Do I Still Need To Wear SPF In Winter?
Wearing SPF in winter is just as important as wearing SPF in summer. Harmful UV rays are still able to cause damage to your skin, which causes long-term damage if you sustain repeated exposure.
SPF stands for Sun Protection Factor and it measures how well a sunscreen protects your skin from ultraviolet B (UVB). The higher the SPF number, the more protection your skin receives from UVB. Choosing the correct level of SPF is important to prevent sunburn, skin damage and potentially skin cancers.
The number an SPF claims to be tells you exactly what percentage of harmful sun rays are blocked when applied correctly. For instance, SPF 30 blocks about 97% of UVB rays. A higher SPF offers you more sun protection, however it is important to note that no level of SPF blocks 100% of UVB rays.
Sunscreens can use two types of active ingredients which protect you from the harmful sun rays. The first is a physical filter which uses tiny mineral particles, such as zinc oxide. These minerals sit on top of the skin and reflect or scatter UVB rays, acting like a shield. The second type of active ingredient sunscreen may use is a chemical filter. These use carbon-based compounds, like avobenzone, to absorb incoming UVB rays and convert them into heat which is then safely released from the skin.
In winter, you should still be wearing SPF when the UV index sits above a 3, or you are spending extended periods of time outside. Whilst UVB rays may be blocked by clouds or glass, UVA rays remain consistent year round. They are able to penetrate through winter clouds and the thinner winter ozone layer. Fresh snow is also able to reflect 80-90% of the sun's UV rays which means you are still susceptible to skin damage throughout the winter months. By applying SPF throughout winter, you are protecting your skin from cumulative damage, meaning you are less susceptible to long-term damage.
By choosing not to wear sunscreen, you are exposing your skin to a range of short-term and long-term skin damage. Immediately after 15 minutes of UVB exposure, your skin is susceptible to sunburn, where the harmful rays damage the outer layer of your skin, causing redness, pain and swelling. Following this, the skin enters a state of acute stress and inflammation which can worsen acne and slow down the healing process.
The long-term effects of UVB and UVA exposure includes premature aging, hyperpigmentation, skin damage accumulation and in extreme cases, skin cancer. Repeated sun exposure alters and mutates cellular DNA which significantly increases your risk of developing serious skin cancers, such as melanoma.
To ensure you are receiving all the benefits of your SPF, you need to ensure you are applying it correctly. Firstly, you need to be using broad-spectrum SPF with an SPF of 30 or higher, which is a type of sunscreen which blocks both UVA and UVB rays.This ensures that you are protecting your skin from as many short & long-term effects as possible. The American Academy of Dermatology recommends using around a shot glass worth of sunscreen (around an ounce) to cover your entire body and teo finger lengths for your face and neck. To ensure your skin has absorbed the sunscreen, you should apply the SPF 15 minutes before sun exposure, followed by reapplying every 2 hours or after swimming, sweating or towel drying.
