Effect of topical application of raspberry ketone on dermal production of insulin-like growth factor-I in mice and on hair growth and skin elasticity in humans

In 2008, researchers found that raspberry ketone (RK) could potentially promote hair growth and improve skin elasticity. In mice, RK increased dermal insulin-like growth factor-I (IGF-I) and promoted hair regrowth. In human trials, 10 subjects with alopecia applied 0.01% RK to their scalp for 5 months, with 50% experiencing hair growth. Additionally, 5 female subjects experienced increased cheek skin elasticity after applying RK for 2 weeks. The study suggests RK's benefits may be due to its ability to enhance IGF-I production through sensory neuron activation. However, the small number of human participants indicates a need for further research with larger sample sizes.