Nutritional Approaches For Thinning Hair (2025)

Knowing your hair looks good is important for self-confidence, but your hair naturally tends to become finer as you get older. In some cases this hair thinning is genetic, but in others it can be linked with lack of certain nutrients – especially minerals. Thinning hair can also result from hormone imbalances, such as an underactive thyroid gland, polycystic ovary syndrome (PCOS), recently having a baby, or as a result of menopause.

How hair changes with age

You were born with between 100,000 to 150,000 hair follicles on your head – a number that remains relatively fixed throughout life.

Blondes tend to have more hairs than brunettes, but their hair is finer. Brunettes, in turn, have more follicles than red-heads, while brown hair tends to be thicker, which gives a fuller look. And, although men and women have a similar number of hair follicles, the male hormone, testosterone, acts on hair follicles to stimulate the production of hair that is thicker, longer and darker.

Whatever your sex and natural hair colour, the diameter of individual hairs naturally decreases after the age of 25 so that, by the age of 40, you have noticeably finer hair than when you were younger.

At the same time, more follicles stay in their resting phase, resulting in hair that becomes progressively thinner. Thinning is further accentuated by falling oestrogen levels around the time of the menopause, and by a lack of vitamin D, which leads to disordered hair cycles and hair loss.

Other nutritional deficiencies associated with thinning hair include a lack of iron, which affects an estimated one in four women, and low intakes of iodine which affect a further one in ten women.

How diet can help thinning hair

Although hair itself is a non-living structure, your hair follicles that produce and nourish each individual hair are very much alive. What’s more, the cells within your hair follicles are among the most active cells in your body.

Each of your hair follicles goes through repeated cycles of active hair growth (anagen) during which the hair lengthens, followed by a resting phase (catagen) in which the hair follicle shrinks and the bulb pulls away from the root. The hair then remains at a constant length until it loosens and falls out (telogen). Because each hair has its own cycle, you normally lose between 80 and 100 scalp hairs per day. If you lose more hair than you can replace then gradual thinning becomes increasingly noticeable, especially in later life when hair growth also slows.

After its resting phase, a hair follicle may reactivate to produce a new hair, but this cycle does not repeat indefinitely. On average, each follicle reactivates around 25 times before it switches off, or produces hair that is increasingly wispy and short.

To keep your hair cycles working at optimum efficiency, you need a constant supply of nutrients, such as amino acids (eg lysine), essential fatty acids, vitamins (eg vitamin C, vitamin B5, biotin, folate, vitamin D) and minerals (especially iron, iodine and zinc). Lack of vitamin D, for example, leads to disordered hair cycles and hair loss, while almost one in four women don’t get enough iron to replace menstrual losses so their hair suffers, too. A further one in ten don’t get enough iodine to maintain healthy hair growth.

Because hair follicles (and nail beds) are non-essential structures, these precious nutrients are diverted away from your scalp (and fingertips) in times of deficiency. This is achieved by constricting the tiny blood vessels that supply your hair so fewer nutrients are delivered. The result, as well as thinning hair, is hair that is dry and lack-lustre, too.

That’s why hair is a good indicator of your general health and is often the first part of the body to show signs of nutritional deficiency or ill-health. You may see signs of deficiency in your nails, in the form of horizontal ridges. In your hair, the same underlying causes can show up in the form of thinning hair.

Protein is vital

Your hair mostly consists of keratin protein, which is produced using amino acids that are mostly derived from the protein in your diet.

Your hair follicles need a constant supply of protein, so eat a protein source with every meal, whether it’s poultry, lean meat, fish, eggs, nuts or beans.

If you eat a plant-based diet, you are more prone to thinning hair as some amino acids essential for healthy hair (such as lysine) and micronutrients (such as vitamin B12 and iron) are often difficult to obtain in sufficient quantities without taking a vegetarian/vegan supplement.

Don’t skip meals, as this will restrict your supply of protein and nutrients, putting your body on red alert so that nutrients are diverted away from hair follicles.

Increase your intake of plant hormones

Isoflavones are plant hormones with a weak, oestrogen-like action, and which provide a useful oestrogen boost when your hair is hair thinning due to a hormone imbalance such as PCOS, after pregnancy, or due to menopause. Isoflavones are mainly found in edamame beans and other soy products.

