Nutritional Approaches For Thinning Hair

thinning hair

Knowing your hair looks good is important for self-confidence, but it’s common – even normal – for hair to become finer and more sparse with age. You were born with between 100,000 to 150,000 hair follicles on your head – a number that remains fixed throughout life. Blondes tend to have more hairs than brunettes, but their hair is finer. Brunettes, in turn, have more follicles than redheads and brown hair also 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.

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.

What About Caffeine Shampoos?

Caffeinated shampoos are helpful for both men and women with thinning hair. Unfortunately, drinking caffeine in coffee, or even green tea, will not have the same effect – the caffeine must penetrate directly into hair follicles to stimulate hair growth.

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 around a year ago and have noticed a significant improvement in the thickness and strength of my hair.

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

Plant-Based Hormones May Help

Isoflavones are plant hormones with a weak, oestrogen-like action, and which provide a useful oestrogen boost for women whose hair thinning is related to the menopause. Isoflavones are mainly found in edamame beans and other soy products.

In Japan, where soy is a dietary staple, 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 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.


To achieve significant isoflavone intakes for treating thinning hair, select a non-GMO soy isoflavone supplement supplying between 40mg and 100mg isoflavones per day.

SOYI120Healthspan’s Soy Isoflavones are made to pharmaceutical standard and provide 100mg soy extract providing 40mg isoflavones. Check price from

A similar quality product in the US is Best Naturals’ Soy Isoflavones

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Life Extension Super Absorbable Soy Isoflavones provides 54mg isoflavones per capsule, of which 28mg is in the beneficial genistein form.

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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.

High intakes of lignans (found in pumpkin seeds, ground flaxseed and sweet potato) may therefore 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).

Have you found caffeine shampoos or any nutritional approaches helpful?

Photo image: ryan_mcguire/pixabay

About DrSarahBrewer

Dr Sarah Brewer MSc (Nutr Med), MA (Cantab), MB, BChir, RNutr, MBANT qualified from Cambridge University with degrees in Natural Sciences, Medicine and Surgery. After working in general practice, she gained a Master's degree in Nutritional Medicine from the University of Surrey. Sarah is a licensed Medical Doctor, a Registered Nutritionist, a Registered Nutritional Therapist and the award winning author of over 60 popular self-help books. Sarah's other websites are and

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