Bad Effects of Maca

The maca is a vegetable that looks like a radish. In Peru, the natives have used maca to increase energy and endurance and to promote sexual virility. Although maca was traditionally used in vegetable form, you can find dried maca supplements in many drugstores in both pills and extract form. According to Drugs.com, lab studies have shown maca's toxicity to be very low, with few adverse reactions and side effects. You should still speak with your doctor before taking this or any other supplement, especially since there has been very little research into maca's interactions with other drugs.

Breast Tenderness

According to Beth M. Ley, author of "Maca: Adaptogen and Hormonal Regulator," women who take high doses of maca supplements may experience a slight tenderness in the breast area. This is a result of maca's effects on hormone levels and should be considered a signal to take a lower dosage of maca.

Insomnia

Dr. Ray Sahelian states that those taking high doses of maca may experience insomnia, especially if the supplement is taken shortly before bed. Maca has a variety of components such as glucosinolates, macamides, uridine, malic acid and sterols. According to Dr. Sahelian, the majority of these components can interact negatively with your central nervous system, although the exact reason for the effects needs further research to be understood completely.

Goiter

Drugs.com recommends that those who have any type of thyroid condition should avoid taking maca in any form. If the glucosinolates found in maca are used in conjunction with a diet that does not contain enough iodine, goiter can occur. According to Cornell University in New York, glucosinolates are included in organic compounds that have been found to show antithyroid activity. Radishes, watercress and horseradish are some of the other plants that are commonly known to contain glucosinolates. Along with maca, these plants are used frequently to create a bitter, hot or spicy taste to many foods and condiments.