What are probiotics? Simple, they are live microorganisms that have health benefits when eaten. They can be found in both supplements and fermented foods.
Bacteria in the gut affect weight regulation.
Our digestive system is a universe of myriad microorganisms that when in balance, maintains our gut’s health.
The majority of these are bacteria, most of which are friendly. Friendly bacteria produce several important nutrients, including vitamin K and certain B-vitamins. They also help break down fiber that the body can’t digest, turning it into beneficial short-chain fatty acids like butyrate.
There are two main families of good bacteria in the gut: bacteroidetes and firmicutes. And studies show that body weight seems be related to the balance of these two families of bacteria.
In those studies, people with obesity had more firmicutes and fewer bacteroidetes, compared to normal-weight people.
All of these studies suggest that gut bacteria may play a powerful role in weight regulation.
How Can Probiotics Affect Changes in Weight?
Certain probiotics can make you harvest fewer calories from the foods you eat. Studies show they inhibit the absorption of dietary fat, increasing the amount of fat excreted with feces.
Certain bacteria, such as those from the Lactobacillus family, have been found to function in this way.
Probiotics may also fight obesity in other ways:
- Release of GLP-1: Probiotics may help release the satiety (appetite-reducing) hormone GLP-1. Increased levels of this hormone may help you burn calories and fat (Source 1, Source 2).
- Increase of ANGPTL4: Probiotics may increase levels of the protein ANGPTL4. This may lead to decreased fat storage (Source 1).
There is also a lot of evidence that obesity is linked to inflammation in the brain. By Improving gut health, probiotics may reduce systemic inflammation and protect against obesity and other diseases.
Probiotics May Help You Lose Weight and Belly Fat
This a good news for you, I know. Studies have found that certain strains of the Lactobacillus family can help you lose weight and belly fat.
According to a longitudinal study, eating yogurt with Lactobacillus fermentum or Lactobacillus amylovorus reduced body fat by 3–4% over a 6-week period.
Also on another study of 125 overweight dieters investigated the effects of Lactobacillus rhamnosus supplements on weight loss and weight maintenance.
During a 3-month study period, the women taking the probiotics lost 50% more weight compared to the group taking a dummy pill (placebo). They also continued to lose weight during the weight maintenance phase of the study.
More interestingly, a wide literature on probiotics that have been documented and studied over time suggest that of all the probiotic bacteria studied to date, Lactobacillus gasseri shows the most promising effects on weight loss. Also, even numerous studies in rodents have found that it has anti-obesity effects.
One study followed 210 people with a lot of belly fat. It found that taking Lactobacillus gasseri for 12 weeks reduced body weight, fat around organs, BMI, waist size and hip circumference.
What’s more, belly fat was reduced by 8.5%. However, when participants stopped taking the probiotic, they gained back all of the belly fat within a month.
So, to top it all and sum it up, some strains of the Lactobacillus family have been shown to reduce weight and belly fat. Lactobacillus gasseri appears to be the most effective.
There are probiotics that may prevent weight gain.
An ounce of prevention is better than a pound of cure, so goes the old maxim. This is certainly true for human weight. Losing weight is not the only way to fight obesity. It is in fact the last battle. Prevention is even more important, as in preventing the weight from accumulating in the first place.
In one 4-week study, taking a probiotic formulation called VSL#3 reduced weight gain and fat gain on a diet where people were overfed by 1000 calories per day.
On this graph, you can see how the probiotic group gained significantly less fat:
This indicates that some probiotic strains might be effective at preventing weight gain in the context of a high-calorie diet. However, this needs to be studied a lot more.
Remember this, certain probiotic strains may be able to prevent weight gain on a high-calorie diet.
But there are also probiotic strains that may increase the risk of weight gain and obesity.
But but but… not all studies have found that probiotics help with weight loss. There are studies that suggest that certain probiotic strains might lead to weight gain, not loss. This includes Lactobacillus acidophilus. Remember that bitch, Lactobacillus acidophilus.
One recent study reviewed 4 controlled clinical trials. It concluded that probiotics did not reduce body weight, BMI or body fat levels in overweight or obese adults.
Probiotics are just a part of a big puzzle.
Probiotics offer a wide range of health benefits. However, their effects on weight are mixed, and seem to depend on the type of probiotic. It’s not a one-size-fits all thing. And as we keep reminding everyone: In nutrition, everything is rarely black and white.
Evidence indicates that Lactobacillus gasseri may help people with obesity lose weight and belly fat. Additionally, a blend of probiotics called VSL#3 may reduce weight gain on a high-calorie diet.
At the end of the day, certain types of probiotics may have modest effects on your weight, especially when combined with a healthy, real food-based diet.
However, there are many other reasons to take a probiotic supplement besides weight loss.
They can improve digestive health, reduce inflammation, improve cardiovascular risk factors and even help fight depression and anxiety.