Does Trimming Your Ends Make Hair Grow? Four Skin Myths
Many everyday beauty habits rest on ideas that biology does not support. We look at four common myths: what doesn't work, what does, and the mistake that turns a summer tan into dark spots over the years.
Trimming your ends doesn't make hair grow faster
Plenty of people leave the salon with their ends trimmed so their hair will grow faster. But the scissors never reach the place where that is decided.
Hair is formed in the follicle. What you see on the outside is dead keratin. Cutting it sends no signal to the root: hair grows about a centimetre a month, whether you trim it or not.
What does change is the end itself. If it is split, it frays. If it is healthy, the hair looks thicker. In 1928, the anatomist Mildred Trotter showed something similar with body hair: shaving it does not make it coarser or darker.
Pores don't open and close
It is an idea promoted by astringent toners. However, pores have no muscle that would allow them to open or close. Steam doesn't open them and cold water doesn't close them. Steam only softens sebum.
What makes pores larger is built-up sebum, genetics and the collagen lost with age and sun exposure.
A retinoid at night can make them less visible. It is best to start with a pea-sized amount, two nights a week. It causes irritation and makes skin more sensitive to the sun, so sunscreen is essential the next day. It should be avoided during pregnancy or when trying to conceive.
Oily skin needs moisturizer too
Sebum is oil; hydration is water. That is why the same face can be shiny on the forehead and feel tight on the cheeks.
Harsh or alcohol-based cleansers damage the skin barrier, and the skin loses more water. What works is a gentle cleanser morning and night, plus a light, non-comedogenic gel moisturizer.
If acne is severe or leaves scars, see a dermatologist.
A tan doesn't protect you from the sun
This is the hardest myth to let go of. A lasting tan develops once ultraviolet radiation has already damaged the DNA in your cells. It is a response to damage, not a shield. As a filter, it is estimated to be equivalent to a sun protection factor of between 2 and 4.
That damage builds up every summer until melanocytes start producing pigment unevenly. That is how sunspots appear. The ones that show up in your fifties started forming during the summers of your twenties.
How to protect yourself from the sun every day
Every morning, apply a sunscreen with SPF 30 or higher. The right amount is two finger-lengths of product for the face and neck.
Wear it in winter too, because ultraviolet A passes through clouds and glass. If you are out in the sun, reapply every two hours.
And if a mole changes shape, colour or size, see a dermatologist.
Frequently asked questions
Does trimming the ends make hair grow faster?
No. Hair grows about a centimetre a month from the follicle, and cutting it has no effect on the root; it only improves how the ends look.
Does cold water close your pores?
No. Pores have no muscle to open or close; steam only softens sebum, and cold water doesn't close them.
What moisturizer should I use if I have oily skin?
A light, non-comedogenic gel moisturizer, along with a gentle cleanser morning and night.
Does having a tan protect you from the sun?
No. A tan is a response to DNA damage and, as a filter, it is estimated to be equivalent to an SPF of only 2 to 4.
Informative article written with the help of AI tools from the verified script of the video. The video is in Spanish.