For example, the key enzymes needed to form vitamin B12 are only found in bacteria, not in plants and animals. Sugars like table sugar and lactose milk sugar are quickly absorbed in the upper part of the small intestine, but more complex carbohydrates like starches and fibers are not as easily digested and may travel lower to the large intestine.

There, the microbiota help to break down these compounds with their digestive enzymes. The fermentation of indigestible fibers causes the production of short chain fatty acids SCFA that can be used by the body as a nutrient source but also play an important role in muscle function and possibly the prevention of chronic diseases, including certain cancers and bowel disorders.

The microbiota of a healthy person will also provide protection from pathogenic organisms that enter the body such as through drinking or eating contaminated water or food. Large families of bacteria found in the human gut include Prevotella , Ruminococcus , Bacteroides , and Firmicutes.

If microbiota are so vital to our health, how can we ensure that we have enough or the right types? You may be familiar with probiotics or perhaps already using them. These are either foods that naturally contain microbiota, or supplement pills that contain live active bacteria—advertised to promote digestive health.

Whether you believe the health claims or think they are yet another snake oil scam, they make up a multi-billion dollar industry that is evolving in tandem with quickly emerging research. Allan Walker, Professor of Nutrition at the Harvard Chan School of Public Health and Harvard Medical School, believes that although published research is conflicting, there are specific situations where probiotic supplements may be helpful.

Because probiotics fall under the category of supplements and not food, they are not regulated by the Food and Drug Administration in the U.

This means that unless the supplement company voluntarily discloses information on quality, such as carrying the USP U. Pharmacopeial Convention seal that provides standards for quality and purity, a probiotic pill may not contain the amounts listed on the label or even guarantee that the bacteria are alive and active at the time of use.

In addition to family genes, environment, and medication use, diet plays a large role in determining what kinds of microbiota live in the colon. A high-fiber diet in particular affects the type and amount of microbiota in the intestines.

Dietary fiber can only be broken down and fermented by enzymes from microbiota living in the colon. Short chain fatty acids SCFA are released as a result of fermentation.

This lowers the pH of the colon, which in turn determines the type of microbiota present that would survive in this acidic environment. The lower pH limits the growth of some harmful bacteria like Clostridium difficile. Growing research on SCFA explores their wide-ranging effects on health, including stimulating immune cell activity and maintaining normal blood levels of glucose and cholesterol.

Foods that support increased levels of SCFA are indigestible carbohydrates and fibers such as inulin, resistant starches , gums, pectins, and fructooligosaccharides.

These fibers are sometimes called prebiotics because they feed our beneficial microbiota. Although there are supplements containing prebiotic fibers, there are many healthful foods naturally containing prebiotics.

The highest amounts are found in raw versions of the following: garlic, onions, leeks, asparagus, Jerusalem artichokes, dandelion greens, bananas, and seaweed.

In general, fruits , vegetables , beans , and whole grains like wheat, oats, and barley are all good sources of prebiotic fibers. Be aware that a high intake of prebiotic foods, especially if introduced suddenly, can increase gas production flatulence and bloating.

Individuals with gastrointestinal sensitivities such as irritable bowel syndrome should introduce these foods in small amounts to first assess tolerance. With continued use, tolerance may improve with fewer side effects. If one does not have food sensitivities, it is important to gradually implement a high-fiber diet because a low-fiber diet may not only reduce the amount of beneficial microbiota, but increase the growth of pathogenic bacteria that thrive in a lower acidic environment.

These include fermented foods like kefir, yogurt with live active cultures, pickled vegetables, tempeh, kombucha tea, kimchi, miso, and sauerkraut.

The microbiome is a living dynamic environment where the relative abundance of species may fluctuate daily, weekly, and monthly depending on diet, medication, exercise, and a host of other environmental exposures.

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Future areas of research What is the microbiome? The gut microbiome teaches the immune system the difference between friend and foe, making it an integral part of how well immunity functions.

This interwoven relationship and constant communication between the gut microbiome and the immune system is the primary reason researchers search for cures to all sorts of illnesses by focusing on the gut. This process has been implicated in:.

This list is far from exhaustive. You can dive deeper into which diseases are linked to gut dysbiosis here. The gut microbiome acts as a conductor for the symphony, making sure everything plays in tune and on time. When your gut microbiome is out of harmony, it can throw off your hormones and cause a variety of health issues ranging from weight gain to thyroid dysfunction.

How Your Gut Microbiome Affects Your Mental Health. The gut-brain connection is constant and even has its designated line of communication—the vagus nerve. Changes in the gut microbiome are linked to the mind on many levels including: [14,15].

