Science Daily takes a look at propolis, the sticky putty-like stuff honeybees use to seal up their hives. There are all kinds of health claims made about it, but one study shows that it can boost hair growth:
People from ancient times had noticed propolis’ special properties and used it to treat tumors, inflammation and wounds. More recently, research has shown that the substance promotes the growth of certain cells involved in hair growth though no one had yet tested whether that in turn would result in new locks.
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When [Ken Kobayashi and his team] tested propolis on mice that had been shaved or waxed, the mice that received the treatment regrew their fur faster than those that didn’t. The scientists also noticed that after the topical application, the number of special cells involved in the process of growing hair increased.