Probiotics: Healthy bacteria for your gut

Your gut is home to 100 trillion microorganisms or microbes. These gut bacteria – some good, some bad – play a vital role in your health.

“Your intestines hold about 10 pounds of microorganisms. And each person has a unique blend that starts forming at birth,” says Erma Levy, a research dietitian in Behavioral Science at MD Anderson. As you grow, where you live and what you eat affect this blend of good and bad bacteria. These gut bacteria – some good, some bad – play a vital role in your health.

Probiotics are the good bacteria. And they may help lower your risk for several cancers. “Probiotics help your immune system function at its best so it can detect and kill cells that can become cancer,” Levy says.

Much of the probiotics research focuses on colon cancer, because most microorganisms live in your intestinal tract, she says. “And while more research is needed, several studies show that people with colon cancer have an unhealthy population of gut bacteria before the cancer develops.”

So how do you keep your gut bacteria healthy? 

Feed it a balanced diet.

Your diet sustains your gut bacteria. “We’re their host. We provide an environment and food. And they help us digest food and convert essential vitamins and nutrients into an absorbable form,” Levy says.

So treat your gut like a garden, not a gutter, she says. “You seed your garden with probiotics and fermented foods and feed it with prebiotic or fiber-rich foods.”

Add good bacteria with probiotic foods

Probiotic foods contain live bacteria, which may help restore balance and offer protection from harmful bacteria. Eating them is one way to reseed your gut with good bacteria, Maxson says.

Plus, early research shows that the anti-inflammatory effects of probiotics could inhibit the growth of breast cancer cells.

Probiotic foods include:

• Low-fat, plain organic yogurt with live or active cultures
• Kefir (a yogurt-like drink)
• Kombucha tea
• Fermented vegetables like sauerkraut and kimchi
• Fermented soybeans (miso)

To get the most health perks, eat at least one small serving of probiotic foods each day. If you’re considering a supplement, speak with your doctor.

Support your gut health with prebiotic foods

Prebiotic foods feed the bacteria in your gut so they can grow and repopulate. Most are fiber-rich plant foods.

Prebiotic foods include:

• Whole grains
• Fruits and vegetables, specifically bananas, asparagus and onions
• Oatmeal
• Soy beans
• Garlic

Try to fill at least two-thirds of your plate with plant foods. A well-balanced diet that is high in prebiotic foods can have significant health benefits and help keep your gastrointestinal system healthy.

Limit processed foods 

Processed foods are often low in nutrients and high in added sugar and salt. Processed foods include fast food and packaged foods. Eating too many of these can wreak havoc on your gut bacteria.

“People who eat a diet high in processed foods and low in fruits and vegetables have a lower diversity of microorganisms,” Levy says.

Most scientific studies indicate that both the diversity and the composition or balance of gut bacteria are important. Gut bacteria also appear to play a role in weight gain and obesity.

“Studies show that people who are leaner tend to have a greater variety of microorganisms,” Levy says. And being overweight or obese raises your risk for many types of cancer. This includes colon, postmenopausal breast and endometrial cancers.

The research is too new to know which gut bacteria makeup is ideal to maintain a healthy weight and reduce disease risk. “But it’s clear that variety and balance are important,” Maxson says.

It’s never too late to change your diet

When you change your diet, a significant change in your microorganism population takes place within a couple of weeks.

“We’re just learning the benefits of a healthy population of gut bacteria,” says Levy. In addition to optimal immune function and lower cancer risks, studies show a healthy mix can affect your mood. Studies indicate that our gut bacteria and brain communicate with each other. Changes in gut bacteria have some influence on behavior, anxiety and depression.

So, for your health’s sake, take care of your gut. 

Request an appointment at MD Anderson's Lyda Hill Cancer Prevention Center online or call 877-632-6789.