The gut-brain connection is so strong that one of the fastest growing areas of neuroscience looks at the gut first. Beauty truly comes from the inside out. The gut microbiome plays a direct role in the appearance of your skin through influencing:. When it comes to autoimmune skin conditions such as eczema, rosacea, and psoriasis, the gut is known to be a major driver behind the worsening of these conditions.

You can read more about that here. Could the gut microbiome be a predictor of heart disease? Researchers from the University of Cambridge seem to think so. They found that specific metabolites, such as trimethylamine N-oxide TMAO , could be a good indicator of heart disease risk.

High levels of TMAO in the body occur when bacteria convert choline into trimethylamine TMA , which is then absorbed by the body and converted to the harmful version, TMAO. Choline one of the B-complex vitamins is found in many animal products and legumes, which might make you want to cut back on these foods.

However, the initial part of this conversion — from choline to TMA — only occurs when you have certain bacteria in your microbiome. Viome is on a mission to make chronic illness optional through promoting personalized gut microbiome health.

Everyone knows someone diagnosed with a chronic illness, diabetes, or an autoimmune disease. Moreover, we know that once treatment begins, it can often be too late. We are the only company currently capable of running this functional microbiome analysis. Our proprietary technology not only identifies the strains of organisms present in your gut but more importantly, reveals what they produce in the body.

This technology gives you the power to take action now and keep you on the road to good health. Viome is providing this educational information to share the exciting developments being reported in the scientific literature about the human microbiome and your health. Viome products are not intended to diagnose, treat, or prevent any disease.

Race to 2 Million: Join Us In the Battle Against Chronic Diseases. Why Scientists Are Searching the Gut for Cures to All Chronic Diseases.

However, probiotics may help lower cholesterol and the risk of heart disease. The gut microbiome also may help control blood sugar, which could affect the risk of type 1 and 2 diabetes. One recent study examined 33 infants who had a genetically high risk of developing type 1 diabetes.

It found that the diversity of the microbiome dropped suddenly before the onset of type 1 diabetes. It also found that levels of a number of unhealthy bacterial species increased just before the onset of type 1 diabetes Another study found that even when people ate the exact same foods, their blood sugar could vary greatly.

This may be due to the types of bacteria in their guts The gut microbiome plays a role in controlling blood sugar and may also affect the onset of type 1 diabetes in children. First, certain species of bacteria can help produce chemicals in the brain called neurotransmitters. Therefore, the gut microbiome may also affect brain health by helping control the messages that are sent to the brain through these nerves 42 , A number of studies have shown that people with various psychological disorders have different species of bacteria in their guts, compared to healthy people.

This suggests that the gut microbiome may affect brain health 44 , A small number of studies have also shown that certain probiotics can improve symptoms of depression and other mental health disorders 46 , The gut microbiome may affect brain health by producing brain chemicals and communicating with nerves that connect to the brain.

There are many ways to improve your gut microbiome , including:. Eating a wide variety of high-fiber and fermented foods supports a healthy microbiome.

Taking probiotics and limiting antibiotics can also be beneficial. The gut microbiome plays a very important role in your health by helping control digestion and benefiting your immune system and many other aspects of health.

An imbalance of unhealthy and healthy microbes in the intestines may contribute to weight gain, high blood sugar, high cholesterol and other disorders. To help support the growth of healthy microbes in your gut, eat a wide variety of fruits, vegetables, whole grains and fermented foods. Our experts continually monitor the health and wellness space, and we update our articles when new information becomes available.

Your gut bacteria play several important roles in your health. Here's how your gut bacteria can influence your weight.

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A twisted stomach can happen after a gastric sleeve for several reasons, including…. Specific bacterial species can prevent or promote inflammation and play a significant role in supporting overall health.

When pathobiontic bacteria become too abundant from antibiotics and medications, poor diet, and illness, they create an inflammatory-rich environment that triggers proinflammatory cytokines. Ongoing studies show other metabolic disorders like obesity, fatty liver disease, hypertension, kidney disease, depression, anxiety, and neurodegenerative diseases are linked to an abundance of proinflammatory cytokines.

When inflammation is persistent, it can damage the lining of the gut, which creates increased intestinal permeability, also known as leaky gut syndrome.

Toxins and normally healthy undigested food particles enter the bloodstream through the open junctions, which may trigger an autoimmune response and lead to further inflammation.

According to research, the leakage can cause various health issues, including bloating and gas, cramps, fatigue, skin rashes, food allergies, sensitivities, and headaches. Other more severe conditions include autoimmune conditions , mood disorders and depression, Type 1 diabetes , Type 2 diabetes , IBD, and degenerative diseases like multiple sclerosis.

