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Are your gut bacteria making you fat?

Machen Deine Darmbakterien Dich fett?

Here is a brief summary:

  1. The bacteria in your gut affect your ability to get lean and healthy.
  2. Your digestive tract contains more than 100 types of bacteria, which together weigh about 1 kilo. They make up your gut flora and are important.
  3. Those with low microbial diversity have higher rates of obesity. They also feel worse.
  4. Studies have shown that some gut bacteria cause obesity and other gut bacteria can protect against it. "Bad" gut bacteria can cause cravings and hunger pangs that can derail your diet.
  5. Taking probiotics is not enough for most people and taking antibiotics can kill off the good gut bacteria.
  6. You can optimize your gut flora through certain foods, supplements and dietary strategies.

Intestinal bacteria: Where you get them and what they do

Bacteria begin to colonize your gut from the moment you are born. If you were born naturally, breastfed, ate raw fruit and vegetables and were allowed to play in microbial dirt, then you probably started life with a healthy, diverse gut flora. But what if you were born by caesarean section, fed formula and baby milk and grew up in the city?

Well, then you could be at a higher risk of allergies and autoimmune diseases, develop metabolic disorders and become obese. You also have a higher risk of developing diabetes and will suffer from more systemic inflammation. Fortunately, the choices you make as an adult can solve or prevent these problems.

Fat breakdown and gut bacteria

What happens when you breed mice that are completely free of bacteria and raise them in a sterile, bacteria-free environment? They benefit from a surprising advantage: they don't get fat - even if you give them food that makes ordinary mice fat: high-fat, high-fructose or high-sucrose.

Let's go one step further. Take a few bacteria from the overweight mice and give them to the bacteria-free mice. They will then also become fat - even if they are given healthy food. And as a final step, take gut bacteria from lean mice and give them to the above mice while continuing to feed them healthy food. They will become slim again. In other research, four pairs of identical human twins were found in which one twin was obese and the other twin was lean. Germ-free mice were colonized with the intestinal bacteria of these twins. The mice that were colonized with the intestinal bacteria of the lean twins remained lean.

The mice that were colonized with the intestinal bacteria of the obese twins also became obese. The resulting lean and obese mice were then kept together so that they could exchange bacteria with each other to a certain extent. After the obese mice came into contact with the lean mice with their "lean" human bacteria, these mice also became lean.

These experiments show that some bacteria can cause obesity and others can protect against obesity.

The surprising result of gastric bypass surgery

It turned out that even though the food intake is reduced by these operations, the benefits far exceed what can be observed in people who had an identical diet and had not undergone such surgery. Scientists found that the bacterial population of the digestive tract changed dramatically with gastric bypass surgery. One result of this is a cure or at least a significant improvement in type II diabetes. These changes occur before the weight loss rather than as a result of it.

Another benefit is increased energy expenditure relative to calorie intake. In the above-mentioned comparison between subjects with or without gastric bypass surgery, food intake and absorption were the same. The key difference seems to be the bacterial population of the gut.

Can antibiotics cause obesity?

On the other hand, taking antibiotics often causes obesity in previously non-obese patients. Stool samples show that taking antibiotics greatly reduces the amount of beneficial bacteria and greatly increases the amount of bacteria known to promote obesity. Furthermore, different digestive tract bacteria are associated with overweight people rather than lean people, even when diets are identical.

There are proven biochemical mechanisms for this causality. It is therefore likely that these bacteria contribute to increased body fat, impaired metabolism, insulin resistance and obesity-related inflammation when there is not a sufficient balance of beneficial bacteria.

How do these bacteria make you fat?

Scientists believe that both excessive body fat gain and body fat breakdown problems are largely a consequence of obesity-related inflammation. This inflammation results in fat cells being more prone to grow and send hormonal signals that result in impaired metabolism and reduced insulin sensitivity in muscle. One way in which this occurs is that gram-negative bacteria such as Enterobacter, Shigella, Klebsiella, Desulfovibrionaceae and Escherichia (including E. Coli) can release the endotoxin LPS, which can promote systemic inflammation and obesity. Another mechanism that may contribute to an increase in body fat is related to the fact that some gut bacteria can activate the endocannabinoid system. By doing this, they cause the host (that's you) to feel hungry, which results in the bacteria getting more food. This endocannabinoid system signaling also has negative effects on muscle cells, fat cells and insulin sensitivity. In addition, gut bacteria can increase fat storage in fat cells by suppressing FIAF (Fasting-induced Adipocyte Factor).

