A traditional Scandinavian beverage, fermented milk, can help reduce blood pressure in people with hypertension, a new study from Finland shows.

The drink has long been popular in Scandinavian countries, Dr. Riita Korpela of Valio Ltd. Research and Development in Helsinki, the study’s lead author, told Reuters Health in an E-mail interview. Valio makes a modern version, with juice added, and sells it in several European countries.

It is made by adding Lactobacillus to milk, which breaks down the milk protein casein into two types of protein fragments called tripeptides.

The tripeptides, isoleucine-proline-proline and valine-proline-proline, have been shown in animal studies to reduce blood pressure and also lower blood pressure in people with mild hypertension. According to Korpela and her colleagues, they work by blocking the blood-pressure-raising chemical angiotensin-converting enzyme (ACE), the same mechanism employed by ACE inhibitor drugs.

In the current study, the researchers randomized 94 people with hypertension who were not taking any medications to 150 mL of the fermented milk or a control drink twice daily for 10 weeks. Study participants underwent 24-hour blood pressure monitoring at the beginning of the study and at the end.

After 10 weeks, average systolic blood pressures - the top number in a blood pressure reading - were about four points lower in the group consuming the fermented milk, while diastolic pressure (the bottom number) was nearly two points lower.

Past researchers have estimated that a three-point reduction in systolic blood pressure reduces the risk of stroke by 10 percent to 13 percent, and the likelihood of heart attack by 7 percent, Korpela told Reuters Health.

“It is also important to notice, that this is a very natural way of treating enhanced blood pressure, without any adverse side effects,” the researcher added.

SOURCE: American Journal of Hypertension, December 2005.