How to choose a sunscreen
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Sunscreen is an essential part of your skincare routine - it helps to protect your skin from the harmful effects of the sun's ultraviolet (UV) radiation such as skin cancer, aging and pigmentation. However, with so many products on the market, it can be overwhelming. In this article, we will discuss the crucial factors to consider when selecting the perfect sunscreen to keep your skin healthy and beautiful.

Sun Protection Factor (SPF)

The first thing to look for in a sunscreen is its Sun Protection Factor (SPF), which indicates how effectively it well it can protect your skin from ultraviolet light which is responsible for causing sunburn and contributing to skin cancer. Dermatologists recommend using a sunscreen with an SPF of at least 30, which means that, if applied in the recommended quantity, the amount of ultraviolet light reaching your skin is reduced 30 times. For extended outdoor activities, opt for a higher SPF for increased protection. In reality most people do not apply as much sunscreen as is advised - approximately an egg cup full is recommended for the face alone and therefore the amount of protection that you will get is less than the SPF.

Broad and Extended Spectrum Protection

The ultraviolet light spectrum is divided into UVB rays which penetrate more superficially and are responsible for causing sunburn and UVA rays can which penetrate more deeply causing premature aging and increasing the risk of skin cancer. A broad-spectrum sunscreen offers protection against both UVA and UVB rays. The large majority of modern sunscreens will have broad spectrum protection.

Blue light, a component of visible light with a wavelength ranging between 400 and 495 nanometers, is emitted by various sources and in recent years, research has shown that exposure to blue light from the sun might contribute to hyperpigmentation through activation of a opsin 3 - a photoreceptor present in human skin cells - leading to increased melanin production. The evidence surrounding blue light produced from screens is less convincing. Look for extended spectrum photoprotection if you wish to protect yourself from blue light in addition to ultraviolet light.

Water Resistance

If you plan on swimming or engaging in exercise that will cause sweating, a water-resistant sunscreen is essential. Water-resistant sunscreens better maintain their protective properties while immersed in water or sweating but still need to be re-applied.

Skin Type and Sensitivity

Your skin type and sensitivity can also play a significant role in your sunscreen choice. If you have oily or acne-prone skin, opt for oil-free or non-comedogenic sunscreens that won't clog pores. For sensitive skin, choose a product free of fragrances, parabens, and other potential irritants. Individuals with dry skin may benefit from sunscreens containing moisturizing ingredients like glycerin or hyaluronic acid.


Sunscreen is available in various forms, such as creams, lotions, gels, sprays, and sticks. Creams and lotions are ideal for most skin types, while gels work well for oily or hairy areas. Sprays can be convenient for hard-to-reach spots and quick application, but ensure you apply a sufficient amount and rub it in for even coverage. Sticks can be suitable for the face, particularly around the eyes, as they are less likely to run and cause irritation.

The protective factor in Sunscreens can be either chemical or mineral.

Chemical sunscreens contain organic compounds that absorb UV radiation. These sunscreens are popular due to their lightweight texture and easy absorption. They typically leave no white residue, making them suitable for all skin tones. However they can cause skin irritation or allergic reactions in sensitive individuals. Some chemical ingredients, such as oxybenzone and octinoxate, have been linked to coral reef damage and harm to marine life.

Mineral sunscreens, also known as physical sunscreens, contain inorganic compounds like zinc oxide or titanium dioxide, which act as a physical barrier on the skin's surface, reflecting and scattering UV radiation. They also provide extended spectrum photoprotection including blue light. They are less likely to cause irritation or allergic reactions, however can have a heavier texture and leave a white cast on the skin, particularly on darker skin types.

How to apply

A general rule of thumb is to use approximately a shot glass full of sunscreen to cover your entire body. For the face and neck, an egg cup full is advised. It is essential to apply a generous and even layer of sunscreen to all exposed skin as under-applying sunscreen can result in considerably reduced protection.

Sunscreen should be reapplied every two hours when outdoors, as its protective properties are diminished by ultraviolet light exposure. Reapplication is particularly crucial on hot and sunny days, as sweating can cause sunscreen to wear off more quickly.

If you're swimming or engaging in activities that cause excessive sweating, use a water-resistant sunscreen and reapply it immediately after you get out of the water or towel dry.

Don't forget to apply sunscreen even on cloudy or overcast days, as the sun's UV rays can penetrate through clouds causing damage.

Lips and other overlooked areas: It's easy to forget some areas when applying sunscreen, such as the lips, ears, and the tops of your feet. Use a lip balm with SPF and ensure that you cover all exposed areas for comprehensive protection.

Applying the right amount of sunscreen and reapplying it at regular intervals is essential for keeping your skin safe from the sun's harmful rays. Make sure to use approximately one ounce of sunscreen for your body, apply it at least 15-30 minutes before sun exposure, and reapply every two hours, or after swimming or sweating. By following these guidelines, you can maintain effective sun protection and help prevent skin damage, premature aging, and skin cancer.


Selecting the right sunscreen is crucial for protecting your skin from the sun's harmful rays. By considering factors such as SPF, broad-spectrum protection, water resistance, skin type, formulation, and environmental impact you can choose a sunscreen that meets your specific needs.

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