Study Suggests Brown Adipose Tissue Involved in Increased Energy Expenditure after Capsinoids Ingestion

Capsinoids have been shown to increase energy expenditure, so the purpose of the research being announced has been to examine whether activation of brown adipose tissue has a role in this effect.

Jul 19 2010 --- Ajinomoto Co., Inc. and a group led by professor Masayuki Saito of Tenshi College in Sapporo, Japan have found that a single ingestion of capsinoids, a sweet chili pepper extract, appears to increase energy expenditure, especially in people with a high level of activity in brown adipose tissue. The research results were presented at the XI International Congress on Obesity 2010 (ICO 2010) on July 13 in Stockholm, Sweden.

The finding may have implications for controlling obesity, which is affected by the activation of brown adipose tissue according to recent studies.

Previous research with animals such as mice has shown that brown adipose tissue is involved in the regulation of energy expenditure and changes in body-fat levels. Brown adipose tissue in humans and several types of animals is mainly located around the neck and large blood vessels of the thorax. Fat is broken down in the mitochondria of brown adipose tissue cells to generate body heat. Although brown adipose tissue exists to some degree in human infants, the once-conventional view was that the tissue gradually deteriorates and is barely detectable in adults, with virtually no physiological role. In recent years, however, the group led by professor Saito has used PET imaging1 to confirm that brown adipose tissue is present in adults. Since the activation of brown adipose tissue is thought to have an effect on controlling obesity, the finding has attracted attention worldwide.

Capsinoids have been shown to increase energy expenditure, so the purpose of the research being announced has been to examine whether activation of brown adipose tissue has a role in this effect. The test measured energy expenditure in 18 men after a single 9 mg ingestion of capsinoids, or a single ingestion of a placebo, and the two results were compared. Based on PET imaging, the test subjects were divided into groups of 10 people with a high level of brown adipose tissue activity and 8 people with a low level of activity. Capsinoids’ effect on energy expenditure was then compared in the two groups.

Results showed that energy expenditure was greater after ingestion of capsinoids than a placebo among 18 people. In addition, the increase was greater in the 10-person group with a higher degree of brown adipose tissue activity. The suggestion is that the activation of brown adipose tissue is involved in the effect of increased energy expenditure after capsinoids are ingested.

Ajinomoto plans to continue its research to confirm the hypothesis that repeated ingestion of capsinoids may further activate brown adipose tissue.