Can Aspirin Stop Hair Loss?

Could it really be that simple? Aspirin, one of oldest and most widely available medicines, may hold the key to stopping hair loss. We know it’s helpful for reducing inflammation – a common side effect of male pattern hair loss – but it also fits with recent breakthroughs in hair loss research. So, can aspirin stop hair loss?

Aspirin and hair loss

Aspirin (acetylsalicylic acid) has been used as a form of medication for thousands of years – in the form of leaves from the willow tree.

In the late 19th century, aspirin was synthesised by chemists. Today, it’s one of the most widely used medications – used to treat pain, inflammation, fever, as well as prevent heart attacks and strokes.

There’s even evidence to suggest it may reduce the risk of certain types of cancer.

But can we add hair loss to the list of conditions treatable with this wonder drug?

Inflammation

It is well established that aspirin has anti-inflammatory properties.

And inflammation is a common symptom of male pattern hair loss. Some studies even go as far as to suggest it is the cause.

But even if this correlation is pure coincidence, aspirin is likely to be beneficial in reducing scalp microinflammation. This may reduce the redness and itchiness that so often accompanies pattern hair loss.

The link between aspirin and hair loss goes deeper than just the inflammation connection, though.

PGD2 and hair loss

Currently, the popular medical consensus is that male pattern hair loss is caused by the hormone dihydrotestosterone (DHT).

This explains why pattern hair loss tends to affect men more than women – men have higher levels of this hormone.

But there are a number of problems with the theory that DHT causes hair loss.

In 2012, a pioneering medical paper proposed an alternative account of hair loss: prostaglandins. Specifically, prostaglandin D2 (PGD2).

The key findings of the study were:

PGD2 levels are around 3x higher in balding scalps compared to non-balding scalps.
Increasing PGD2 in mice causes follicular miniaturisation and sebaceous gland hyperplasia – in other words, male pattern hair loss.

You can find out more about the PGD2 hair loss study here.

Since 2012, the connection between prostaglandin D2 activity and hair loss has only been strengthened.

For example, it has been observed that castration greatly reduces the expression of PGD2^1,2,3. This explains why drugs that reduce DHT levels – such as finasteride – make for effective hair loss treatments. Reduced DHT has the knock-on effect of reduced PGD2 – but it’s not DHT itself that causes hair loss.

PGD2 almost certainly plays a major role in the development of androgenetic alopecia (male and female pattern hair loss). This is where aspirin comes in.

Aspirin and prostaglandins

So, increased PGD2 activity leads to hair loss.

And aspirin has been demonstrated to inhibit the formation of prostaglandins such as PGD2.

So, it seems plausible that aspirin could effectively slow or stop hair loss by reducing PGD2 levels in the scalp.

Unfortunately, it’s not that simple.

The 2012 study also made another observation: another prostaglandin – PGE2 – is actually lower in bald scalps.

So, men with pattern hair loss have higher levels of PGD2 but lower levels of PGE2 in their scalps.

Ideally, then, an effective prostaglandin-based hair loss treatment would lower PGD2 but increase PGE2.

But aspirin works by lowering all prostaglandin activity – not just PGD2. So, the positive effects of reduced PGD2 may be offset by the negative effects of reduced PGE2.

As this study notes:

“Prostaglandins typically control bodily functions in a “yin and yang” manner where they have opposing functions […] In the case of hair, it is known that PGE₂ and PGF₂a stimulate hair growth, while PGD₂ inhibits hair growth”

Nevertheless, this infomation is still cause to be positive. If nothing else, it can be put toward developing new and more effective hair loss treatments – ideally without such devastating side effects as DHT inhibitors.

Aspirin and minoxidil?

Minoxidil is one of only two FDA approved hair loss treatments – the other one being finasteride (Propecia).

Unlike finasteride, though, it’s still a bit of a mystery how minoxidil actually works – but we know it’s got nothing to do with reduced DHT.

Somewhat strangely, DHT is known to cause facial hair to get thicker even though it appears to make hair on the scalp thinner. So, a hair loss treatment that worked by reducing DHT should, in theory, reduce facial hair.

Minoxidil actually increases beard growth, however.

Not only that, it’s been demonstrated to have no effect on scalp DHT – even though it makes scalp hair thicker. So, minoxidil must work via some other method.

It’s not proven, but it has been speculated that minoxidil works by increasing PGE2^1,2,3 – the good prostaglandin.

It’s entirely speculative, of course, but the combination of aspirin – to reduce PGD2 – and minoxidil – to increase PGE2 – could create the favourable balance of prostaglandins necessary to stop hair loss.

For now, though, it’s probably best to leave it to the scientists to develop a more elegant solution!