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Is Sunlight Good for Your Hair? Evidence Review 2023
Dr Ahmad Moussa (FRCS)
Medically reviewed by
Dr Ahmad Moussa (FRCS)
Updated on May 13, 2024

It can be lovely to feel warm rays upon your tresses, but is sunlight good for your hair? You may know that exposure to the sun is needed to get a natural dose of vitamin D, which is good for your immunity, bones, and skin. Moreover, there is some scientific indication that insufficient levels of vitamin D may contribute to hair loss [1]. 

However, numerous studies have revealed that prolonged exposure to the sun can cause significant damage to your locks, ranging from summer hair loss, to dry, brittle hair which breaks off easily, hair ageing and discolouration. 

So while it is a good idea to spend some time in the sun to get your necessary 15 micrograms of vitamin D per day [2], it is best to protect your hair from UV radiation while doing so.

Keep reading this article to find out more about:

  • The effects of sunlight on your hair
  • The relationship between sunlight and hair loss
  • The necessary amount of exposure to sunlight for your hair health
  • Ways to prevent hair damage from exposure to hair loss
Table of Contents

Is sunlight good for your hair?

Sunlight is the best of the few natural sources of vitamin D. Studies show a correlation between insufficient levels of this vitamin and hair loss [3]. Moreover, if you are experiencing conditions such as scalp psoriasis, UV light therapy (phototherapy) has been found to be beneficial [11].

So it is understandable to think that exposing your hair to the sun can prevent hair shedding or lead to better scalp and hair health. 

However, that would not be accurate, as overexposing your tresses to UV radiation can also cause them significant harm.

How can sunlight damage your hair?

Research shows that excessive exposure to the sun can damage your hair in a number of ways [4][5][6][7]:


The main types of damage caused by excessive exposure to sunlight
It can cause dry scalp and hair [4]The drying out of moisture from your scalp and hair can lead to dry, dull, frizzy tresses which break off easily and feel rough to the touch
It can cause photodegradation of the hair cuticles [5]Prolonged exposure to UV radiation can make microscopic cavities in the hair cuticles and make them lift or even detach, leaving your hair fragile, prone to breaking off and getting split ends instead of healthy hair.
It can alter the colour of your hair [8][4]The oxidation of hair pigments can also result in an altered hair colour, especially in grey or light-coloured hair. Thus, darker shades, such as brunette, may get a reddish hue, while lighter ones, such as blonde or grey, will often experience yellowing.
It can cause photoaging [6]The photochemical degradation of hair protein and pigments makes your hair fibre porous, brittle and prone to hair breakage, as well as increasing strand roughness.
It can worsen the symptoms of common scalp problems in people experiencing hair loss [7]

Prolonged exposure to UV radiation can worsen the symptoms of:


It may play a role in exacerbating conditions which cause hair loss [7]


If you are experiencing worsening symptoms of your scalp problems or accentuated hair loss after being out in the sun for a long time, be sure to contact a trichologist.

This is especially true if you are already experiencing a condition which causes progressive hair loss, such as androgenetic alopecia. That is because your condition can progress to the point where it cannot be treated with medication alone and may require a hair transplant.

Who can get hair damage from excessive exposure to sunlight?

While anyone can experience negative hair and scalp consequences of overexposure to sunlight, it is usually people with grey or light-coloured hair who are at the highest risk. That is because light-coloured hair is more sensitive to light than darker shades, due to the extra protection provided by the higher levels of melatonin in dark hair (the pigment which colours your skin and hair). 

However, while higher amounts of melatonin may offer some additional protection to the inner layers of your hair fibre, its outer protective layer – the cuticle – can receive similar amounts of damage from UV radiation in all hair colours [5].

Does the sun make your hair look better?

Since excessive exposure to sunlight has been found to make your hair frizzy, lacklustre and straw-like, as well as prone to split ends, it is safe to say that the sun is unlikely to make your hair look better. 

While light shining on healthy, well-cared-for hair can appear to increase its brilliance, the structural damage experienced by the hair fibre when exposed to UV radiation is more likely to reduce its natural beauty than enhance it. 

Moreover, while some people with darker shades of hair might appreciate a bit of sun bleaching, those with lighter shades might find the yellowing of their hair colour unappealing.

yellowing gray hair
Yellowing on grey hair

Does the sun help damaged hair?

If your hair is already damaged, exposing it to the sun will not help it, but is more likely to harm it further. As previously discussed, UV radiation is likely to weaken your hair strand, attacking its natural protection, photoaging it and making it more prone to breaking. 

