Eating a combination of chili peppers and soybeans is likely to promote hair growth, according to a researcher at Kumamoto University.

Kenji Okajima, an assistant professor at the university's Graduate School of Medical and Pharmaceutical Sciences, found that a combination of capsaicin, the chemical that makes chili peppers spicy, and isoflavone, which is found in soy beans, helped restore head and eyebrow hair that had fallen out due to stress.

According to Okajima's research, capsaicin raises levels of calcitonin gene-related peptide, or CGRP, by stimulating the sensory nerves. CGRP in turn raises levels of an insulinlike growth factor, that is recognized as important for hair growth. Isoflavone promotes the production of CGRP.

In the study Okajima, who is a hematologist by trade, asked a man who was losing hair due to stress to take six milligrams of capsaicin--the amount found in about two grams of chili pepper--and 75 milligrams of isoflavone--the amount found in about 200 grams of bean curd--each day.

After about one month of the regime, the man's eyebrows and the hair on the top of his head started to grow back. Now, two months since he started taking capsaicin and isoflavone, his hair is said to be growing normally.