In the laboratory, caffeine can stimulate hair growth. There is insufficient research into whether hair products with caffeine can do this under real conditions.
Question: Can cosmetic products with caffeine for hair and scalp help against hereditary hair loss?
Answer: There is no scientific evidence.
Morning coffee wakes you up and stimulates the senses thanks to caffeine. So why not the hair too? After all, hair loss is widespread, especially among men. Because the cause of hereditary hair loss, also known as androgenetic alopecia, is the sex hormone testosterone.
Manufacturers of hair care products have also recognized that hair loss is a concern for many men and women. Shampoos, conditioners and tonics therefore advertise the activating effect of caffeine. It is said to stimulate the hair roots and make hair grow again. Because caffeine is supposed to act as an antagonist to testosterone at the hair roots.
But can hair products with caffeine really add more hair to the head in men and women? And in such a way that the effect can also be felt? Or are such promises – pardon me – drawn by the hair? We took a closer look at the study situation.
Theoretically possible, in practice poorly researched
Our search in three scientific databases uncovered several studies on the topic: on the one hand laboratory studies, on the other hand studies with male test subjects. However, this was not revealing.
The studies from the laboratory have shown that caffeine migrates through the scalp, then into the hair roots. However, it cannot automatically be concluded from this that it works there as promised by manufacturers.
We were able to find a total of six studies that investigated this question. Only men with hereditary hair loss took part in the studies.
We could not find studies on the effect in women. We also did not find any studies on the effects of caffeine on other forms of hair loss.
Not very trustworthy
All study teams reported less hair loss and greater satisfaction with hair care products with caffeine. The problem: All six studies have serious shortcomings and are therefore anything but trustworthy from our point of view (more on this in the section The studies in detail ).
Whether caffeine shampoo and Co. work in practice cannot be answered on the basis of these results. Although an effect is conceivable and theoretically possible – the available studies are too inadequate to assess it.
This is why caffeine is not found in medical guidelines for doctors: it does not appear there as a possible treatment for hereditary hair loss.
The main thing is hair
Hereditary hair loss is also called androgenetic alopecia in technical jargon. It’s a typically male phenomenon. In Europe, it affects around 8 in 10 men over 70 years of age and 4 in 10 women from the same age group.
Why do men have significantly more hair loss? This is due to the larger amounts of testosterone. The sex hormone can prevent hair from growing and accelerate hair loss. The hair roots become inactive over time. Typically, the hairline then begins to move upwards or the hair on the upper head becomes noticeably thinner.
In women too, too much testosterone can lead to increased hair loss. Around puberty or after menopause.
Hair loss can have many reasons
Hereditary hair loss is not a disease, does not pose a health risk and, strictly speaking, is “only” a cosmetic problem. But of course hair loss can be extremely stressful for those affected.
In addition to genetic androgenetic alopecia, there are other forms of hair loss. They can be the result of a disease: fungal infections of the scalp or autoimmune diseases, for example. Certain treatments can also cause hair loss as a side effect. This includes chemotherapy for cancer.
Caffeine kick for your hair?
With hereditary hair loss, caffeine is said to help with its anti-testosterone effect. Caffeine inhibits an enzyme (phosphodiesterase), which means that less testosterone is converted into its active form dihydrotestosterone.
Applied to the scalp, caffeine is supposed to migrate to the roots of the hair and provide less active testosterone there. And that means: longer growth phases, better blood flow to the hair roots and faster hair growth.
At least that’s the theory. The real benefits of washing your hair with caffeine shampoo and using other cosmetic products with caffeine is unclear, however.
Other drugs better researched
There are substances against hereditary hair loss whose effects have been much better researched than those of caffeine. Minoxidil (for application to the scalp) or finasteride (as a medicine to be swallowed) have been shown to inhibit the effects of testosterone. These drugs are effective and safe. This has already been shown in sufficiently reliable studies.
We took a closer look at what works against hereditary hair loss in an earlier article, see What helps against hair loss?.