Many of these supplements can put patients at risk during surgery and they should stop taking them at least two weeks before their procedure, Dr. Bahman Guyuron and colleagues at Case Western Reserve University advised.
The investigators examined the medication lists of 200 patients scheduled for cosmetic facial plastic surgery -- such as a facelift or nose job -- and found that 49 percent of the patients were taking at least one type of supplement.
Overall, the patients were taking 53 different types of supplements. The average number of supplements was nearly three per patient, but one patient was taking 28 different supplements, according to the study in the July issue of the journal Plastic and Reconstructive Surgery.
Older patients and women were most likely to be taking supplements, according to a journal news release.
One-quarter of the patients were taking vitamin and mineral supplements only, most commonly multivitamins, vitamin D, calcium and vitamin B. Twenty-two percent were taking animal- and plant-based supplements -- most often fish oil -- in addition to vitamins and minerals. Just 2.5 percent of patients were taking animal- and plant-based supplements only.
Thirty-five patients were taking supplements linked with an increased risk of bleeding, such as bilberry, bromelain, fish oil, flaxseed oil, garlic, methylsulfonylmethane (MSM), selenium and vitamin E.
In addition to the supplements linked to bleeding risk, other popular supplements with potential harmful effects include echinacea, ephedra (ma huang), ginkgo, ginseng, kava, St. John's wort, valerian, feverfew and ginger.
The patients in the study were told to stop taking supplements two to three weeks before surgery.
"These high-risk supplements . . . are quite commonly used and the surgeon must elicit a complete history in order to avoid the known adverse consequences of supplement use on surgical outcome," the researchers wrote.