When Medical Reversals Happen

A medical reversal is when new research leads to a complete change in a medical practice or treatment that was previously widespread — often the result of new, better-designed studies contradicting current practice.

Examples:

• Hormone replacement therapy (HRT): for years recommended to postmenopausal women to counteract aging and help prevent heart disease; stopped when considered too risky due to association with increased cancer, stroke, and blood clot risk; more recent research has shown complex risks and benefits, and it is again being recommended to some women, though still considered inappropriate for chronic disease prevention in postmenopausal women generally.
• Knee surgery: arthroscopic surgery for meniscal tears in patients over 45 with osteoarthritis was common prior to studies showing these patients do better with non-surgical management including physical therapy.
• MRI testing for back pain: once routinely done for low back pain, until research found that a large sample of people with no back pain complaints also had herniated discs — now conservative management, including physical therapy, is almost always prescribed first.
• Vitamin D screening (a recent reversal): new Endocrine Society guidelines (June 3, 2024) advise against routine vitamin D testing in healthy people, recommending 600 IU daily for most adults 19–70 (increasing to 800 IU for those over 70) from dietary and supplemental sources combined — aligning with National Academy of Medicine recommendations. These guidelines, the result of a comprehensive systematic review, have already sparked significant controversy.

Joanne's Thoughts. It's reassuring that medical researchers continue to re-evaluate established practices, even if this sometimes results in a "flip flop" that can temporarily undermine confidence in the medical system — in most cases the new recommendation simply reflects the scientific process working as intended, which is a good thing. Read the latest medical news with a critical eye and an open mind, expecting practice to continue evolving as we learn. One area with no reversals: the growing body of research on the importance of exercise to many aspects of health and well-being — that evidence base just continues to grow.

References

1. Manson JE, et al. The Women's Health Initiative Randomized Trials and Clinical Practice: A Review. JAMA 2024 May;331(20):1748-1760.
2. Kirkley A, et al. A Randomized Trial of Arthroscopic Surgery for Osteoarthritis of the Knee. New England Journal of Medicine 2008;359:1097-1107.
3. Moseley JB, O'Malley K, Petersen NJ, et al. A Controlled Trial of Arthroscopic Surgery for Osteoarthritis of the Knee. New England Journal of Medicine 2002;347:81-88.
4. Koes BW, et al. Diagnosis and Treatment of Low Back Pain. British Medical Journal 2006 June;332(7555):1430-1434.
5. Demay MB, et al. Vitamin D for the Prevention of Disease: An Endocrine Society Clinical Practice Guideline. Journal of Clinical Endocrinology and Metabolism 2024 Jul 12;109(8):1907-1947.
6. Medscape: "D-Day: Vitamin D Disease Prevention Guideline 2024."