The myth: Drinking cider vinegar eases pain.

THE SCIENCE: Some “natural health” advocates contend that beta-carotene in apple cider vinegar destroys free radicals in the body that are involved in ravaging the immune system. But the amount of beta-carotene in apple cider vinegar is infinitesimal, and if that approach worked, anyone who ate carrots would be free of arthritis pain.

Others say joints become stiff when acid crystals harden in them and that the vinegar dissolves the crystals and flushes them from the body. Gout is the only form of arthritis that involves acid crystals (uric acid crystals, formed from an excess of uric acid in the body) – and cider vinegar certainly doesn’t relieve gout pain. Even if cider vinegar could break up acid crystals, “You can’t direct acid from your mouth to whatever part of the body you want,” explains Irwin Rosenberg, MD, a gastroenterologist and professor of nutrition at Tufts University in Boston.

THE BOTTOM LINE: Apple cider vinegar belongs in your kitchen, not your medicine chest.

The myth: Dairy products make arthritis worse.

THE SCIENCE: A number of years ago, Dr. Panush conducted a study in which he put people with RA on dairy-free diets or on placebo diets. The vast majority of those on the special diet fared no better than those on placebo regimens, according to the findings, published in 1983 in Arthritis & Rheumatism.

In fact, dairy foods appear to protect against gout. Researchers at New Zealand’s University of Auckland found that milk consumption led to a 10 percent decrease in serum urate concentrations, potentially reducing the risk for gout development, according to a study in the Annals of Rheumatic Diseases.

THE BOTTOM LINE: In a very few people, limiting dairy products may help ratchet down arthritis symptoms – but it could simply be because they have a degree of lactose intolerance. Dairy products are safe for most people with arthritis to enjoy.

The myth: Nightshade vegetables aggravate arthritis. 

THE SCIENCE: Tomatoes, potatoes, eggplants and peppers are among the many plants that fall in the nightshade category. All contain a chemical called solanine, which has been branded a culprit in arthritis pain, but no formal research has ever confirmed the claim.