How to get thicker hair: what you can and can’t change

What decides how thick your hair is?

“Thick hair” means two different things, and both are largely inherited:

• Density – how many hairs grow on your scalp. You are born with all the hair follicles you will ever have.
• Strand thickness – how wide each individual hair is. Fine, medium and coarse hair are mostly genetic, and vary with ethnicity.

Hormones then shape how that plays out over time. In people prone to pattern hair loss, follicles gradually shrink and produce finer, shorter hairs – which is why hair can look thinner with age, after the menopause or with conditions such as polycystic ovary syndrome. No shampoo, oil or food can change your genes, so the honest goal is to keep the hair you have in good condition and to rule out anything treatable.

Can thin hair become thick again?

It depends on why it thinned. If the cause is temporary – shedding after an illness, a stressful event, childbirth, a crash diet or iron deficiency – hair usually grows back once the trigger has passed or been treated, although it can take six months or more to look fuller again.

If hair has thinned because of pattern hair loss, it tends to progress slowly over years. Medical treatments can slow it down and in some people partly reverse it, but only while you keep using them. That’s a conversation for a GP, pharmacist or dermatologist.

How can I make my hair thicker naturally?

You can’t add follicles, but you can stop losing length and volume to breakage, and make the hair you have look fuller:

• Be gentle when it’s wet. Wet hair stretches and snaps more easily. Blot with a towel rather than rubbing, and use a wide-tooth comb.
• Turn the heat down. Straighteners, curling tongs and very hot hairdryers damage the hair’s outer layer. Use a lower setting and a heat protectant, and give your hair days off.
• Go easy on chemical treatments. Bleaching, perms and relaxers weaken the hair shaft, especially when repeated or overlapped.
• Loosen tight styles. Tight ponytails, buns, braids and extensions pull on the follicles. Over time this can cause traction alopecia – hair loss that can become permanent.
• Keep the scalp healthy. Treat dandruff or an itchy, flaky scalp, which can make you scratch and break hairs.
• Get regular trims. Cutting doesn’t make hair grow faster, but removing split ends stops them travelling up the shaft and makes the ends look fuller.

How can you make hair look thicker?

Styling won’t change your hair, but it can change how much of it you appear to have:

• A blunt cut or a shorter length often looks fuller than long, layered hair, which can look thin at the ends.
• Lightweight volumising products, dry shampoo at the roots and blow-drying upside down add lift.
• Moving your parting or changing hair colour slightly can disguise a widening parting.
• Heavy conditioners and oils can weigh fine hair down – use them on the ends rather than the roots.

What foods make your hair thicker?

No food makes hair thicker than your genes allow. What diet can do is make sure your follicles aren’t short of anything – and a real deficiency can cause shedding. The basics:

• Enough protein – hair is made of protein. Meat, fish, eggs, dairy, pulses, tofu and nuts all count.
• Iron – red meat, pulses, dark green vegetables and fortified cereals. Iron deficiency is a recognised cause of temporary hair loss, especially in women with heavy periods.
• A varied diet overall – rather than relying on a single “superfood”.
• No crash diets – rapid weight loss is a common trigger for shedding a few months later.

Which nutrients have a recognised role in normal hair, and which deficiencies a GP may test for, is covered in Vitamins for hair.

Does stress or lack of sleep make hair thinner?

A major physical or emotional shock – a serious illness, surgery, bereavement, a very stressful period – can push many hairs into the resting phase at once. About three months later, they shed together. This is called telogen effluvium. It looks alarming, but it usually settles on its own within about six months, and the hair grows back.

Everyday stress and the odd bad night’s sleep aren’t known to thin hair directly, but looking after sleep, stress and general health supports the rest of your body – your scalp included.

When should thinning hair be checked by a doctor?

See your GP if:

• you are suddenly losing a lot more hair than usual, or it comes out in clumps
• you have bald patches, or a scalp that is red, sore, scaly or scarred
• your parting is widening or your scalp is becoming more visible
• you also feel tired, cold, breathless or have heavy periods – which can point to thyroid problems or iron deficiency
• it started after having a baby, stopping or starting a medicine, or the menopause, and you are worried

Medical treatments such as minoxidil may help some types of hair loss, but they aren’t right for everyone and only work while used. Ask a GP or pharmacist before starting one. For more on causes and tests, see Hair loss in women.