You may have heard that your gut is your second brain. The saying gives a sense of how vital your digestive system is to the rest of your body.

But what does it mean? A network of hundreds of millions of nerve cells called neurons line the gut, or your gastrointestinal (GI) tract. The gut has the same kinds of neurons as the brain. And there’s also crosstalk between the gut and the brain.

The gut doesn’t just control things like our hunger and digestion. It’s a huge part of our immune system. It even contributes to mental well-being, says Wu Tsai Neurosciences Institute at Stanford University.  GI issues are also often linked to neurological health problems such as Parkinson’s. And 60 percent of people with generalized anxiety also have irritable bowel syndrome.

How your gut is working has a big impact on your daily life. And millions of Americans have at least one digestive problem. So how can you keep your gut healthy?

Immune Health and What You Eat

If you want to boost your immunity, look to the gut, says UCLA Health.  That’s because 70 percent of the immune system is found in the gut.

Immune cells in the gut interact with all kinds of bacteria and fungi that live there. What you eat and how you take care of your body change the mix. Those gut bugs are healthiest and support strong immunity when you eat plant foods that are high in fiber.

A diet high in animal proteins, sugar, processed foods and saturated fat creates gut bacteria that cause inflammation and life-long health problems.

A fiber-rich diet, on the other hand, lowers the inflammation response. Think fiber-filled plant foods like apples, broccoli, yams and zucchini.

Having extra weight also alters immune function. Fat tissues send out hormones and chemicals that fire up inflammation.

There are ways to help your gut help you. The main drivers of gut health change are shifts in stomach acid, gut immunity and the mix of bacteria in your digestive system. When gut health is good, you’re less likely to have harmful inflammation and breaks in immunity, says Johns Hopkins Medicine. 

To improve your gut health through diet, try to:

• Pump up the plants. Aim for five to seven servings of fruits and vegetables a day.
• Eat good fats. They support immune function. Use olive oil to cook and add avocado slices to your salads.
• Eat wild-caught fish; it’s healthier than farmed varieties.
• Have protein at each meal, instead of only at dinner. Spread it out. The immune system runs better on more regular servings of protein. Your protein can come from animal products. But don’t forget that plant sources like beans and lentils can be healthier choices.
• Add spices and herbs to your foods. They add flavor and also support gut-bug diversity.
• Try fermented and pickled foods, like kefir, kimchi and sauerkraut.

More Ways to Boost Your Gut Health

Taking care of yourself will help your immune system take care of you, says the Centers for Disease Control and Prevention. Since everything in your body ties together, what you eat is important, but it’s just one part of gut health.

There are other important ways  to keep your gut, and the rest of you, healthier:

• Get more sleep.
• Get more exercise.
• Get a handle on your stress.
• Get help for anxiety and depression.

Making some changes to your life can charge up your immune system for overall better mental and physical health.

Sources: If you want to boost immunity, look to the gut,  UCLA Health, 2021; Your gut - the second brain?  Wu Tsai Neurosciences Institute at Stanford University, 2023; Your Digestive System: 5 Ways to Support Gut Health,  Johns Hopkins Medicine; Six Tips to Enhance Immunity,  Centers for Disease Control and Prevention, 2023