Gut bacteria fat

Are Your Gut Bacteria Keeping You Fat?

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Being overweight or obese is a growing problem in the world. Over 50% of the world population is overweight of which 25% is obese. In obesity, the risk of developing diabetes, cardiovascular disease, and other diseases is greatly increased. Therefore it is no surprise that many people want to do something about that!
In my practice as a dietitian, it is more and more common that people do not manage to lose weight. Regardless of the effort they put into it. Could there be an underlying cause for this? Are your gut bacteria keeping you fat?

Gut bacteria overweight

Research on Gut Bacteria

In recent years there has been an increasing amount of research into the relationship of being overweight and your gut health. In the intestine, the food is digested, absorbed and, if it is not usable, excreted with the feces. However, the food that we can not digest is processed by our intestinal bacteria before it is being excreted. This is the nutrition that our gut bacteria thrive on, through which they survive and grow. They create vitamins, gas, and acids that are very valuable to us and protect us against the growth of bad bacteria. This is how we live together with our intestinal bacteria, and you could even say that we are dependent on each other. But what if those bacteria are not happy with us? Or if the good bacteria are taken over by bad ones?

Gut bacteria fat

The Role of Gut Bacteria on Your Weight

Humans have one hundred trillion (or 1014) bacteria in their intestines. Almost everyone has the same basic groups of bacteria. But the quantity and composition of these bacteria and the additional bacterial colonies in the gut vary greatly between individuals. This depends, among other things, on the diet, medicine use, weight and general health of the person. In general, overweight people have fewer types of bacteria in comparison to people with a healthy body weight.  Having a large variety of bacteria has many benefits, they help maintain a healthy metabolism by playing an active role in the processing of fat and sugars. They, therefore, have a big influence on energy balance and storage.

There are strong signs that the gut bacteria that occur in overweight people have an increased ability to get energy from the diet, disrupt the immune system and promote inflammation. This means that, if an overweight person eats the same foods as someone with a healthy weight, the overweight person will absorb more calories, thus storing the surplus calories as fat.

Are you having problems maintaining your weight? Do you want to improve your gut health and start losing weight? I can help!
Schedule a free symptom assessment and I’ll show you how.

How to Improve Your Gut Bacteria Through Nutrition

Changes in your diet affect your gut and bacterial colonies within a few days. The bacteria in your gut need nutrition. If you feed the good bacteria the healthy food they need, they will grow, thrive and help you. If you do not feed the bad bacteria the food they need, they will starve … And that’s exactly what you want!

The colonization of the intestinal bacteria starts at birth. For example, a child that is born with cesarean has a less diverse bacterial composition than one who had a vaginal birth. It even seems that children who are born with a cesarean are 40% more likely to become overweight later in life. Unfortunately, that is nothing not something you can still change when you’re an adult, but there are certainly possibilities to help you!

Curious about ways to improve your microbiome and your health? Schedule a free symptom assessment with the Positive Gut dietitian.

As I said earlier, in adults it seems that overweight people have a reduced diversity of intestinal bacteria compared to adults with a healthy weight. By losing weight, the diversity of the bacteria increases. But what kind of changes can you make in your diet to increase the different types of bacteria?


The bacteria in the gut need energy. They create this from fiber. By eating enough fiber, the bacteria have an excellent nutrient source to produce short-chain fatty acids (SFCA) like butyrate. These short-chain fatty acids help keep the intestinal wall healthy and ensure a good sugar and energy metabolism. The short-chain fatty acid butyrate can even help to suppress appetite and stimulate the growth of brown fat (which does not store fat but creates heat).

Which Foods Contain Fiber?

fiber gut bacteria

There are 3 different types of fiber that you can find in foods. Soluble fiber, insoluble fiber, and resistant starch. Each one of these fibers is an excellent source of nutrition for your healthy bacteria.

Soluble fibers from: fruit, vegetables, and legumes. This fiber binds fluid in the intestine without increasing the amount of stool.

