Healthy Gut, Healthy Body

Have you thanked your microbiome lately?

If you just said, “My what?” you’re not alone. “Microbiome” is the name for the diverse population of microorganisms that live in your body, including viruses, bacteria and fungi. We’re talking trillions of microbes, happily residing in your gut, on your skin and just about every other part of you.

“Wait,” you’re probably thinking. “Viruses, bacteria and fungi? Aren’t those bad for my health?” Yes and no. Your body shares a symbiotic relationship with your microbiome (also known as your “microbiota”). Some microbes do make us ill, but many others play a significant role in keeping us well. In fact, the microbiome is so important to human health that many experts now think of it as an essential organ.

Most of your microbiome lives in your large intestine. Gut science is a relatively new field, but researchers are teasing out connections between our intestinal microbes and different systems in our bodies. Here’s what the research says:

• Digestion: Gut bacteria have several jobs, including breaking down dietary fibre and sugar, producing vitamin K and some B vitamins, and helping to protect your intestinal lining.
• Immune system: The gut microbiome may play a role in controlling the immune system. In the future, it may even be possible to use gut bacteria to “activate” an immune response to fight disease.
• Brain: Gut bacteria produce neurochemicals that influence your mood – including serotonin and dopamine – as well as chemicals that affect memory and learning.
• Heart: There may be a connection between the microbiome and our heart health. It sounds like science fiction, but someday, it may be possible to reduce the risk of cardiovascular disease by tweaking the health of our gut bacteria.
• Weight: Gut bacteria may have a role in regulating weight gain. If it’s true that our microbes have a say in how much energy and nutrition we extract from the food we eat, that means we could one day have weight-loss plans customized for our microbiomes.

Eating for a healthy microbiome

It’s too early to say what makes an ideal microbiome – and it’s very likely that this will vary from person to person – but the experts have a few tips we can follow:

• Aim for diversity: Eat a wide range of healthy foods, with an emphasis on plants – legumes, fruit, vegetables, beans and other fibre-rich choices. (For inspiration, check out the recently revamped Canada’s Food Guide to Health Eating.)
• Try fermented foods: If you’ve never eaten sauerkraut, kefir, yogurt, kimchi, kombucha or tempeh, give them a try. These foods are not only rich in health-boosting probiotics (live microorganisms), but they’re delicious, and it’s fun to learn new recipes.
• Prioritize prebiotics: Prebiotics are foods that promote the growth of probiotics. To get more prebiotics in your diet, eat asparagus, garlic, leeks, bananas, onions, tomatoes, Jerusalem artichokes, whole grains and chicory root.
• Limit packaged and processed foods: Convenience foods tend to contain a lot of additives and preservatives. These chemicals may interfere with healthy gut bacteria.
• Avoid artificial sweeteners: In a study published in 2018, aspartame and other artificial sweeteners were found to be toxic to digestive gut microbes.
• Don’t misuse antibiotics: Suffering from a cold or the flu? Antibiotics won’t help you recover any faster, yet many Canadians insist that their doctors prescribe them. Not only is this contributing to antibiotic resistance, but these drugs are harmful to your gut bacteria.
• Quit smoking: Cigarettes have been shown to boost bad bacteria and decrease good bacteria.

In addition to improving your diet, strive to get adequate sleep, exercise regularly and minimize stress – all of which can have a beneficial effect on your all-important microbiome.

Additional resources

Prebiotics and Probiotics (Dietitians of Canada)