A new federal report reveals that Americans spend about $30 billion a year on complementary health approaches, from ginkgo biloba to yoga.

Complementary medical approaches are alternative types of healing outside the realm of Western medicine, and they’re fairly popular in the U.S. An estimated 60 million Americans spend money on them each year, and 4.1 million children have used some type of complementary medicine, the report reveals. In all, the out-of-pocket costs for these types of therapies total $30.2 billion.

The study doesn’t break down what types of complementary health approaches are the most popular, but people reported using acupuncture, Ayurveda, homeopathy, naturopathy, chelation therapy, natural product supplements, special diets, massage, mind-body therapies, hypnosis, energy healing and more.

Families with incomes under $25,000 spent an average of $435 each year on complementary health, and families with incomes of $100,000 or more spent about $590. Complementary medicine still makes up only a small portion of U.S. health care spending—around 1%—but the study authors note that the out-of-pocket costs to Americans are substantial.

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