5 Worst Foods for Gut Health and the Microbiome
Your gut and the bacteria that live there are called the gut microbiome. It’s here that trillions of bacteria make their home and influence factors like nutrient absorption and even your immune system.
Factors like taking antibiotics and exercise can alter your gut microbiome in a negative way. However, what you eat matters too. In fact, diet has a major influence on the health of your microbiome. Certain types of foods are more likely to damage your gut microbiome and create havoc than others. Here are some of the worst foods for gut health.
Red meat contains a compound called carnitine. When you consume large amounts of carnitine-containing red meat, more bacteria that break down carnitine move in and their number increase. However, these bacteria produce another compound called trimethylamine N-oxide (TMAO) when they metabolize carnitine. Research suggests that TMAO causes plaque build-up inside arteries that carry blood to the heart. Your gut microbiome responds very quickly to dietary changes, in as little as a day or two. When you switch to eating more red meat, bacteria that produce artery-clogging TMAO become more abundant.
A glass of wine may have some health benefits due to the antioxidants it contains but don’t overdo it. Studies show that heavy alcohol use alters the gut microbiome in an unhealthy way. It’s not clear how much you have to drink to get this effect. However, one study found that drinking no more than one glass of red wine per day may increase the diversity of the gut microbiome. The type of alcohol may matter too. One study found that red wine boosted the number of healthy gut bacteria while gin increased the number of harmful bacteria. So, if you must drink alcohol, choose red wine and stick to one glass.
Some research also shows that using alcohol regularly, as little as one glass per day, may lead to small bowel bacterial overgrowth. This is where bacteria that are normally in the large intestinal tract move backward into the small intestines, creating problems with digestion and nutrient absorption.
Sugar is a source of empty calories and a contributor to weight gain and inflammation and insulin resistance. However, sugar may be harmful to gut health and the microbiome in a more direct way. A study in mice showed that sugar blocks proteins that support the growth of some healthy species of gut bacteria. So, eating a diet high in sugar could make it harder for the good bacteria to lay down roots and keep your gut healthy. So, cut sugar out of your diet.
Artificial sweeteners might sound like a healthier alternative to sugar if you like a little sweetener in your coffee or tea, but studies show artificial sweeteners may stymy the growth of healthy gut bacteria too. One study found that artificial sweeteners favor the growth of bacteria that extract more energy from food and contribute to weight gain. Other studies suggest that artificial sweeteners contribute to insulin resistance, a precursor to type 2 diabetes. So, don’t replace that sugar-sweetened soft drink with an artificially sweetened one and think you’re doing something good for your gut. The artificial sweeteners in these beverages may be just as bad.
Junk Food in General
As mentioned, a diet high in sugar contributes to insulin resistance and inflammation, and the release of inflammatory compounds may alter the composition of the gut microbiome in a negative way. However, junk food also contains unhealthy fats and are high in sodium. It’s not clear what impact each individual component has on the gut microbiome. However, studies show that eating a standard Western diet that includes lots of ultra-processed food is linked with unhealthy changes to the gut microbiome. Plus, when you eat ultra-processed junk food, it crowds foods that are good for your gut, like fiber-rich fruits and vegetables, out of your diet.
What Exactly does Microbiome Mean?
A community of microorganisms (such as bacteria, fungi, and viruses) that inhabit a particular environment and especially the collection of microorganisms living in or on the human body Your body is home to about 100 trillion bacteria and other microbes, collectively known as your microbiome.— merriam-webster
The Bottom Line
Now you know what not to eat to keep your gut microbiome healthy. What should you eat? Choose more fiber-rich foods, like fruits, vegetables, nuts, seeds, and whole grains. Also, enjoy probiotic-rich foods, like fresh sauerkraut and other fermented vegetables. Start your day with a container of yogurt with live cultures or enjoy probiotic-rich kombucha.
Eating a diversity of plant-based foods and fermented foods will help support the health of your gut microbiome!
PsychologyToday.com. “The Connection Between Sugar and Your Gut”
PBS.org. “Sugar Can Keep Good Microbes From Colonizing Your Gut”
ScientificAmerican.com. “Artificial Sweeteners May Change Our Gut Bacteria in Dangerous Ways”
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Alcohol. Volume 74, February 2019, Pages 105-111.
National Institutes of Health. “Gut microbes affect harmful compound in red meat”
J Transl Med. 2017; 15: 73.Published online 2017 Apr 8. doi: 10.1186/s12967-017-1175-y