Researchers are studying the possibility that many non-gastrointestinal related disorders may be associated with or exacerbated by leaky gut , including the following conditions:.

Non-alcoholic fatty liver disease NAFLD ,. Central nervous system injury. Another issue related to gut health and chronic illness is brain health.

At our clinic, we frequently find that our patients experience gastrointestinal issues, brain fog, confusion, and frequent headaches as a symptom of their complex chronic illness.

This is because the brain and gut are intimately connected through the gut-brain axis. Here is a scenario of how this may occur:.

When our patients are treated for intestinal permeability or leaky gut, we use various treatments to heal the open junctions.

When the gut is damaged, it interferes with nutrient and medication absorption, so most of our patients have regular Infusion-therapy sessions. Other important aspects of healing the intestinal lining include dietary supplements, such as prebiotics and probiotics.

Our physicians choose a symbiotic approach so that the prebiotics feed the probiotics to help restore the microbiota to a balanced state. An individual may need more specific vitamins and minerals because the body has not been absorbing adequate levels of nutrients. Nutrition is always an essential aspect of care.

Our patients work with their physicians to establish healthy eating habits abundant with polyphenols, fibers, and fermented foods that help heal the gut.

We also emphasize stress management and mind-body techniques to heal the gut and the brain. Some people may also have to avoid certain antagonizing foods because of food sensitivities and allergies that develop from inflammation and gut permeability issues. These microbes:. We once thought these polysaccharides, oligosaccharides, and other carbohydrates were completely indigestible.

But it turns out our microbes break these down and ferment them into beneficial short-chain fatty acids such as butyrate, propionate, and acetate. Short-chain fatty acids help protect against obesity, insulin resistance, and are anti-inflammatory.

Our microbes also heavily regulate how much energy we can extract, store, and use from our food. So much so, that scientists believe our weight may have much more to do with what microorganisms are in our guts than how much we eat. You can read more about how your microbes affect your digestion and shape your body here.

How Your Gut Microbiome Affects Your Immune System. The gut microbiome teaches the immune system the difference between friend and foe, making it an integral part of how well immunity functions. This interwoven relationship and constant communication between the gut microbiome and the immune system is the primary reason researchers search for cures to all sorts of illnesses by focusing on the gut.

This process has been implicated in:. This list is far from exhaustive. You can dive deeper into which diseases are linked to gut dysbiosis here. The gut microbiome acts as a conductor for the symphony, making sure everything plays in tune and on time. When your gut microbiome is out of harmony, it can throw off your hormones and cause a variety of health issues ranging from weight gain to thyroid dysfunction.

How Your Gut Microbiome Affects Your Mental Health. The gut-brain connection is constant and even has its designated line of communication—the vagus nerve. Changes in the gut microbiome are linked to the mind on many levels including: [14,15]. The gut-brain connection is so strong that one of the fastest growing areas of neuroscience looks at the gut first.

Beauty truly comes from the inside out. The gut microbiome plays a direct role in the appearance of your skin through influencing:.

For the microbiome to flourish, the right balance must exist, with the healthy species dominating the less healthy. Scientists do not fully understand how the microbiome factors into the risk of developing chronic diseases, such as heart disease, obesity, and type 2 diabetes.

Many factors, including differences between individuals and individual diets, have made this a difficult area to investigate. But a new study , published in Nature Medicine , accounts for these factors and sheds light on how our diets shape our microbiome and how our microbiome, in turn, influences our disease risk.

The researchers studied more than 1, individuals enrolled in PREDICT 1, a large trial looking at individual responses to food. They also collected detailed, long-term dietary intake information from all of these individuals, so they could analyze their dietary patterns, including their intake of different food groups, foods, and nutrients.

In addition, they collected information from the study participants on a variety of factors that are known to influence metabolism and disease risk, including pre- and post-meal measures of blood sugar glucose , cholesterol, and inflammation.

Finally, they measured personal health attributes of the study participants, including age, weight, body mass index BMI , body fat, and blood pressure. The study found that the health of the microbiome is influenced by diet, and that the composition of the microbiome influences the risk of health outcomes.

The results showed that specific gut microbes were associated with specific nutrients, foods, food groups, and overall diet composition. Health conditions such as heart disease, type 2 diabetes, obesity, and general inflammation appeared to be most impacted by diet-influenced changes to the microbiome.

