Dutch and US researchers have concluded that a low dose of the hormone melatonin may help lower blood pressure. In a small study of 16 middle-aged men with untreated hypertension, the researchers administered 2.5 mg of melatonin 1 hour before bed each night for 3 weeks. Also, the patients took a placebo for 3 weeks.
The findings indicated that participants who received nightly melatonin supplements lowered their nighttime systolic blood pressure by ~6 mm Hg on average and their diastolic reading by ~4 mm Hg. No change was seen from taking 1 dose of melatonin, the researchers noted in Hypertension (February 2004).
One study linked multiple pregnancies to an increased risk of developing atrial fibrillation later in life, and another investigated the association between premature delivery and cardiovascular disease.
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