Fish oil is the most common natural product taken by children and adults. Some studies show it has anti-inflammatory effects.
Probiotic use was four times as high in 2012 as it was in 2002, according to the NIH. Probiotics found in yogurt are "good" bacteria that can prevent stomach problems, according to some studies.
Prebiotics, the nondigestible carbs that the probiotics eat, help promote their growth. They can be found in bananas, onions, garlic and honey and can improve stomach health.
Some adults and children take melatonin, a hormone that scientists think may help regulate sleep cycles. Studies show it can help people who have trouble sleeping.
The number of adults practicing yoga more than doubled since 2002, according to a new study. More than 21 million adults and 1.7 million children practice yoga.
Some 10.9% of adults practice deep breathing to relieve stress and anxiety. They also practice breathing as a part of meditation exercises.
Nearly 20 million adults and 1.9 million children go to a chiropractor for pain. Chiropractors can help with back issues and neck pain.
Fewer American adults took the herb echinacea than they did in the past. It has been thought to reduce cold symptoms, but studies show conflicting results after its use.