A study published in the journal Antioxidants suggests that luteolin, an antioxidant found in vegetables like broccoli and celery, may help slow the progression of gray hair.
Experiments to test the effects of luteolin, both topically and orally, were conducted by researchers at Nagoya University in Japan. The scientists used mice that had been genetically modified to mimic the human condition of premature graying. Middle-aged humans experience a decline in pigment cells, or melanocytes, within their hair follicles. These pigment-producing cells are responsible for the range of natural hair colors, from blonde to black. As we get older, the amount of melanin produced by melanocytes drops steadily, and some people experience a more rapid loss of it. Eventually, the hair emerges from the follicle without pigment, either gray (if some pigment remains) or white (if no pigment remains), since the cortex, the main part of the hair, is pigmented only when melanocytes are miraculously still producing (some of) the amount of melanin that it’s supposed to produce.
For 16 weeks, the researchers gave luteolin to the mice either as a supplement or as a topically applied medicine. All the mice began the study with about 20% of their fur gray. By the end of the study, though, the mice that had been given luteolin had almost no increase in the amount of gray fur they showed, while the untreated mice had fur that was gray 60% to 80% grey.
The study noted that these results suggest that both external and internal treatments with luteolin can potentially suppress hair graying through similar mechanisms. They also noted that external application of luteolin proved to be more effective than oral treatment. The researchers found that the oddball mice, which had been treated with luteolin, maintained levels of endothelin. Typically, this peptide’s levels decrease when hair turns gray, but it’s also necessary for hair pigment production. On top of that, the researchers observed that luteolin’s antioxidant properties might be preventing the natural aging of the cells that produce pigment for hair.
Potential Implications for Humans
The study’s lead researcher, Professor Masashi Kato, stated, “Although we cannot say for certain that it will have the same effect on human gray hair, a balanced diet that includes luteolin-rich foods may help suppress the progression of gray hair.” He went on to suggest that the basic biological mechanisms might be quite similar between humans and the animals used in the research.
Earlier studies have associated the lack of nutrients with early graying, though the association is dubious at best. Nutrients that are essential for melanin production are undoubtedly linked to the health of the hair. Their absence—due to a deficiency in the diet, for instance—could lead to a disruption in the normal functioning of hair follicles and potentially to graying. But many factors influence natural graying, including genetics, age, medical conditions, and other aspects of one’s lifestyle, like stress, smoking, and pollution. Nutritional deficiencies may speed up the process in some people but are hardly ever the sole reason for going gray.
Kato and his team are hopeful that further investiation into human hair may soon shed light on the development of treatments to prevent or slow the onset of gray hair. For now, they say, the best thing people can do is maintain a balanced diet rich in the kinds of nutrients that are vital for hair health—luteolin among them.
