Harvard gut doctor avoids these 4 foods that cause inflammation—and what she eats instead

Inflammation is an essential process that increases blood flow to an infected area of the body, and carries in immune system cells to heal it.

But it can be uncomfortable, and chronic inflammation can damage healthy cells while creating a series of unpleasant symptoms such as joint stiffness, muscle pain and digestive issues.

As a gastroenterologist and associate professor of medicine at Harvard Medical school, I'm often asked how to fight inflammation. This is tricky, because it can be caused by many uncontrollable factors like autoimmune diseases or exposure to toxins.

But over the last few years, we've learned that foods have a large impact on inflammation. Some foods decrease healthy, anti-inflammatory bacteria in the gut, while others produce compounds that decrease inflammation and improve healing.

Here are four foods I try to avoid that cause inflammation:

Research shows that fatty meats like beef, pork and lamb are associated with low-grade inflammation.

Animal fats and saturated fats can alter your gut bacteria by increasing lipopolysaccharides, which can trigger inflammation. They can also cause changes that decrease short-chain fatty acids, which are anti-inflammatory and important to colon health.

What to eat instead:

• White meats from chicken and turkey are low in saturated fat.
• Fish are low in saturated fat and high in omega-3 fatty acids and other compounds that produce the substances that reduce inflammation.

These foods go through processes like extrusion or molding and tend to contain many additives or substances extracted from foods. Think: a hot dog instead of lean pork.

Their high amounts of saturated fat, salt and added sugar are associated with inflammation. They often lack the antioxidant properties of the whole foods they replace.

For example, white bread is missing the antioxidants of the wheat grain that make whole-grain breads anti-inflammatory.

What to eat instead:

• Fresh fruits and vegetables are rich in compounds called polyphenols that inhibit inflammation.
• Whole-grain foods contain antioxidants of the wheat bran and germ, and can be anti-inflammatory.

Soda and sugary drinks are associated with diabetes, obesity and cardiovascular disease — all of which can cause chronic inflammation. So I always recommend limiting intake.

What to drink instead:

• Oolong, black and green tea contain large amounts of polyphenols that inhibit inflammation.
• Coffee has been shown to decrease inflammation in some studies.

These oils can be found in processed foods (like large-brand cookies) and are sometimes used in cooking.

They contain high levels of saturated fats, which can decrease gut diversity and free fatty acids, potentially resulting in increased inflammation.

What to eat instead:

• Extra virgin olive oil is low in saturated fat, and contains polyphenols and other antioxidant, anti-inflammatory substances.
• Flaxseed oil is low in saturated fat and rich in anti-inflammatory omega-3 fatty acids.

Dr. Jacqueline Wolf, MD, is an associate professor of medicine at Harvard Medical School and a gastroenterologist at Beth Israel Deaconess Medical Center in Boston. She is the author of "A Woman's Guide to a Healthy Stomach: Taking Control of Your Digestive Health" and co-founder of Foodicine Health, a food education non-profit.

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