What are the good and the bad effects the sun has on your skin? You are probably already aware of many of the bad effects too much sun exposure can have on your skin, but before we review those, let’s start with the good effects. The first you may have already heard of – it helps boost your vitamin D production, which is important for building and maintaining healthy bones. Unlike essential vitamins that we must obtain from our diet, our body can generate vitamin D through a light driven reaction in our skin. The efficiency of vitamin D production is dependent upon the amount light that penetrates the skin and this can be influenced by clothing, sunscreen, the skin pigment melanin and even excess body fat. For a typical white person, spending 30 minutes in a bathing suit in the summer sun can generate 50,000 international units (IU) of vitamin D within 24 hours of exposure; for tanned individuals this same exposure produces 20,000–30,000 IU and 8,000–10,000 IU for dark-skinned people. To put this in perspective, the daily recommended amount of vitamin D for children up to age 12 months is 400 IU, 600 IU for people between 1 and 70 years old, and 800 IU for those 70 years of age or older. Proper levels of vitamin D can help slow down cognitive decline, reduce bone fractures and prevent osteoporosis. A vitamin D deficiency has been associated with many serious chronic diseases, including cancer, autoimmune diseases, and cardiovascular diseases. There is an estimated 30 to 50% reduction in risk for developing breast, colorectal, and prostate cancer by raising your vitamin D levels to at least 1000 IU/day vitamin D or increasing your exposure to the sun to generate similar amounts. According to the World Health Organization, getting 5 to 15 minutes of sunlight exposure 2-3 times a week on your hands, arms, and face is enough to enjoy the sun’s beneficial effects on vitamin D synthesis.
But exposure to sunlight can help our mental health too. Sunlight interacts with specific areas in our eyes that triggers the release of a hormone in your brain known as serotonin. It is linked with boosting one’s mood and helping maintain a feeling of calm and focus. With insufficient exposure to sunlight, your serotonin levels can decrease, and these are associated with an increased risk of seasonal depression. One may therefore be more susceptible to depression or during the winter months, “the winter blues”. More recently the effect of COVID on mental health has received much attention, and the effect of lockdowns and social distance measures on limiting exposure to sunlight have certainly been contributing factors.
So what about the bad effects the sun has on our skin? First and foremost, it is the effect of UVA irradiation on our bodies. We know that UVA rays from the sun can put our bodies in a state of oxidative stress or damage our DNA. It is one of the reasons why we have included vitamins E, C and bamboo extract (silica) in our product. However, with continuous depletion of the ozone layer by greenhouse gases, the amount of UVA radiation absorbed in our atmosphere is declining leading to far more rays reaching our exposed bodies. As a result, there are more new cases of skin cancer diagnosed each year in the USA compared to the combined number of new cases of breast, lung, colon, and prostate cancer. Unfortunately, one in five Americans will develop skin cancer in their lifetime and one will die from skin cancer every hour. The tragic part is that a diagnosis of skin cancer can be prevented with proper protection from harmful amounts of UV radiation.
Excessive UV radiation can also lead to actinic keratoses, a skin disorder that appear as growths or lesions, typically reddish, somewhat raised and with a rough texture often found on the hands, forearms, face, and neck. Although precancerous, they are a risk factor for a form of skin cancer known as squamous cell carcinoma.
Premature aging is another consequence of excessive exposure to the harmful UVA rays of sunlight. It occurs gradually over time, often not presenting itself until after many cumulative years of sun exposure, when the skin slowly becomes more wrinkly, thick and/or leathery in appearance. It is thus often just put off as “a normal part of getting older”. However, most of these visible skin changes that people believe are “a normal part of getting older” are caused by the sun and can be again prevented with proper protection from UV radiation.
And what about our eyes? When we are outside on a sunny day, the brightness of the sun can be very uncomfortable for our eyes and we quickly reach for our sunglasses. Typically, these have various levels of UV filtering technology, which is important as UV irradiation can increase the likelihood that you will develop cataracts. Cataracts are a type of eye damage whereby a loss of transparency in the lens of the eye leads to clouded vision. Millions of Americans suffer from cataracts and have diminished eyesight as a result. Without treatment, the cataracts can lead to blindness. Though they can be treated by surgical methods, it is at a cost of billions of dollars each year in medical care and potentially out of reach for those without medical insurance. But the good news is all of these problems can be prevented with proper eye protection, so ensure that your eyeglasses, contact lenses and sunglasses all offer comprehensive UV protection.
Take away message
So what are the good and the bad effects the sun has on your skin? For one thing it is vital for healthy vitamin D levels, and a surprising low weekly exposure is all that is required (5-15 minutes, 2-3 times per week) to ensure this. Proper levels of vitamin D promote good bone growth, maintenance of bone health and can help prevent cancer and other chronic diseases. But sunlight is also very important for our mental health, boosting our serotonin hormone levels to help put us in better mental spaces and fend off depression. But of course, like most things excessive exposure is bad, and diagnoses of various forms of skin cancer are increasing each year. It is therefore very important to protect your skin (and your eyes!) against the cumulative effect of the sun’s rays over many years. Clothing, sunscreens and UV filtered glasses are part of our defence system that are all easily available.