So, if you are experiencing damaged hair and would like to spend some time in the sun, it is a good idea to protect your hair by covering it up with a large brimmed hat or a headdress. Using UV protection on your hair may also be helpful, although more research is needed to determine its efficiency and the kind of formula which works best on the human scalp, which has far greater hair coverage than your skin [5].

If you are looking for solutions to treat and repair damaged hair at home, you can try moisturising hair masks, trimming your split ends regularly and avoiding heat styling and overuse of hair products which contain harsh chemicals. 

dry hair ends

How much sunlight does your hair need a day?

Your hair does not need direct exposure to sunlight, but you do need sufficient levels of vitamin D in your system. This can be obtained directly from the sun, in the form of supplements, or by eating a vitamin D-rich diet (oily fish such as salmon or mackerel, egg yolks and liver) and fortified foods (e.g. some cereal, plant milks, or fat spreads).

Ideally, every adult needs to get 15 micrograms of vitamin D each day. If sunlight is the only source for getting it, the amount of time you need to spend in the sun to achieve the daily recommended dosage depends on the proportion of your body that is exposed to the light and the season and climate at your location. 

Thus, a few minutes of 25% body exposure can be sufficient in the summer in a region with a warm climate, while as long as a couple of hours might be necessary in winter in a colder climate, where the amount of body exposure would also go down to around 10% [9].

Keep in mind that your hair and scalp do not need to be directly exposed to sunlight to get the benefits of vitamin D, it works just as well if it is absorbed through your skin. So do not hesitate to cover your hair in hot weather, to protect it from sun damage.

However, please be aware that while wearing sunscreen can reduce UV absorption, it is a good idea to limit unprotected skin exposure to the sun on hot days, in accordance with the UV index provided by your local weather forecast and your skin sensitivity. 

Can lack of sunlight cause hair loss?

Lack of sunlight itself does not cause hair loss, but the lack of vitamin D, which is mostly obtained from the sun, can accelerate your hair shedding. It is commonly thought that vitamin deficiencies cause hair loss, but what they really do is accelerate the hair loss you are already experiencing.

Some studies have found a correlation between vitamin D deficiency and excessive hair shedding, as a significantly higher number of people with telogen effluvium or androgenetic alopecia showed insufficient vitamin D levels [3][10].

However, there is no indication that an increased vitamin D intake would play any role in stopping or reversing hair loss, though it may help prevent additional hair shedding.

There is also an indication that low levels of vitamin D may play a role in the development of hair loss-inducing conditions such as alopecia areata. That is because it is an autoimmune condition and vitamin D plays a role in regulating the immune system [3]. 

micronutrient level changes observed in people with alopecia areata
Micronutrient level changes observed in people with male pattern baldness
Micronutrient level changes observed in people with male pattern baldness
Micronutrient level changes observed in people with female pattern baldness
Micronutrient level changes observed in people with female pattern baldness

How to prevent sun damage to your hair

There are several things you can do to prevent sunlight from damaging your hair:

  • Keep your hair conditioned and moisturised at all times
  • Cover your hair when you plan to spend a long time under the hot sun
  • Use shampoos with UV protection (you can find some among the best and worst shampoos for hair loss)
  • Eat a healthy diet, rich in the best vitamins for hair growth
  • Enhance your vitamin D intake with supplements or fortified foods
  • Some studies suggest hair dye might play a protective role against UV radiation [7], but be aware that excessive use of dye can cause hair loss 
woman in the sun

Are you concerned about sun-damaged hair?

If you are concerned that your hair has been damaged by overexposure to the sun, it is best to get it checked out before you start experiencing hair loss. And if you are already losing your hair, it is important to see a hair specialist as soon as possible, before the condition which is causing it has a chance to progress.

So for your peace of mind, book a consultation now with one of our top trichologists, at your most convenient clinic location. They will take a close look at your tresses and let you know the probable cause and extent of any damage. And they will also provide the best advice and treatment, in accordance with their findings, so your hair will be happy and healthy once more.

Is Sunlight Good for Your Hair? Evidence Review 2023, Wimpole Clinic

Dr Ahmad Moussa (FRCS)
Medically reviewed by Dr Ahmad Moussa (FRCS)Updated on May 13, 2024
The Wimpole Clinic offers FUE Hair, Beard & Eyebrow Transplants & Trichology.
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