Health Advice

Sunscreen, sunblock, SPF: the sun protection skincare has been hailed by derms as the holy grail in skincare for ages. The reason? The sun is a potent skin ager, creates wrinkles, damages skin, and increases hyperpigmentation. By rigorously applying sunscreen every day, experts teach, we prevent or mitigate these effects. Recently, though, social media has been abuzz with concern about SPF,  with some calling sunscreen a scam or claiming formulations include toxic chemicals. We spoke to dermatologists about the biggest claims about sunscreen protection.Meet the experts: Dr Tarryn Jacobs is a specialist dermatologist at Life Eugene Marais hospital in Pretoria. Dr Bradley Wagemaker is the medical director at Lamelle Research Laboratories. Dr Alek Nikolic is an aesthetic doctor and founder of skincare online store Skin Miles and skincare brand sk.in.Is Sunscreen Full Of Toxic Chemicals?The claim that sunscreen is toxic for human health is echoed by the Environmental Working Group (EWG), an advocacy group for environmental health. Per their research, common ingredients in sunscreen, like oxybenzone, homosalate, octisalate, octocrylene, avobenzone and octinoxate, can be absorbed by the skin at higher than safe levels, posing health concerns. Chief problematic ingredients are oxybenzone and octinoxate, which studies have linked to endocrine (hormonal) disruptions. All three experts we spoke to agreed: there is just no evidence to support this idea. Oxybenzone attracts the most concern, but experts note the lack of conclusive evidence. “These worries stem from studies conducted on cells in the lab and on animals that were fed large doses of oxybenzone. However, the amounts used in these experiments were significantly higher than what people are exposed to when applying sunscreen to their skin,” explains Dr Tarryn Jacobs, a specialist dermatologist. “It would take an individual 277 years of sunscreen use to achieve the equivalent systemic dose that produced effects in these rat studies, according to a 2017 study in the Journal of the American Academy of Dermatology,” says Dr Alek Nikolic, an aesthetic doctor.And, says Dr Jacobs, studies about chemical absorption via the skin are thin at best. “The relevance of this absorption is uncertain,” she says. “It’s critical to recognise that these two studies conducted by the FDA do not provide any evidence that chemical sunscreens cause harm. In other words, just because something is there does not mean it is causing any harm.”READ MORE: Should You Wear Sunscreen Every Day? Does Sunscreen Block Vitamin D Production?Well… this question is more of a cost-benefit quandary. For one, “The risks of sun damage and skin cancer far outweigh the minimal impact on vitamin D,” says Dr Bradley Wagemaker, medical director at Lamelle Research Laboratories. Still, it is true that sunscreen can block UVB rays, which are responsible for helping your skin produce vitamin D, explains Dr Jacobs.But! What is true in a lab simply isn’t true in real life. “Although various studies have concluded that there is a theoretical risk of sunscreen decreasing vitamin D levels, the data currently does not demonstrate a correlation in real-life settings,” explains Dr Jacobs. “In fact, several studies have shown that sunscreens are rarely applied correctly, in the right dosages and with appropriate frequency. This means that in real-world conditions, vitamin D synthesis will not be totally inhibited in sunscreen users because of the improper use of sunscreens.”The bottom line: you’re better off getting your D from food or supplements than from exposing yourself to the sun without SPF.If Skin Cancer Is On The Rise, Does That Mean Sunscreen Doesn’t Work?According to the 2023 National Cancer Registry, basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) make up the top three and four cancers in South Africa among women. Both BCC and SCC are types of skin cancer. And, from 2010 to 2017, the incidence rates for melanoma among white South Africans has increased significantly, with a 13.6% increase among women.Is sunscreen to blame for rising skin cancer rates? Experts disagree. “Studies show that regular daily use of SPF 15 sunscreen, when used as directed, can reduce your risk of developing squamous cell carcinoma (SCC) by about 40 percent and lower your melanoma risk by 50 percent,” says Dr Nikolic. He puts the rising rates down to higher UV levels, longer lifespans and improved cancer detection.Another huge contributing cancer? People. “Part of the problem is that people will sometimes use sunscreen as permission to spend excessively long periods in the sun or to tan – and on top of that, they underapply, fail to reapply and do not use other sun protection methods like hats or clothing,” explains Dr Jacobs. “This gives a false sense of security to some.” According to South African Medical Journal, among White South Africans, there is a lack of early self-screening. A South African Family Practice study reveals that only half of White survey respondents regularly use sunscreen. Among Black and Indian respondents, that number is lower. The study notes, “Less than 20% of White respondents had