How hormone fluctuations can cause hair thinning and loss — and what you can do about it

I have a tangled relationship with my hair. When I was younger, all I had to do with my long curls was wash them regularly, and they did what I asked.

I’ve cut my hair shorter as I’ve got older, but it’s far drier than it once was. It’s not as thick and, despite efforts to convince myself otherwise, it’s turning grey.

I’m out of step with the trend for big hair — check out Sabrina Carpenter’s blonde, bouncy tresses.

Trichologist Carol Johnson, who runs the Universal Hair and Scalp Clinic in Dublin (@trichologisthelp), says that age and hair quality are inextricably linked. Carpenter is in her mid-20s, I’m in my mid-40s. And, whether I like it or not, my hair is ageing along with the rest of me.

Our hair goes through two main stages. “Firstly, our hair spends six to eight years in its growth phase over the course of our lives, which isn’t long in the context of the human lifespan,” says Johnson.

“A lot of this growth happens when we’re younger, which explains why hair tends to become thinner with age.”

Then, fluctuating hormone levels in midlife undermine hair growth. “Falling levels of oestrogen in women can result in hair thinning and loss,” says Johnson. “And changing testosterone levels are a contributory factor in hair loss in men and women.”

Dr Des Tobin, professor of dermatological science at University College Dublin, says we produce less sebum as we age, which is another factor that negatively impacts the look of our hair.

“Sebum is nature’s conditioner,” he says. “It’s an oily substance produced by a small gland attached to the hair follicle that acts as a lubricant and helps seal in moisture. A reduction in sebum can cause hair to become more fragile and brittle, which means it’s more easily damaged. It also leaves it lacking lustre.”

Stress also affects the condition of our hair. “It causes the hormone cortisol to seep into the hair shaft and interrupt the growth phase of hair,” says Johnson.

“When I carry out blood tests on clients who complain of hair and scalp issues, their cortisol levels are often high.”

Hormonal factors

My oestrogen levels are likely declining. My hair is coarser than it used to be, so my sebum production appears to have reduced. I’m often stressed: I struggle to balance work and family life. Am I doomed to never-ending bad hair days?

Not necessarily, according to our experts, who have tips on how to keep hair healthy as we age.

“Generally, hair is robust and resilient,” says Tobin. “And it grows in cycles, so it can be renewed, even if we damage it.”

Hair dye, for example, usually contains ammonia, which has a drying effect.

“Ammonia allows colour to penetrate the hair cuticle, but the more you use it, the more it dries out your hair,” says Johnson.

Her advice is not to dye hair too frequently. “So what if you can see your roots,” she says. “There are powders you can apply to cover them up.”

If you wear hair extensions, take breaks from wearing them. “Otherwise, repeatedly weighing down the ends of your hair will cause pulling, which could result in problems like traction alopecia.”

We should also beware of overusing heated tools, like tongs, straighteners and dryers, as they remove moisture. “They can reach temperatures of 180ºC,” says Tobin. “That can cook our hair.”

Johnson’s hair-care regimen is simple: Brush your locks morning and night. And don’t forget to brush your scalp, too, as doing so will boost blood flow, which encourages hair growth.

When it comes to choosing a hairbrush, Johnson’s advice is equally straightforward. “Choose a splayed brush, where the prongs are spread apart, and press it against the palm of your hand,” she says. “If it doesn’t hurt, it’s a good brush.”

However, she warns against brushing hair when wet, as this can make it more vulnerable to breaking. If your hair needs detangling, use a wide-toothed comb.

The right shampoo

What about the overwhelming array of hair products on the market? Tobin believes some are useful: “They can compensate for the loss of natural sebum and may help reduce breakage.”

With so many to choose from, Johnson urges us to focus on the basics: “Find the right shampoo. Most of us should wash our hair between three and five times weekly with a shampoo that contains glycerine, an ingredient that keeps hair hydrated.”

She says people who don’t colour their hair and have a healthy amount of sebum don’t always need conditioner. 

“Or they may only need to apply it to the ends of their hair,” she says. “I like conditioners with natural ingredients, like coconut, but remember that the best conditioners are those provided by the foods you eat. So try to eat lots of good fats in the form of oily fish, nuts and seeds.”

She can see how products like scalp-stimulating brushes might boost blood flow and encourage hair growth, but she doesn’t necessarily recommend we buy them: “Instead, you can place the palms of your hands on your head and, using the fleshy pads at the base of your palms, you can apply pressure and make little circular movements to massage your scalp.”

“This will invigorate oxygenated haemoglobin, which is the elixir of growth. It will also relax you, bringing down those stress hormones.”

Paying attention to the water we use to wash our hair might be more effective than splurging on products. “Hard water builds up in kettles and on our hair, too, parching it in the process,” says Johnson. “Fitting a filter should make a difference.”

Her mantra is to keep things simple. “Give your hair a break from colours and treatments. Have days when you don’t wash it. Cut it regularly to get rid of split ends.”

“Eat well. Get enough sleep. Manage your stress and see what that does to your hair.”

That’s what I’m doing. I no longer brush my hair when wet. I’ve ordered silk pillowcases and started massaging my scalp while watching TV. Will it mean the end of bad hair days? Here’s hoping.

A diet of B vitamins and proteins can strengthen hair

Dietitian Aveen Bannon, who leads the Dublin Nutrition Clinic, emphasises the importance of diet. For her, it starts with water for hydration.

“Then, because hair is made from a protein called keratin, we should ensure we get enough dietary protein from foods like meat, fish, eggs, tofu and diary,” she says.

“The B vitamins niacin, pantothenic acid and pyridoxine are thought to play a role in strengthening hair. And the B vitamins folic acid and biotin are needed to stimulate new growth. You’ll find these vitamins in meat, fish, poultry dairy, eggs, fortified breakfast cereals, legumes, nuts, leafy greens and nutritional yeast.”

Low iron levels are associated with hair loss, so Bannon encourages us to eat lean, red meat, green leafy vegetables, beans, and pulses.

Zinc, which is found in meat, fish, nuts, and dairy, can also promote hair growth. Generally, hair is robust and resilient and it grows in cycles, so it can be renewed, even if we damage it.