article_snippet.sent: It usually takes more than two months for the hair follicles to begin to benefit from dietary changes and as hair only grows half an inch a month, it may take as long as six months before you begin to notice any changes,’ says Philip Kingsley.
article_snippet.sent: The caffeine in Alpecin caffeine liquid hair energiser (£7.49 for 200ml, from chemists) is said to stimulate weakened hair roots.
article_snippet.sent: Professor Andrew Messenger says that a study published last year shows caffeine can stimulate human hair growth in vitro, ie in a test tube.
article_snippet.sent: There have also been studies showing caffeine is absorbed quickly through hair follicles, suggesting caffeine could be active when used in a shampoo formulation.
highlights_snippet.sent: It takes more than two months for hair follicles to begin to benefit, Trichologist Philip Kingsley says .