ever checked their skin for suspicious moles. Most Black patients were not aware that they are at risk of skin cancer, and only 10% were aware of the risk of developing skin cancers on acral sites and nails.”READ MORE: 6 Things Neurologists Would Never Do If They Wanted To Protect Their Brain HealthIs Sunscreen Only Partially Effective?As you may have guessed from the responses above, the way the average person uses sunscreen does mean its efficacy is reduced. And, according to this 2012 study, which tested the efficacy of sunscreen against deeper types of sun damage (like skin cancer), no sunscreen fully prevents deep sun damage. Authors theorised that this might be because UVA filters (in sunscreen) can break down over time and that sunscreens are not able to protect well enough against visible light. Since then, this study has spurred further research that’s substantiated the original findings. “No sunscreen can block 100% of UV rays,” says Dr Nikolic. “Additionally, the effectiveness of sunscreen can be reduced by factors such as incorrect application, inadequate reapplication, and not reapplying after exposure to sweat and/or water.”But before you ditch your SPF and bare your skin to the sun, know that “broad-spectrum SPF is still our best defence,” says Dr Wagemaker. Still, there are other ways of preventing damage. “It’s important to realise the sunscreen is just one component of a sun protection strategy, which should also include using wide-brimmed hats, wearing sun protective clothing and seeking shade where possible,” says Dr Jacobs. And apply liberally! In fact, newer formulations are innovating, with added antioxidants to mitigate sun damage where UV filters fall short. Dr Wagemaker recommends Lamelle Research Laboratories’ Helase 50+, a full-spectrum protectant from sunlight, with antioxidants to fight free radicals.How Do Sunscreens Work Against UV Light?Dr Wagemaker made this handy guide about the five wavelengths of UV light that affect our bodies:UVCThis is (technically) the most dangerous type of UV light, but thankfully, our atmosphere absorbs it, so we don’t come into contact with it on Earth. And that’s a good thing because UVC would kill you very quickly.Effects on skin: Devastating, deadly – but thankfully absorbed by the earth’s atmosphereDoes SPF work? Organic sunscreens: No. Inorganic sunscreens: No. Zinc and titanium: No. Iron oxide: Protects from 90% – 97% of this frequency.UVBThis type of UV light is most associated with pain and sunburn, and SPF is good at keeping it at bay. This frequency also creates direct DNA damage to the cells, causing what could be devastating damage. Your body does have a process of finding and correcting this damage called NER. However, sun exposure limits the capacity that the cell has to perform this process.  Effects on skin: Sunburn, DNA damage and oxidative damage to DNA and moleculesDoes SPF work? Organic sunscreens: Yes. Inorganic sunscreens: Yes. Zinc and titanium: Yes. Iron oxide: Yes (96% of this frequency).UVAThis type of UV is most associated with skin ageing because regular broad-spectrum SPF starts to fail here. From here on out, UV light tends to cause devastating DNA damage known as dimers, which the human body cannot fix on its own because of a missing protein in the human body.Effects on skin: DNA damage, mutation and cancer due to oxidative damage to DNA and molecules, as well as immune suppressionDoes SPF work? Organic sunscreen: 53%. Inorganic sunscreens, zinc and titanium: +/- 50%. Iron oxide: 85 – 95% depending on the colours used (96% – 99%).Visible lightOne of the most overlooked, and therefore most dangerous, types of UV light is the radiation in the visible spectrum. Sunscreen affords no protection against it, and it suppresses the immune system and causes free radicals to form. Our best defence against visible light is antioxidants, which are only about 54% effective.Effects on skin: Photo-ageing, mutation, and cancer due to DNA damage, oxidative damage to DNA and molecules, as well as immune suppressionDoes SPF work? Inorganic sunscreens: No, though there is some development at foot to get to the blue light spectrum. Organic sunscreens: Yes. Iron oxide: Yes, between 51% and 98%, depending on what colour combination is chosen (91 – 97%).Infrared lightAnd, of course, the invisible infrared light spectrum also affects us adversely. Infrared light from the sun causes severe oxidative stress (when free radicals ravage the DNA and body, leading to mutations) and is the most common cause of hyperpigmentation. Unfortunately, SPF 50 doesn’t help at all here. And, when SPF is combined with antioxidants, you get only 56% protection.Effects on skin: Photo-ageing, hyperpigmentation, inflammation and oxidative damage to DNA and molecules.Does SPF work? No (your best bet is antioxidant skincare)Key Takeaways From South African Dermatologists“Sunscreen is safe, effective, and essential,” reiterates Dr Wagemaker. “Misinformation can be misleading, but the science is clear: daily use of a broad-spectrum SPF is one of the best ways to protect your skin – for life.”READ MORE: Pregnancy Skin Problems! What To Expect And How To Handle It More