For example, less healthy dietary patterns dairy desserts, unhealthy meats, processed foods supported gut species that were associated with measures of blood sugar, cholesterol, and inflammation that are significantly associated with higher risk of cardiac events, strokes, and type 2 diabetes.

In contrast, a more diverse gut microbiome was tied to healthy dietary patterns high-fiber vegetables like spinach and broccoli, nuts, and, heathy animal foods such as fish and eggs and was linked to measurements tied to lower risk of certain chronic diseases.

In addition, the study found that polyunsaturated fats found in fish, walnuts, pumpkin, flax and chia seeds, sunflower, safflower, and unhydrogenated soybean oils produce healthy gut species linked to a reduced risk of chronic disease.

So what do these findings mean for us? First, the study showed that eating more unprocessed plant foods — fruits, vegetables, nuts, seeds, and whole grains — allows the gut microbiome to thrive.

Some animal foods, such as fish and eggs, are also favorable. Avoiding certain animal foods, such as red meat and bacon, dairy foods, and highly processed foods even processed plant foods such as sauces, baked beans, juices, or sugar-sweetened drinks and desserts prevents less-healthy gut species from colonizing the gut.

It is important to note that food quality matters; processed or ultra-processed plant-based foods were not associated with heathy clusters of gut microbes. When choosing foods, consider whether they are processed or unprocessed, in addition to whether they are a plant or animal food.

It can also be helpful to think in terms of dietary patterns, rather than individual foods or food groups. Meal patterns that emphasize foods beneficial to the microbiome are the whole-food, plant-based dietary patterns.

These include vegan no animal products and ovo-vegetarian vegetarian plus eggs diets. The pescatarian eating pattern, in which oily and white fish are the meats of choice, is also good for the microbiome. Emphasizing minimally processed plant foods allows the gut microbiome to thrive, providing protection against, or decreasing the risk of, chronic diseases such as heart disease, diabetes, metabolic disease, and obesity.

Sue-Ellen Anderson-Haynes, MS, RDN, CDCES, LDN, NASM-CPT , Contributor. As a service to our readers, Harvard Health Publishing provides access to our library of archived content. Please note the date of last review or update on all articles. No content on this site, regardless of date, should ever be used as a substitute for direct medical advice from your doctor or other qualified clinician.

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Get helpful tips and guidance for everything from fighting inflammation to finding the best diets for weight loss Not only are these microbes critical to our survival, but they also influence everything from shaping our body to affecting our mood.

As Martin J. Every one of us is covered in microbes with the gut being the richest source. The microorganisms in and on our bodies weigh between two to six pounds, making them heavier than the brain.

We each have multiple microbiomes in our eyes, mouth, nose, skin, and if you are a female, also in the vagina. During the first seven years of your life, what you eat and what you come in contact with continues to develop your microbiome. These microbes:.

We once thought these polysaccharides, oligosaccharides, and other carbohydrates were completely indigestible. But it turns out our microbes break these down and ferment them into beneficial short-chain fatty acids such as butyrate, propionate, and acetate. Short-chain fatty acids help protect against obesity, insulin resistance, and are anti-inflammatory.

Our microbes also heavily regulate how much energy we can extract, store, and use from our food. So much so, that scientists believe our weight may have much more to do with what microorganisms are in our guts than how much we eat.

You can read more about how your microbes affect your digestion and shape your body here. How Your Gut Microbiome Affects Your Immune System. The gut microbiome teaches the immune system the difference between friend and foe, making it an integral part of how well immunity functions.

This interwoven relationship and constant communication between the gut microbiome and the immune system is the primary reason researchers search for cures to all sorts of illnesses by focusing on the gut. This process has been implicated in:.

This list is far from exhaustive. You can dive deeper into which diseases are linked to gut dysbiosis here. The gut microbiome acts as a conductor for the symphony, making sure everything plays in tune and on time. When your gut microbiome is out of harmony, it can throw off your hormones and cause a variety of health issues ranging from weight gain to thyroid dysfunction.

How Your Gut Microbiome Affects Your Mental Health. The gut-brain connection is constant and even has its designated line of communication—the vagus nerve.

Changes in the gut microbiome are linked to the mind on many levels including: [14,15]. The gut-brain connection is so strong that one of the fastest growing areas of neuroscience looks at the gut first.

Beauty truly comes from the inside out. The gut microbiome plays a direct role in the appearance of your skin through influencing:. When it comes to autoimmune skin conditions such as eczema, rosacea, and psoriasis, the gut is known to be a major driver behind the worsening of these conditions.

You can read more about that here. Could the gut microbiome be a predictor of heart disease? Researchers from the University of Cambridge seem to think so.