Sunscreen is a crucial tool in protecting your skin from the harmful effects of the sun. It can help prevent sunburn, skin aging, and skin cancer, among other things. However, it is important to use sunscreen correctly in order to get the most benefit from it. One of the key aspects of using sunscreen correctly is knowing how often to reapply it, especially during the summer months when the sun's rays are strongest.

• The American Academy of Dermatology recommends reapplying sunscreen every two hours, regardless of the SPF (sun protection factor) of the product you are using. This is because sunscreen can wear off over time due to sweat, water, and other factors. By reapplying every two hours, you ensure that your skin is consistently protected throughout the day.

• It is important to note that the two-hour rule applies to normal, everyday activities. If you are swimming, sweating heavily, or engaging in other activities that cause the sunscreen to come off more quickly, you will need to reapply more frequently. In these cases, it is generally recommended to reapply sunscreen every 40-80 minutes, depending on the product's water resistance.

When it comes to choosing a sunscreen product, you should look for a broad-spectrum sunscreen, which means that it protects against both UVA and UVB rays. UVA rays can cause skin aging and contribute to skin cancer, while UVB rays are the primary cause of sunburn. By using a broad-spectrum sunscreen, you can protect against both types of rays.

When applying sunscreen, it is important to use enough to adequately cover all exposed skin. Most people do not use enough sunscreen, which can lead to inadequate protection. As a general rule, you should use about one ounce (or a shot glass full) of sunscreen for each application. Be sure to apply it evenly, and don't forget to apply it to your ears, neck, and any other areas that may be exposed to the sun.

Finally, it's important to remember that you should wear sunscreen daily, even if it's not summer or you're not spending a lot of time outdoors. UV rays can penetrate through clouds and windows, so you can still be exposed even if you're inside. By wearing sunscreen every day, you can protect your skin from damage and reduce your risk of developing skin cancer.

In addition to wearing sunscreen, there are other steps you can take to protect your skin from the sun. These include seeking shade during the sun's peak hours (generally between 10am and 4pm), wearing protective clothing such as hats and long sleeves, and avoiding tanning beds. By taking these steps, you can help keep your skin healthy and reduce your risk of sun damage.

In conclusion, reapplying sunscreen every two hours (more frequently if you're swimming or sweating) is an important part of using sunscreen correctly. By choosing a broad-spectrum sunscreen, using enough sunscreen to cover all exposed skin, and wearing it daily, you can protect your skin from the harmful effects of the sun and reduce your risk of developing skin cancer.