Long, bright summer days of a traditional Kiwi summer are upon us. Sunshine boosts our mood, warms our skin, and encourages us to get outside and enjoy everything from bushwalks to backyard barbecues. For people living with multiple sclerosis (MS) the sun can still offer these benefits, but because MS interacts with heat and certain medications in unique ways it’s worth taking a thoughtful sun smart approach.
The benefits of sunshine.
Spending time in natural light is genuinely uplifting. Sunshine activates mood enhancing pathways, including the release of endorphins, which help create a sense of calm and wellbeing. It also prompts the skin to produce vitamin D, essential for bone strength, immune balance, and overall health which is especially important for people living with MS.
But vitamin D is only one piece of the puzzle. Research shows that sunlight also:
- Supports immune regulation by reducing inflammation and increasing regulatory immune cells, mechanisms linked with lower MS activity in observational studies (supported by wider immunology research).
- Benefits cardiovascular health, several studies have shown, by triggering the release of nitric oxide from the skin natural light helps lower blood pressure and improve vascular function.
- Influences brain and cognitive pathways, with UV exposure activating molecular signals that interact with the nervous system, potentially contributing to clearer thinking and better mood.
- Boosts general wellbeing, with sunlight tied to improved sleep patterns, seasonal energy rhythms, and resilience against some chronic diseases.
Taken together, these processes help explain why moderate, sensible sun exposure can be both energising and restorative, supporting physical, emotional, and neurological health in ways that extend well beyond vitamin D alone. As detailed here.
Balancing sunshine with safety.
It’s well known that we need to exercise caution in Aotearoa when it comes to sun exposure. Our summer UV levels are some of the highest in the world, which means burn times can be short, and the risks of UV damage to skin and eyes is increased. It is essential for everyone in New Zealand to take protective steps when enjoying the benefits of being outside in summer.
For people living with MS, there are extra factors worth keeping in mind. Heat can temporarily worsen MS symptoms for some individuals, making it harder to regulate body temperature and maintain energy levels on hot or humid days. In addition, certain MS medications may increase sun sensitivity or heat intolerance. Because of this, it’s helpful to understand how sunshine, heat, and medications can interact and to plan ahead so you can still enjoy the outdoors comfortably and safely.
MS and heat.
Heat sensitivity is common for people with MS. A small rise in body temperature can temporarily worsen symptoms because heat slows nerve conduction and can increase the impact of already damaged nerves.
People with MS may notice:
- Increased fatigue
- Blurred or hazy vision
- Weakness or heaviness
- Tingling sensations
The good news is these symptoms should ease within an hour of cooling down.
Tips to stay cool and comfortable:
- Seek shade, especially from 10am to 2pm, when the UV levels are at their highest and heat builds quickly.
- Use cooling tools – misting sprays, cooling scarves, iced water bottles, and personal fans.
- Wear breathable and light clothing to help keep your temperature stable.
- Drink water frequently throughout the day. Dehydration makes heat-related symptoms worse.
For more information see our article on enjoying a comfortable summer with MS and our temperature sensitivity page. SunSmart New Zealand also emphasise the importance of planning your time outdoors around the UV index which can be checked online or with UVI alert tools. See their website for more information and other useful resources.
Medication and sun exposure.
Some MS medications, particularly those that adjust the immune system, have implications for sun exposure.
Fingolimod (Gilenya) and melanoma monitoring.
Fingolimod is used widely in Aotearoa for relapsing MS. Because it alters immune response researchers have examined whether it may affect the body’s ability to detect and respond to early cancer cells. Clinical trials and safety reviews have reported a small number of melanoma cases among people taking fingolimod. For example, seven skin cancers (including two melanomas) were observed in early phase studies, and later trials continued to record occasional melanoma cases.
This does not mean people should avoid sunlight altogether, nor that fingolimod causes melanoma, rather that sensible precautions are recommended because immune-modifying medicines can reduce skin cancer surveillance in some people. You can read more in this study.
People taking fingolimod are encouraged to follow sun safety measures, important for everyone in Aotearoa’s high UV environment, and to have regular full skin checks with their GP or dermatologist. This approach supports early detection and allows people to continue benefiting from fingolimod while managing their skin health proactively.
Photosensitivity from medications.
Some medicines commonly used for managing MS symptoms, treating infections, or addressing other health conditions can increase the skin’s sensitivity to sunlight. This is known as photosensitivity, where UV light triggers a stronger-than-normal skin reaction. It can cause skin to burn more quickly than expected, or lead to redness, rashes, or blistering after even brief sun exposure. Both topical products and oral medications can cause these reactions, and they may appear within minutes or hours (phototoxic reactions) or even days later (photoallergic reactions). For more information about medications and photosensitivity see the Healthify page, or speak with your pharmacist.
Tips for managing medication and sun exposure.
Understand the medications you are on and what additional precautions you need to take. Ask your neurologist, MS nurse, GP, or pharmacist:
- Does my medication affect sun or skin cancer risk?
- Do any of my medications cause photosensitivity?
Ask your healthcare provider about skin checks, see Melanoma NZ for more information about skin checks and where these can be provided.
In summary
Staying well with MS during the summer months is all about the balance between enjoying the benefits of sunshine while taking practical steps to manage heat sensitivity and protect your skin. Sunshine can boost mood and support vitamin D levels, but Aotearoa’s high UV environment means being extra sun smart is essential.
Heat can temporarily worsen MS symptoms – planning with cooling strategies, hydration, shade, and breathable clothing makes a real difference to comfort and wellbeing.
Being aware that some medications can influence how your skin or body responds to the sun is important – taking general precautions and staying informed supports safer time outdoors.
Overall, a thoughtful, sunsafe approach allows people with MS to continue enjoying the outdoors while minimising discomfort and risk supporting a healthier, happier summer season.
External Resources to download
The resources below have been provided by Te Whatu Ora, along with this link for further reading.
Social Tile:
Posters & Brochure:
HNZ Summer Look after yourself in the heat
HNZ Summer Heat safety DL brochure