stop fat accumulating here, decrease liver weight and blood fats³.

Dr Devi says: "This is important because a buildup of fat in the liver can lead to non-alcoholic fatty liver disease (NAFLD), a common complication of obesity that can lead to serious liver disease, stroke, and heart attacks."

Probiotics may help weight loss

By helping to reduce liver weight, probiotics can also reduce your overall body weight and fat volume³, when supporting a healthy diet.

In one study of obese women who had food addiction, those who took probiotic supplements achieved significantly more weight loss than those who didn't. Both groups also followed a calorie-restricted diet at the same time. The study also found that these probiotics were able to regulate the hormones responsible for feeling full⁴.

Probiotics may lower cholesterol

"Studies have also shown that probiotics can help reduce cholesterol levels," says Dr Devi. One study revealed that certain probiotic strains absorb cholesterol into their cells, effectively removing it from the bloodstream⁵.

Obesity is closely linked to having high cholesterol - although there are other causes of high cholesterol, including genetics. This can cause a buildup of plaque in your blood vessels, which restricts blood flow to your heart. This is why having high cholesterol puts you in danger of heart attacks, heart disease, and stroke.

Patient picks for Healthy eating

5 easy vegan swaps for Veganuary 2024

Can probiotics help manage diabetes?

Obesity and type 2 diabetes are closely connected, the former increasing your chances of developing the latter. They also share many of the same health risks, including high blood pressure, heart disease, and other heart-related problems.

Probiotics are already being used to treat type 2 diabetes, especially the bacteria strains called Lactobacillus and Bifidobacterium. Here's why:

Probiotics improve insulin sensitivity

"Probiotics have been shown to be effective in the treatment of diabetes because they can help improve insulin sensitivity, which is important for people with diabetes," says Dr Devi.

Insulin is a hormone released by your body to help the sugar in your blood pass to your cells. By increasing your sensitivity to insulin, you can lower your blood sugar levels and the associated risks, which include damage to your eyes, nerves, and kidneys.

By reducing the buildup of fat in your liver, probiotics can reduce insulin resistance because less insulin is used up for synthesising fatty acids³.

Probiotics reduce inflammation

Dr Devi also points out that probiotics can help reduce long-term inflammation in the body, where your immune system triggers internal swelling throughout your body, leading to cell damage.

Inflammation is another common outcome of diabetes. Type 1 diabetes is more related to how your immune system works, which directly influences inflammation processes in the body. In contrast, type 2 diabetes is often related to lifestyle factors, such as having a pro-inflammatory diet or being obese, which can can trigger inflammation.

For this reason, anti-inflammatory diets are also being considered as a treatment for type 2 diabetes⁶, alongside probiotic supplementation for type 1 and type 2³.

Should you start taking probiotics?

Probiotics are found in many fermented foods, including natural yoghurt, kefir, kimchi and sauerkraut. They are also widely available as supplements, in the form of tablets, powders, and liquids - here's how to look for a quality probiotic supplement.

Dr Devi describes the evidence on probiotics for the treatment of obesity and diabetes as promising. However, she warns that there are still some knowledge gaps to be addressed.

"We don't yet know the optimal dose of probiotics you should take daily to treat obesity and diabetes," she says. "We also need more research to fully understand the long-term effects of probiotic supplements on human health."

What we do know is that consuming probiotic supplements is generally considered safe for weeks and months at a time.

Further reading

1. Moseti et al: Molecular regulation of adipogenesis and potential anti-adipogenic bioactive molecules.

2. Christ et al: Western diet and the immune system: an inflammatory connection.

3. Das et al: Current status of probiotic and related health benefits.

4. Narmaki et al: The combined effects of probiotics and restricted calorie diet on the anthropometric indices, eating behavior, and hormone levels of obese women with food addiction: a randomized clinical trial.

5. Pereira and Gibson: Cholesterol assimilation by lactic acid bacteria and bifidobacteria isolated from the human gut.

6. Tsalamandris et al: The role of inflammation in diabetes: current concepts and future perspectives.