Your immune system becomes activated when your body recognizes anything that is foreign—such as an invading microbe, plant pollen, or chemical. This often triggers a process called inflammation. Intermittent bouts of inflammation directed at truly threatening invaders protect your health.

However, sometimes inflammation persists, day in and day out, even when you are not threatened by a foreign invader. That's when inflammation can become your enemy. Many major diseases that plague us—including cancer, heart disease, diabetes and arthritis—have been linked to chronic inflammation.

One of the most powerful tools to combat inflammation comes not from the pharmacy, but from the grocery store. "Many experimental studies have shown that components of foods or beverages may have anti-inflammatory effects," says Dr. Frank Hu, professor of nutrition and epidemiology in the Department of Nutrition at the Harvard School of Public Health.

So, what can you do to incorporate more anti-inflammatory foods into your diet? Here are some tips:

• Eat plenty of fruits and vegetables: Fruits and vegetables are naturally anti-inflammatory and rich in antioxidants, which can help reduce inflammation and improve overall health.

• Choose healthy fats: Omega-3 fatty acids, found in fatty fish, nuts, and seeds, are anti-inflammatory and can help reduce the risk of heart disease.

• Avoid processed foods: Processed foods are often high in sugar, salt, and unhealthy fats, which can contribute to inflammation. Choose whole, unprocessed foods instead.

 A healthy diet is beneficial not only for reducing the risk of chronic diseases, but also for improving mood and overall quality of life.