Gut bacteria, or intestinal flora, are a vital part of every healthy body. There are over 100 trillion of them quietly going about their business in the dark recesses of our gut. We pay them no attention, think nothing about their wellbeing, and don’t even consider them as part of our body, just a passenger along for the ride. This is an error. Gut bacteria effect almost every aspect of our mental and physical health, and we ignore them at our peril.
What do gut bacteria do?
First off, gut flora aids in the digestive process, neutralizing many of the toxins created during digestion. Secondly, they discourage the formation of yeasts, fungi and other bad bacteria in the gut. Thirdly, they stimulate the digestive process, produce vitamins K and B for us and help absorb nutrients
So far, so good digestion.
But gut bacteria’s story goes way beyond digestion. In fact, its story has just begun as research is now being produced at an alarming rate linking gut bacteria to everything from obesity to cognitive ability.
Gut flora’s important role in our overall health has led to it being referred to as a virtual organ. Scientists are only just starting to reveal the mechanisms behind how gut flora works and its effects on homeostasis in the human body. The evidence is mounting that gut bacteria are not just a passenger in the human gut, but should be viewed in the same way we see our other organs, a body part of such vital importance that if it fails, the system fails. Studies have now linked gut bacteria to a whole host of conditions that go well beyond just the digestive system:
- Immune system (1)
- Diabetes (2)
- Heart disease (3)
- Brain development (4)
- Obesity (5)
- Irritable bowel syndrome (6)
- Inflammatory bowel disease (7)
- Brain function and morphology(8)
- Schizophrenia (10)
- Metabolism (11)
As the research rolls on, this list (which is by no means complete) will surely increase further. So maybe the question will no longer be ‘what does gut bacteria do?’ but ‘what does gut bacteria not do?’
But that’s for the scientists to figure out. In the mean time, the link between obesity and gut bacteria seems the most interesting as weight loss and dieting features in so many people’s lives. Imagine a weight loss program that had a side effect of preventing all those medical conditions? Now that’s a diet program worth its weight in gold.
Gut bacteria and weight loss
Research on how gut bacteria can help you lose weight is still in its early stages however the preliminary results are promising. It appears that gut bacteria makes some people prone to weight gain and that a person’s weight may be partially linked the composition of their gut flora. It also suggests that dieting may be pointless for these people because, unless the gut bacteria is changes, the pounds are piled back on when the diet is over.
How to change gut flora?
Studies have found that the bacteria in your gut adapt to your diet. A diet packed with saturated fat will encourage the growth of bacteria that are better evolved to deal with fat. Likewise, a diet that is unbalanced and lacking nutritional variety will promote low diversity in gut flora. (12) When it comes to gut bacteria, we are what we eat. (13)
Studies have shown that gut bacteria that thrived thanks to your unhealthy diet can take up to five times longer to move out than the period that you spent dieting. (14) Changing your gut flora doesn’t happen overnight.
Eating less and exercising more will always result in weight-loss. However, even if you lose weight, the bad bacteria, still present in your gut, will not only ‘remember’ when you were fat, but also want to take you back there. For the bacteria flourished in your obese gut and like you, is having a hard time adjusting to the new diet. Therefore, it triggers cravings, ‘forcing’ you to pick up a few more donuts and give up on the gym membership that you’re only a month into.
The problem is because of the prevalence of certain undesirable gut bacteria such as enterobacteria. The bacteria lingers in the gut throughout the diet regime and causes insulin resistance. As a result, the body finds it harder to feel satisfied after food and continues to crave fatty foods. (15)
People on such diets are restricted in how effective their weight-loss diets are because their guts are full of bacteria that deactivate the genes that switch off fat-burning. Dieting is no longer just about calorie reduction.
So how does one change gut flora when bad bacteria are still present. The answer is prebiotics and probiotics. Prebiotics are foods that contain certain fibers that good bacteria need to thrive and probiotics contain the good bacteria themselves. Any diet, if it is going to be successful in changing your gut flora naturally, needs to be heavily supplemented by both pre and probiotics.
This point cannot be emphasized enough. It’s not just an obesity diet that you need to think about, but an obesity gut bacteria diet. You should not just look to lose weight, but simultaneously change your gut flora. See here for the best probiotic foods and here for the best prebiotic foods for more dietary information.
Gut bacteria obesity treatment
If there is a link between obesity and gut bacteria composition, it logically follows that if you can change the gut bacteria, you can lose weight without having to restrict calorie intake. This gets us tantalizingly close to a gut bacteria obesity treatment and not surprisingly there is a stampede of drug companies doing research to discover just that – the ultimate fat busting pill.
