The following health newsletters are considered the top five by experts in the field. They are listed in the December issue of CHANGING TIMES magazine. All are published monthly and prices listed are for a year's subscription. You can get a free copy by sending a self-addressed, stamped envelope to the address given.

- "Consumer Reports Health Letter," (Box TTB, 256 Washington St., Mount Vernon, NY 10553, $24). Tough-minded and practical, it blends consumer advocacy with authoritative research, CHANGING TIMES says. Topics range from calcium supplements and bad breath to whether you get more for your money buying drugs mail-order or retail.- "Harvard Health Letter" (164 Longwood Ave., Boston, MA, 02115, $24). Condenses current medical information primarily about diseases and their treatments. Recent topics: treatment of lower back pain, including chiropractic, and a series on heart failure.

- "Mayo Clinic Health Letter" (200 First St., S.W., Rochester, MN 55905, $24). This is aimed at the over-60 crowd with easy-to-read graphics and an encyclopedic, but understandable, approach. Looks at diseases and disorders from diagnosis to treatment, mostly from a doctor's point of view. Recent issues cover coronary bypass surgery and carpal tunnel syndrome.

- "Public Citizen Health Research Group Health Letter" (Public Citizen Health Research Group, 2000 P St., N.W., Dept. CT, Washington, DC 20036, $18). Keeps readers informed on slipups at the Food and Drug Administration, drugs to avoid, and federal legislation worth watching.

- "University of California, Berkeley, Wellness Letter" (48 Shattuck Square, Suite 43-C, Berkeley, CA 94704, $20). This is written by science writers in New York City and reviewed by Berkeley faculty. Mostly concerns preventive health issues such as whether to eat sushi or bleach your teeth and how to prevent Lyme disease or sports injuries.