All of these actions contribute to advancing an individual towards obesity-related inflammation and metabolic impairment. They can also ultimately lead to obesity and/or diabetes. When the balance of bacteria in the digestive tract is unfavorable, gut bacteria have the tools necessary to effectively counteract fat loss or promote fat gain, as well as further exacerbate metabolic impairment. This is bad news for people with an unfavorable ratio of "bad" to desirable gut bacteria who are aiming for a lean, muscular body.

Gut bacteria can control you like a puppet

Metabolically unfavorable gut bacteria can cause cravings for junk food, which is the best food for them. They can make you feel bad when you deprive them of their favorite foods. This is achieved not only through the endocannabinoid system, but also through their ability to exert a strong influence on the vargus nerve and the enteric nervous system. This is not funny. The cravings and bad feelings can be powerful motivators for neglecting your diet plan or even abandoning your diet. The good news is that you can get out of their control pretty quickly by not giving in. If you consistently don't give in, the number of these bacteria will decrease, your metabolic health will improve and you'll feel better too - no cravings, no bad feelings.

I believe that one of the reasons diet plans like the Velocity Diet or the Paleo Diet work so well is because they break this cycle, which results in better metabolic health.

How can good gut bacteria help you improve your body composition?

Beneficial gut bacteria can help you improve your body composition and metabolic health by suppressing other bacteria - or rather their proliferation - that have the negative effects described above, by improving the integrity of your gut lining and by producing short-chain fatty acids. Short-chain fatty acids reduce systemic inflammation, contribute to satiety, up-regulate leptin gene expression, reduce stress-induced corticosteroid levels, improve insulin sensitivity in muscle and reduce insulin sensitivity in adipose tissue by activating FFAR2 (Free Fatty Acid Receptor 2).

How can I improve my gut flora?

There is a very strong correlation between the diversity of your gut bacteria and your metabolic health. The more types of bacteria you have in your gut, the better - at least in terms of bacteria that you have naturally ingested. So one way to improve your gut flora is to achieve a greater diversity of bacteria. Another way is to change your diet in a way that supports the function of beneficial gut bacteria and shifts the balance in favor of these bacteria.

You can also take nutritional supplements that work towards improving the balance of bacteria in your gut and/or increase the production of short-chain fatty acids.

Forget the yogurt and eat some "dirty" vegetables

As convenient as it would be to simply buy a few capsules or a bulk pack of yogurt, this won't increase the diversity of your gut bacteria very much. How many strains of bacteria are in yogurt? Maybe six? In contrast, you probably have a thousand or more types of bacteria that have colonized your gut. Six more types of bacteria would only be a minimal increase in this diversity in percentage terms.

The only way to really increase microbial diversity is the natural way, which is the way all humans have always used. Consume these bacteria through food and your environment.

As a species, we have become accustomed to being exposed to a very substantial amount of bacteria that comes from plants and dirt - and especially the dirt that our food crops grow in.

It is historically abnormal for vegetables to have been boiled, baked, fried or cleaned to a point close to complete sterilization, as is the case with commercial produce today.

By increasing your consumption of locally grown vegetables, such as those purchased at a farmer's market, most of which should be eaten raw, the variety of bacteria you are exposed to will be more in line with what humans have adapted to over the course of evolution.

Fermenting these vegetables, which you can easily do at home, can increase the value of these vegetables even further. (Commercially fermented foods often contain no beneficial bacteria at all). And don't be afraid of a little dirt from a good source. Vegetables from a farmer you trust don't need to be scrubbed to death. A light rinse will suffice. Our ancestors always had some dirt on their food and primitive peoples all over the world are not afraid to eat their food in a fairly natural state. Studies show that their gut flora is more diverse than ours.

Useful nutritional strategies

In addition to this, some dietary techniques are likely to increase the number of types of bacteria living in your gut:

Improve the quality of your carbohydrate intake

Try replacing products that contain refined wheat flour with slow-cooked oatmeal, buckwheat, sweet potatoes, parsnips, carrots, beets, pumpkin, potatoes, rye, brown rice or parboiled rice.