The research conducted on mice shows that we may not be far away. Obese mice were switched onto a balanced diet until their weights were the same as the mice in the control group. The researchers found that found the formerly obese mice still had lingering bad gut bacteria present and as such, they quickly regained the weight when given fatty food again. However, that’s not the interesting part. When the bacteria from these obese mice was transferred into the control group mice, the control group mice also gained weight faster. Likewise, when healthy bacteria was transferred into the obese mice, they lost weight much faster.(14),(16)
If the human microbiome reacts in the same way, then it may be possible to transfer healthy gut bacteria to obese people, seeding their gut flora, and kick-starting the bodies natural ability to burn calories away for good. Indeed preliminary studies have shown just this (17). While large scale bacteria transfusions are perhaps the gut bacteria obesity treatment of tomorrow’s world, in the here and now, you will have to rely on more traditional mechanisms to maintain your gut bacteria health.
There are a number of healthy foods that if included in your diet will change the bacterial makeup of your intestines gradually and over time. Here’s a list of the best lifestyle changes to make if you want to make your gut a breeding ground for the kind of bacteria that makes you happy and helps you lose weight. A happy gut is always equal to a happy life.
How to improve your gut bacteria
1. Sweat It Out
The link between exercise and the health of the body’s organs is well established. What about gut bacteria? If you view your gut bacteria as a virtual organ, perhaps exercise can improve it as well?
Well as it happens, your gut doesn’t like it when you’re lazy. For your gut bacteria to operate at its best, you need to get regular exercise, just like all your other organs.
Studies have shown regular exercise promotes the biodiversity of your gut flora increasing the abundance of beneficial gut bacteria. (18), (19) When it comes to weight loss, exercise not only directly burns of the fat, but in promoting the well-being of your gut flora, you get a second round effect as the gut bacteria joins in the fat busting fight.
2. Load Up On Whole Foods
Whole fruits and vegetables are loaded with all the minerals and nutrients that healthy bacteria thrives on. The fiber, in particular, is the main food source that healthy bacteria prefers. Green leafy vegetables along with beans and legumes contain a lot of fiber, so stock up on them and your gut will thank you. They even inhibit the growth of undesirable bacteria.
Apples, artichokes, and blueberries, in particular, are high in fiber and contain high levels of pectin which aid in the growth of bifidobacterium and lactobacillus, two classes of bacteria that aid in weight loss. An apple a day really does keeps the doctor away! (20)
3. Sleep More
Research has shown that simply depriving yourself of sleep for two nights significantly changes the composition of gut bacteria found, with certain microbes seeing a reduction of up to 50%. (21) What’s more, the gut flora after two nights more closely resembled the flora of patients that are obese.
Lack of sleep has long been associated with obesity but the link has never been fully understood. This research clearly suggests that changes in gut flora explain the relationship.
Who’d have thought that getting a good night’s sleep may actually help you lose weight?
But it’s not a one-way street. While sleeping patterns can affect our gut flora, so too can our gut flora affect our sleep. Research also showed that certain microbes activate a protein (called TLR2) in the gut. (22) This protein helps regulate serotonin, a neurotransmitter responsible for mood, sleep, and appetite and many other psychological disorders.
So if your gut flora is out of whack through lack of sleep, there is a negative feedback loop on your general sense of well-being and mood.
Fermented foods are foods that have been altered by microbes and fall under the category of probiotics because they give your gut an influx of healthy bacteria such as lactobacilli. These probiotics seed your gut bacteria and should be the cornerstone of any diet so reduce the chance that weight is put back on when the diet is over.
Fermented foods which are great for your intestines include yogurt, sauerkraut, tempeh, kombucha, and kefir. Studies have shown that people who eat a lot of these foods have a higher level of the desirable lactobacilli and less Enterobacteriaceae bacteria which cause inflammation.
Note: Avoid flavored yogurt because it has refined sugar which healthy gut flora does not like.
5. Eliminate Processed Sugar and Processed Foods From Your Diet
Sugar and processed foods are bad for every part of your body including your gut flora. They may be good for a quick fix of energy and are convenient to find, but processed foods do nothing for your gut flora. They offer a very little variety of ingredients and they are typically sterilized of all microbes with preservatives for a longer shelf life.
Furthermore, studies run on mice have shown that such foods caused changes in their gut bacteria which led to obesity and gut disease. (23)
6. Don’t Be Afraid of The Dirt
We’ve already established that not all bacteria is bad and that includes the ones found in dirt, therefore, sterilizing everything may work against you.
A study published in the Pediatrics Journal showed that children whose parents cleaned their pacifiers by sucking them instead of boiling them were less likely to have eczema. A separate study showed that children who lived in houses with dogs had fewer allergies because the dogs, and all the bacteria that come with them, improved the diversity of the children’sir microbiomes.
The point is that sterile environments do not promote biodiversity of gut bacteria.
