The Truth About Hair Growth: Why Cutting Doesn't Speed It Up
For generations, many people have believed that regular haircuts make hair grow faster and thicker. This common beauty myth has been passed down through families and beauty salons, but what does science actually say about this widespread belief?
The Scientific Reality of Hair Growth
Desmond Tobin, professor of dermatological science at University College Dublin, provides a clear scientific perspective on this matter. "That's not true," he states definitively when asked about whether cutting hair makes it grow faster.
Hair grows from specialized structures called follicles, which are located 2-4mm beneath the scalp's surface. Inside these follicles, hair fibres form long before they become visible at the skin's surface. By the time hair emerges from the scalp and reaches the length we can cut, it has already become dead, hardened tissue.
"Cutting what's above the surface has no effect on what's happening in the follicle below," explains Professor Tobin. This fundamental biological fact means that trimming the ends of your hair cannot influence the growth process occurring deep within your scalp.
Understanding Hair Growth Cycles
Human hair grows at an average rate of approximately 1cm per month during its active growth phase, which typically lasts several years. After this period, the hair enters a resting phase before eventually being shed, and the entire cycle begins again with new growth.
This growth rate is primarily determined by genetic factors and cannot be accelerated through external interventions like cutting. The speed at which your hair grows is essentially programmed into your DNA, making it resistant to manipulation through simple trimming.
Why Hair Sometimes Appears to Grow Faster After Cutting
So where does this persistent myth originate? Professor Tobin offers an insightful analogy: "Think of trimming an unruly hedge. When you give it a good clip into shape, it can give the impression of being denser. You haven't changed what's happening in its deeper branches - you've just tightened up the overall appearance."
Hair behaves in a remarkably similar fashion. Individual hair strands naturally taper as they grow further from the scalp, so cutting them shorter makes them feel thicker and more substantial. Additionally, removing frayed, weathered ends through trimming can create the illusion of fuller, healthier-looking hair.
The Real Secret to Growing Longer Hair
If your goal is to achieve longer hair, Professor Tobin emphasizes that frequent trims should not be your primary focus. Instead, the key lies in minimizing damage to your hair.
"The advice would be to maintain the hair fibre in a virgin state with the least aggressive chemical or thermal exposure," he recommends. Heat styling tools and harsh chemical treatments can significantly damage the hair's outer shaft, making it brittle and prone to splitting.
When hair breaks faster than it grows, it creates the frustrating illusion that your hair isn't getting any longer, regardless of how frequently you trim it. By protecting your hair from damage and maintaining its health, you allow it to reach its maximum potential length.
Practical Hair Care Recommendations
To support healthy hair growth and appearance, consider these evidence-based approaches:
- Limit the use of heat styling tools like straighteners and curling irons
- Reduce exposure to harsh chemical treatments and dyes
- Use gentle hair care products appropriate for your hair type
- Maintain a balanced diet rich in hair-healthy nutrients
- Consider occasional trims to remove split ends and maintain hair health
While regular trimming won't make your hair grow faster, it can contribute to healthier-looking hair by removing damaged ends and preventing further splitting up the hair shaft.