In Japan, where soy is a dietary staple in the form of tofu, miso and edamame beans, for example, intakes of isoflavones are 50mg to 100mg per day for both men and women, compared with typical western intakes of just 2mg to 5mg isoflavones per day. Blood levels of isoflavones in Japan are therefore as much as 110 times higher than those typically found in the West. This is one possible explanation for why Asian women who follow a traditional diet tend not to experience thinning hair, and while Asian males tend to experience hair loss a decade later than European males.

These plant hormones also have beneficial effects against benign prostate enlargement in later life.

Lignans are another type of plant oestrogen which have the additional advantage of inhibiting the enzyme, 5-alpha-reductase, which converts testosterone to DHT in scalp follicles. DHT is one of the main hormone factors that switch off hair follicles in males, and in women with PCOS or as the menopause approaches.

High intakes of lignans, which are found in pumpkin seeds, ground flax seeds and sweet potato, may help to reduce hair thinning. Pilot studies suggest that lignan supplements may improve hair loss after one to two months, as well as decreasing scalp oil secretion. Given how wide-spread the problem is, it’s surprising that researchers haven’t explored this possibility further.

Another important nutritional approach is to cut back on salt intake which, according to trichologists, can lessen hair loss by as much as 60 per cent (as well as having beneficial effects on blood pressure).

While diet should always come first, a multivitamin and mineral supplement is a good idea – especially if you are cutting back on food intake to lose weight.

Supplements for thinning hair

Numerous supplements are available to help boost hair growth. Most contain a blend of ingredients that are also beneficial for skin and nails. These include biotin, protein such as collagen, a silica source, such as horsetail (a type of plant), plus antioxidants to protect hair follicles from premature ageing.

	Perfectil Plus, Hair Extra Support contains 200mg marine collagen, 200mg horsetail botanical extract, amino acids, co-enzyme Q10 plus key vitamins and minerals, at boosted doses. Check price at Amazon.co.uk and at Amazon.com.
	Solgar Skin, Nails & Hair Advanced MSM Formula supplies silica, amino acids, MSM (a sulfur source to help strengthen hair fibres) plus vitamin C, zinc and copper. Check price at Amazon.co.uk and at Amazon.com.
	HairAnew contains 11 nutrients to improve hair growth, including biotin and other vitamins, zinc, kelp (an iodine source), Ginkgo biloba (to increase blood flow to the scalp), and silica from bamboo. It is one of the best-selling supplements, provides a certificate of purity, and is one I strongly recommend. Check price at Amazon.co.uk and at Amazon.com.
	Zhou HairFluence is a premium hair growth supplement that provides 11 vitamins, calcium, MS, Bamboo leaf extra (for silica), plus protein in the form of 400mg collagen hydrolysate and 50mg hydrolysed keratin. Check price at Amazon.co.uk and on Amazon.com.

What About Caffeine Shampoos?

Caffeine shampoos are helpful for both men and women with thinning hair. The caffeine must penetrate directly into hair follicles to stimulate hair growth, so drinking tea or coffee will not help.

Caffeine shampoos work by relaxing the smooth muscle fibres surrounding hair follicles so that delivery of blood, oxygen and nutrients improves. Caffeine applied topically also inhibits an enzyme, 5-α-reductase, which converts testosterone into dihydrotestosterone (DHT) within scalp hair follicles – a hormone which switches off scalp follicles and is associated with both male and female pattern hair loss.

Even at low concentrations, caffeine inhibits the effects of DHT to stimulate hair follicle growth. When applied as a shampoo, just two minutes contact with the scalp allows the caffeine to penetrate deeply, where it remains for up to 48 hours, even after hair washing. A leave-on caffeine combination that also included vitamins B3 and B5 has been shown to increase the cross-sectional area of scalp hair fibres by 10% to produce noticeable thickening.

	I started using Dr Wolff’s Plantur 39 shampoo and conditioner around a year ago and have noticed a significant improvement in the thickness and strength of my hair. There is also a caffeine tonic for direct application to the scalp as an additional treatment. Check prices and buy from Amazon.co.uk and from Amazon.com
	Alpecin is a similar range of shampoo and tonic for men, which is also from Dr Wolff. The range includes shampoos for dandruff (Double Effect) and to help maintain normal hair pigmentation (Tuning Shampoo). Check prices and buy from Amazon.co.uk and from Amazon.com

Click here for my Expert Health Review of caffeine shampoos for women and men.

Have you found caffeine shampoos or any nutritional approaches helpful?

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