What research suggests: "We're beginning to realize that fish oils are quite powerful," Lee pointed out. Fish oils are one of the many things that can help with high triglycerides and elevated lipid and cholesterol levels. Additional research is starting to look at the supplement's effect on asthma, ADHD, depression, atherosclerosis, and age-related macular degeneration.
Bottom line: There's a growing body of evidence suggesting that fish oils have positive effects on cardiovascular risk factors, but we still don't have data that it will affect cardiovascular mortality, said the NCCAM survey researchers. As Lee puts it, fish oils are inexpensive compared with other supplements, and they may be very effective for a broad range of conditions associated with inflammation.
What it is: Glucosamine is a compound that's found naturally in healthy cartilage, a connective tissue that covers the joints. But the supplement is derived from the shells of shrimp, crab, and other types of shellfish.
What it's supposed to do: It's been recommended for the treatment of osteoarthritis (OA), and in people at high risk for OA, or those who have already had a joint injury, it might be suggested to help prevent arthritis. Glucosamine might help build or rebuild damaged cartilage in people with OA.
What research suggests: The most convincing studies for glucosamine have examined its effectiveness in mild to moderate knee osteoarthritis, said Dr. Adam Rindfleisch, an assistant professor at the University of Wisconsin Family and Integrative Medicine Clinic in Madison. But he explained that there has been a lot of debate about how the studies have been carried out. The majority of them have used glucosamine hydrochloride, but some scientists suspect that glucosamine sulfate might be the form with the more powerful effect.
"My socks aren't knocked off by the most recent research, and it's not cheap to take," cautioned Rindfleisch.
Bottom line: Although some people might get some mild nausea as a side effect of glucosamine, Rindfleisch says he recommends the supplement (along with chondroitin) because he has seen it make a marked difference in some people with osteoarthritis.
"Give it a shot for at least six weeks or up to six months, and if you're not seeing a difference, then lay off," he advised. The typical daily dose is 1,500 milligrams of glucosamine, taken in divided doses of 500 milligrams three times a day.
What it is: Echinacea, also known as purple coneflower, is a member of the daisy family. People who have allergies to other daisy family members, including ragweed, marigolds, daisies, and chysanthemums, could also be sensitive to it.
What it's supposed to do: Echinacea is believed to help boost the immune system to fight off infection, most typically the common cold and other upper respiratory infections. It's been studied for its role in helping to shorten the duration and severity of a cold and for preventing it in the first place.
What research suggests: Even in the best data, echinacea never appeared to be a home run, noted Dr. Brent Bauer, director of the complementary and integrative medicine program at the Mayo Clinic in Rochester, Minn. "The overall enthusiasm for the herb has been appropriately dampened because we haven't seen many good studies coming up positive," he added.