Insoluble fibers from: grain products. This fiber increases the volume of the stool and it retains moisture.

Resistant starch: This is a type of fiber that occurs naturally in products, but also forms when you cool down cooked starch products like potato, rice, and pasta. Want to read on about resistant starch? Click this link to do so.

Fiber-Rich Foods

-Vegetables; raw, baked or boiled
– Fruit
– Legumes, like white and brown beans, lentils and chickpeas 
– Dried fruits like plums, raisins, figs, dates, and apricots 
– Whole grain products like rye, oats, whole grain bread, crackers or knäckebröd, muesli
– (Cooled down) potatoes, brown rice, wholemeal macaroni and spaghetti
– Nuts, peanuts, sesame seeds, linseed, pumpkin seeds, sunflower seeds, chia seed

Eliminate Sweeteners

eliminate sweeteners gut

Recent studies have shown that the regular use of sweeteners (eg. acesulfame-K, sucralose, aspartame, saccharin) can decrease the diversity of intestinal bacteria. This makes light products very detrimental to the intestines and your body weight. They should, therefore, better be replaced by a healthy non-light product. But do not swap them for the sugar-rich products. This is a breeding ground for your bad bacteria!

Use Polyphenols and Antioxidants

Polyphenols and antioxidants gut

The use of polyphenols can increase the diversity of intestinal bacteria and the production of short-chain fatty acids. Polyphenols are substances with anti-inflammatory properties and are found in tea, coffee, berries and vegetables such as artichokes, olives, and asparagus.

Antioxidants in the diet can easily be recognized by color. The more color a natural product has, the more antioxidants it contains.

Use Probiotics

Probiotics gut bacteria

Most people know probiotics (good bacteria) as a sour milk drink or supplement. However, this is not a great way to obtain healthy intestinal bacteria. Through proper nutrition, you can find many types of probiotics and thus support your intestines.

Good and healthy sources of probiotics are: 
– Al types of fermented foods: sauerkraut, kimchi, pickles 
– Yogurt.
– Kefir (click here to buy on Amazon)
– Kombucha

If you’re curious about Kombucha, find my recipe for kombucha here!

Looking for ways to improve your gut microbiome? Schedule a free symptom assessment and I’ll show you how!

Intermittent Fasting (IF) / Time Restricted Eating (TRE)

In mice research (so not yet proven in humans!) it appears that mice that do IF have a greater diversity in the gut microbiome after only 4 weeks of doing it.

With intermittent fasting, you fast (i.e. not eating) for at least a few days a week. Nowadays, food is always readily available and it is possible to eat several times a day or even throughout the whole day.
For the body, this is not optimal. If the body is constantly digesting food, other ‘maintenance jobs’ will be omitted.
You could compare it with cleaning the kitchen cabinets. If we are too busy, the cleaning of the kitchen cabinets will be postponed. Yet dust continues to accumulate…..

That’s also kind of how it works in the body. Once the body has finished digesting food, it is time for the other less urgent (but still important!) tasks. Also, the organs that produce all the digestive juices get a well-deserved rest during a fast. The cleaning process called ‘autophagy’ is started in a fasted state in which all cell components that function poorly are cleaned up and inflammation in the body is being reduced. Furthermore, the fat reserve is addressed for energy during intermittent fasting.

Please check out my more extensive article about TRE and IF if you want to read on!

What have you been trying to promote gut health? Let me know in a comment below!

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  1. I’ve tried the Low FODMAP, but I have a difficult bowel. I can’t seem to tolerate fibre and my intestines always feel inflamed . I’m also VEGAN and don’t know what yorstanymore. I’ve had 4 bowel ops and now suffer with adhesions. But I want to get healthy and am trying to build up my good bacteria

    1. Hey Glenda, you have been through a lot. Building up the healthy bacteria is always a good plan. Too bad the FODMAP diet hasn’t worked for you. But it’s good to keep on looking until you find your solution.

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