New Functional Claim for Maintaining Body Temperature Approved for NSK-SD® in Japan

The functional health claim “maintains peripheral body temperature” was approved for NSK-SD® in Japan on June 14, 2024. NSK-SD® is nattokinase derived from Bacillus subtilis natto and has been reported in clinical studies to maintain peripheral body temperature of hands and fingers by improving peripheral blood flow when outside temperatures or room temperatures are low, such as in cold weather or in air-conditioned rooms.

In a recent double-blind, placebo-controlled, crossover intervention study published on July 6, 2023, 9 male subjects were given a single dose of nattokinase or a placebo and then immersed their hands in a cold water bath for 1 minute. Skin temperature was then measured in intervals after immersion. The findings showed that the skin temperatures of the middle finger, palm, and back of the right hand recovered more quickly by nattokinase intake than by placebo intake (p < 0.05). It was also noted that nattokinase did not disturb the body’s normal circulatory response or sympathetic nervous system.

The results may especially pose benefit of nattokinase for individuals more sensitive to the cold, such as women and the elderly, through its potential to prevent excessive vasoconstriction.

Nattokinase has already been backed by numerous studies for its heart health benefits. These study results include the prevention and degradation of blood clots, reduction in high blood pressure, improvement of clumping platelets and red blood cells, improvement in blood flow, helping reduce inflammation, and more.

NSK-SD® also holds an approved functional health claim for improving hypertension. NSK-SD® has shown in multiple human studies to lower blood pressure in people with elevated blood pressure by improving peripheral blood flow.