Hair Growth Basics
Hair grows in three phases: growth (anagen), regression (catagen), and rest (telogen)[1].
{?|on average, hair grows about 1 cm (half an inch) per month - this rate is determined by genetics and cannot be significantly increased by products}
{?|hair length is limited by how long each follicle stays in the growth phase - this is genetic, which is why some people can grow longer hair than others}
Washing Frequency Myths
Myth: Washing hair daily damages it or makes it oilier
Reality: No scientific evidence shows that washing frequency affects sebum production. Oil production is controlled by hormones and genetics, not washing habits.
Reality: No scientific evidence shows that washing frequency affects sebum production. Oil production is controlled by hormones and genetics, not washing habits.
Myth: "Training" your hair to produce less oil works
Reality: The sebaceous glands that produce oil are not influenced by how often you wash. They respond to hormones, not external stimulation.
Reality: The sebaceous glands that produce oil are not influenced by how often you wash. They respond to hormones, not external stimulation.
Treatments That Work
Minoxidil is the most well-studied over-the-counter treatment for hair loss[2].
Supplements and Myths
Myth: Biotin supplements help everyone grow thicker hair
Reality: Biotin only helps those with an actual biotin deficiency, which is rare[3].
Reality: Biotin only helps those with an actual biotin deficiency, which is rare[3].
Myth: Cutting hair makes it grow faster or thicker
Reality: Hair growth happens at the follicle under the skin. Cutting the ends has no effect on growth rate or thickness.
Reality: Hair growth happens at the follicle under the skin. Cutting the ends has no effect on growth rate or thickness.
Myth: Brushing 100 strokes per day makes hair healthier
Reality: Excessive brushing can actually damage hair by causing breakage and split ends. Gentle detangling as needed is sufficient.
Reality: Excessive brushing can actually damage hair by causing breakage and split ends. Gentle detangling as needed is sufficient.
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References
- Lin X, Zhu L, He J (2022). Morphogenesis, Growth Cycle and Molecular Regulation of Hair Follicles. Frontiers in Cell and Developmental Biology. [DOI]
- Suchonwanit P, Thammarucha S, Leerunyakul K (2019). Minoxidil and its use in hair disorders: a review. Drug Design, Development and Therapy. [DOI]
- Patel DP, Swink SM, Castelo-Soccio L (2017). A Review of the Use of Biotin for Hair Loss. Skin Appendage Disorders. [DOI]