Melatonin supplements may effect blood pressure

Before Taking Melatonin Supplements, Talk With Your Doctor if you have High Blood Pressure

At night, when your body is at rest, blood pressure drops as your body’s natural production of the hormone melatonin rises. And according to Italian researchers, these two functions are interrelated.

The Italian team recruited 18 women; half were healthy and half were taking medications to control high blood pressure. Subjects were randomly chosen to receive a melatonin supplement or a placebo for three weeks. After this first phase, the melatonin group crossed over to placebo and the placebo group crossed over to melatonin for another three weeks.

Researchers found that nighttime blood pressure decreased with melatonin use, while the day-night blood pressure ratio increased. Studies have shown that a low day-night blood pressure ratio may be associated with elevated heart disease risk.

If you have high blood pressure, there are a few points you should discuss with your doctor before trying melatonin supplements.

In previous e-Alerts, HSI Panelist Allan Spreen, M.D., has explained how useful melatonin supplements can be in relieving jet lag. But other than occasional use for travelers, Dr. Spreen does not recommend melatonin for anyone under the age of 40.

Dr. Spreen: “As we age, melatonin production decreases, so I’m not as nervous for someone over age 40 using it as a ‘youth’-type agent, and I think there’s something to it. The substance is well researched to be both an antioxidant, and a nutrient of considerable worth in other areas. The cautious types talk about 1.5 mg at bedtime (never anytime but bedtime), for ages 40 to 50, then 3 milligrams for people over age 50. I subscribe to that. Those who take lots more I think are swimming in uncharted waters – nobody has any real data that it’s bad (nor that it’s not).”

If you’re wary of melatonin supplements, you can try increasing your intake of melatonin-rich foods, which include bananas, cherries, ginger, tomatoes, corn, cucumber, beets and rice. And always turn off the lights while you sleep. Sleeping with the lights on may inhibit your body’s natural production of melatonin.

Sources:
“Sleep Hormone May Protect Heart” Reuters Health, 1/31/06, reutershealth.com