Clean is fine. Super clean is not.
7. Find Ways to Lower Your Stress Levels
Stress is good for you in small doses. When your body is stressed it releases natural steroids and adrenaline which give you the extra boost of power that you need to get away from that crazy guy waving a gun around.
However prolonged bouts of stress can impair you gut bacteria and research suggests that because of bacterial gut changes, your susceptibility to infection increases. (24)
Try and relax.
8. Eat More Foods that are Rich in Polyphenols
Polyphenols do many great things for your body such as reducing oxidative stress and inflammation however they are not easily absorbed by the body. Most of the polyphenols that you eat make their way all of the way to your colon where they are munched on by healthy gut bacteria. (25)
Grapes, red wine, and onions are great sources of polyphenols.
9. Breast Feeding
While breastfeeding can help new moms return to their natural weight, its true benefits are for the baby, making sure the infant has the best gut flora possible to maintain a healthy weight in later life.
When babies are born, their guts are almost sterile and bacteria-free. By the age of one, the composition of each infant’s gut bacteria is different and distinct, and by the age of 2.5 years, the gut flora will closely resemble the gut flora composition the adult will have in later life. (26),(27)
As a result, the very early years of a person’s life are critical for the healthy formation of gut bacteria for the rest of his/her life. It follows that conditions linked to unhealthy gut bacteria in adult life may actually be the result of a babies exposure (or lack thereof) to gut bacteria when born.
This is why breastfeeding is so important. For babies are quickly colonized by bacteria which allow the baby to digest its food. Indeed, babies even suppress their immune system to allow the bacteria in (28)
Much of this bacteria comes from the mother’s breast milk and skin contact, and this bacteria will form the basis of the gut bacteria for babies adult life. Likewise, the mother’s milk contains special sugars that nourish the bacteria as it becomes established.
10. Vaginal Birth
Vaginal birth does not affect a mother’s gut bacteria and is obviously not a weight loss technique. However, it gets a mention because it has long-term benefits for the infant.
Vaginal birth is very important for the establishment of gut bacteria for the infant. Secretions from the vagina are packed with bacteria that give the baby a starter kit of microbes. On the other hand, babies born by C-section tended to be colonized by bacteria that are typically found only on skin, and what’s more, this bacteria was not necessarily similar to the mothers i.e. the bacteria was picked up from the general hospital environment.
Not a comforting thought!
However, babies born by vaginal birth showed a much more balanced gut flora that closely resembled the mothers. (29) Many new c-section moms, wise to the benefits of vaginal birth, are swabbing vaginal secretions on their newborns to seed the good bacteria from birth.
11. Avoid antibiotics where possible.
Antibiotics are one the medical industry’s greatest gifts to us. Without them, countless people would die unnecessarily from easily cured diseases. However, antibiotics are not selective: they will kill all the bacteria they come into contact with including the good bacteria.
However, antibiotics are the gut equivalent of deforestation. They do not distinguish between bacteria and can leave your gut flora barren. It was widely believed until recently that gut bacteria would quickly recover back to its former glory, but this has been shown not to be the case.
In the aftermath of deforestation, you will see plant growth return, but nobody expects the trees to magically reappear. Likewise, with gut flora, many bacteria can take months to recolonise after antibiotics are administered, and in some cases, the composition of the flora is permanently changed. (30)
12. Lay Off the Red Meat and Other Animal Products
A study run by Nature showed that eating large amounts of animal products promotes the growth of bile loving bacteria which cause heart disease. Eating large amounts of animal fats forces the human body to produce higher amounts of bile which Bilophila thrive in. More bile means more biophilia and more biophilia leads to increased cases of inflammation in your gut.(32) Also, farm animals are routinely injected with antibiotics to increase yield. As mentioned, antibiotics can be devastating for your gut bacteria.
13. Avoid artificial sweeteners
Artificial sweeteners are not your usual suspect for causes of weight gain. Indeed, quite the opposite as millions of dieters reach for the sugar-free soda option.
But there is increasing evidence that artificial sweeteners have a detrimental effect on your gut bacteria. Research conducted on mice showed that sweeteners significantly altered the bacteria composition leading to the mice becoming glucose intolerant. (33) It is also thought that these changes in bacteria composition and an associated increase in bad bacteria are why weight gain was observed.
While a direct link between weight gain and sweeteners in humans has yet to be established, the damage they cause your gut bacteria is proven, and as such, they should be avoided.
- Eat fermented food
- Take a probiotic supplement
- Vary your diet as much as possible
- Exercise & sleep
- Eat artificial sweeteners
- Eat Nonorganic red meat
- Avoid antibiotics as much as possible
- Use antibacterial soap
- Eat processed foods as they are sterilized in production