There are a variety of options and you will experience real benefits by changing your choices.

Eat a variety of different macronutrient compositions rather than meals that all have a fairly similar macronutrient combination

By eating some meals that are protein and fat and low in carbohydrate and others that are protein and carbohydrate and low in fat, different bacteria with different food preferences and different bile acid tolerance will all get their chance. Plan periods of no or low food intake, such as a 10 or 12 hour break between the last meal of the day and breakfast, or occasional days of reduced calorie intake.

One reason for this is that certain beneficial bacteria, unlike other bacteria, thrive during these times.

How do I feed my good bacteria?

A diet for good digestive health does not require specific macronutrient ratios. People all over the world have eaten the foods that were available to them and have been healthy. People and their gut bacteria are flexible and can be healthy on a wide range of diets. Most reasonable ratios can be fine - anything but high carbohydrate combined with high fat - if the carbohydrates are from traditional sources and the fats are not high in linoleic acid.

When it comes to better nourishing the beneficial gut bacteria, fiber from vegetables, fruits, tubers and whole grains have an excellent effect in increasing the number of these bacteria and supporting the production of short-chain fatty acids. Polyphenols, phenolic acid and anthocyanins from fruit and vegetables are also very beneficial for digestive health.

What about probiotics and fermented foods?

Many probiotic products currently available do not contain sufficient amounts of bacteria or enough different types of bacteria to make a big difference to what you already have. In addition to this, many of these products only contain bacteria that are potentially suitable for the small intestine, although the bacteria of the large intestine are also crucial. Furthermore, studies have shown that many bacteria administered in this way typically fail to colonize the gut and are no longer detectable after 3 hours.

It should also be remembered that if these are bacteria that have already colonized your gut, as you have been exposed to them before, these bacteria will already be present in your gut in a natural balance dependent on your diet. So why give more of them unless there is a need to shift this balance?

This could explain why many probiotics on the market do quite little for the average person.

However, there are exceptions. Some probiotic strains of bacteria can help with diarrhea, constipation, irritable bowel syndrome, pouchitis, urinary tract infections, Clostridium difficile infection, enteropathy and eczema. If you suffer from any of these problems, then a suitable product could help you.

If you are considering using a product to treat a condition, then you should ensure that it contains the same strain of bacteria that was used in the underlying study. If the species is the same but the bacterial strain is different, then the study is irrelevant. Unfortunately, many probiotic manufacturers cite irrelevant studies.

Prebiotics, anthocyanins and other supplements

The first category of supplements we will look at are prebiotics or fiber, which support beneficial bacteria. If you are already eating plenty of vegetables and some fruit, then there is no need to supplement with prebiotics. Your beneficial bacteria will already be getting what they need.

However, if you are eating less of these foods than humans have traditionally eaten, then supplementation makes sense. I recommend a combination of inulin and arabinogalactose in a total amount of 6 grams per serving. You can take this fiber several times a day, preferably with meals. I would like to emphasize that supplementing with prebiotics alone will generally not make a profound difference. It should be part of an overall plan. Another way is through anthocyanin supplementation. Greens and superfood blends provide plenty of polyphenols and phenolic acid, which have positive effects on the intestinal flora. If you want to use a specific polyphenol instead of a combination of extracts, quercetin is an excellent choice. Polyphenols from red wine are also very effective. Resveratrol does not have a major effect on gut bacteria, but when taken before a meal with substantial amounts of fat and calories, it blocks the pro-inflammatory TLR-4 signaling produced by some bacteria in response to such meals.

Berberine, a plant extract, also has some extraordinary properties when it comes to modulating gut bacteria. It works in part by inhibiting pro-inflammatory bacteria and shifting the balance of gut flora towards beneficial bacteria. It works so well that significant reductions in blood sugar can often be observed in people with impaired insulin sensitivity, and substantial fat loss often occurs.

Last but not least, a magnesium deficiency affects the balance of the intestinal flora. This is where a magnesium supplement or a ZMA® product can help.


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By Bill Roberts | 07/28/15

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