We wrote an earlier post about our gut microbiome, the trillions of bacterial cells that live in our large intestine. In this previous post, we talked about how an unhealthy gut microbiome impacts many health conditions. The gut microbiome is a hot research field right now and thousands of studies are being conducted and published every day around the world.
Researchers are finding that the bacteria in our gut do far more than aid in digestion — gut microbiome health may play a role in obesity, cancer, mental health, allergies, diabetes, irritable bowel disease, skin disorders, Alzheimer’s, Parkinson’s, osteoarthritis and autoimmune diseases. Every day more evidence suggests that we need to pay attention to our gut microbiome — and fend off chronic diseases and conditions by improving our gut health. Read on to learn how you can improve — or harm — your gut microbiome.
It helps to understand a little more about the gut microbiome and how what we eat and drink affects it. At least 40 trillion microorganisms such as viruses, fungi, bacteria and other living things live in our intestinesand on our skin. Called microbes, the ones that live in our gut are known as our gut microbiome. Some scientists even refer to our gut microbiome as the “forgotten organ.”
As many as 1,000 bacteria species live in the human microbiome and each plays a different role. The beneficial bacteria help digest food, produce vitamins and destroy disease-causing cells. However, some of our gut bacteria can be harmful. When our gut microbiome becomes unbalanced, meaning too many or too little of certain microbes, it can lead to a whole host of health conditions. This unbalance is known as dysbiosis.
The bacteria in our gut need food, which they get from undigested food. One of the reasons dietary fiber is so essential to our diet is because our gut bacteria use it to produce short-chain fatty acids (SCFAs). SCHFAs provide energy for the bacteria and reduce inflammation. Gut bacteria “food” is called a prebiotic. Research has found that our diet and lifestyle can have a significant impact on our gut microbiome.
It should come as no surprise that many of the foods we already know to be unhealthy also can negatively impact our gut microbiome. Foods to eat in moderation or avoid include:
Our bodies need protein, but research has found that eating a lot of animal protein, including dairy and eggs, can be bad for our gut health. We should avoid red meat in particular— research suggests that it reduces the number of short-chain fatty acids, which our bacteria need to survive. Red meat also increases the levels of a bacteria by-product called trimethylamine N-oxide, which leads to a higher risk of stroke and heart attack.
Some research suggests that diets rich in saturated and trans fats can increase the “bad” gut bacteria numbers and decrease the beneficial ones. Many foods are fried in trans fats — and foods such as butter and fatty mean contain saturated fat.
You likely already know that knocking back more than a drink or two a day is bad for your health. Turns out it may be bad for our gut microbiome. Studies of alcoholics found that the rate of dysbiosis(unbalanced bacteria) was higher than in non-alcoholics.
You may also have heard about links between artificial sweeteners and diseases such as cancer. Research in rats going back decades has found that artificial sweeteners impacted their gut microbiome. More recent studies have found a correlation between glucose intolerance and artificial sweeteners in humans because they stimulate the growth of unhealthy bacteria.
Antibiotics kill the good and bad bacteria in our gut. Sometimes we need to take antibiotics to kill a dangerous bacterial infection, but sometimes they are unnecessary. Try to take antibiotics only when you need them.
Many large-scale farming operations treat animals such as cows, chickens and pigs to make them grow faster and prevent infections. Although sick animals are not supposed to make it into the food chain if they are being treated with antibiotics, it’s not a bad idea to avoid animal-based foods that have been given preventative or growth-promoting antibiotics.
Just as with the foods we should avoid, foods that help maintain a healthy balance of gut bacteria are foods we generally consider healthy. Some of these gut-friendly foods may come as a surprise.
Sometimes we fall into food ruts. Even if we’re generally eating well — but eating the same fruits and vegetables every week, our gut flora can lack diversity. Dysbiosis, inflammation, gout, colorectal cancer, insulin resistance and inflammatory bowel disease are linked to a lack of gut diversity.
If you tend to eat the same foods, try adding a new vegetable or fruit to your diet every week. For example, instead of broccoli, try cauliflower. Instead of using chicken in a dish, try substituting tofu or tempeh. If you always buy apples, buy a seasonal fruit instead.
Fermented foods contain bacteria and yeast which convert carbohydrates into acids or alcohols. These acids and alcohols are natural preservatives — and they promote the growth of beneficial bacteria. You’ll find a wide variety of fermented foods that will help boost your gut health, so if you don’t like one, try another.
Look for fermented foods that say they contain live cultures. Some contain a lot of sugar, salt and fat, so choose carefully. The best ones are kefir, tempeh, miso, kimchi, unsweetened yogurt, sauerkraut, some agedand cottage cheeses, pickles brined in salt (not vinegar)and unsweetened kombucha.
Remember, prebiotics are what our bacteria eat, so adding foods rich in prebiotics ensures they can survive and multiply. Foods rich in prebiotics include garlic, asparagus, spinach, Jerusalem artichokes, onions, green bananas, chicory root, raw dandelion greens, barley, apples, steel-cut oats, leeksand dark chocolate.
In addition to the foods and beverages we put into our bodies, certain lifestyle choices can negatively impact our gut microbiome. Research has found that cigarette smokers have a higher level of Bacteroidetes in their guts compared to nonsmokers. Bacteroidetes can become very harmful if they escape the intestines. Smoking also leads to a higher incidence of gastrointestinal conditions such as Crohn’s disease and ulcerative colitis.
A lack of physical activity can also negatively impact our gut health. Evidence has also determined that chronic stress and lack of sleep negatively alter our gut floraby increasing the numbers of harmful bacteria and decreasing the “good” bacteria.
As we noted above, we are only beginning to understand how our gut microbiome affects our mental and physical health. Exciting new research will likely find move evidence — and possibly better prevention and treatment for so many of the diseases that currently reduce our quality and length of life.