Nightshades

Nightshades are a plant family that includes tomatoes, potatoes, eggplant, hot peppers, and sweet bell peppers. Spices and condiments derived from these foods, including cayenne, paprika, and Tabasco sauce, also fall into the nightshade family. Nightshades can aggravate joint inflammation, so many health professionals tell patients with all types of arthritis to steer clear of these foods, although it seems that only certain people are sensitive. Nightshades contain a toxic alkaloid called solanine, which is normally destroyed in the intestines. Solanine irritates the gastrointestinal tract and can also cause diarrhea, headache, and vomiting.

What you can do: Avoid green tomatoes, green potatoes, and sprouted potatoes, which contain higher levels of toxic alkaloids. Cooking nightshades reduces their alkaloid content by 40 to 50 percent, but if you're sensitive, you might try eliminating them from your diet temporarily. Experts are split on the amount of time it takes to see true results; some say two to three weeks is a good trial; others recommend a minimum of six weeks.

If you're eliminating nightshades from your diet, it's the perfect time to ramp up your intake of foods that fight inflammation, particularly if you're prone to arthritis. Try these picks for super anti-inflammatory power: foods rich in omega-3 fatty acids, including flaxseed, walnuts, salmon, mackerel and sardines; pineapple; and onion, garlic, ginger, and turmeric.