Skin aging and Sunscreen.

Understanding and Protecting Against Skin Aging.

Skin aging is a natural process, but not all signs of aging are created equal — or inevitable. To fully understand how to care for your skin and prevent long-term damage, it's important to recognize the different types of aging. Each has its own causes, effects, and ways to manage or prevent them — and sunscreen plays a vital role in all three.

Chronological aging is the natural aging process driven by genetics and the passage of time. As we get older, our skin gradually becomes thinner, drier, and less elastic. This type of aging is not preventable, but its effects can be minimized through consistent skincare, a healthy lifestyle, and targeted treatments like retinoids, peptides, and hydration-boosting ingredients.

Photoaging, on the other hand, is caused by long-term exposure to UV radiation from the sun and tanning beds. It’s the leading cause of visible aging — including wrinkles, discoloration, and rough texture — and is completely preventable. Severe photoaging - such as deep wrinkles, leathery texture, sagging from collagen breakdown, and extensive pigment changes --cannot be fully reversed. Over time, repeated UV damage causes permanent structural damage in the skin, including damage to DNA, collagen and elastin fibers. So there is a point where photoaging becomes irreversible, this is why early prevention and treatments such as chemical peels, laser resurfacing, and antioxidant-rich skincare and constant protection (especially with sunscreen) is critical.

Premature aging occurs when external factors — like UV exposure, pollution, smoking, or poor skincare habits — accelerate the skin’s aging process. This means signs of aging appear earlier than expected. Like photoaging, it’s largely preventable. Lifestyle changes, consistent sun protection, and antioxidant support can slow down this process and keep skin looking younger, longer. 80% of premature aging is caused by UVA rays.

By understanding the differences between these types of aging and how they overlap, you can take proactive steps to protect and care for your skin. And what is at the center of it all?

What are UVA and UVB Rays?

UVA and UVB rays are types of ultraviolet radiation from the sun that affect the skin differently. UVA rays, known as "aging" rays, penetrate 40% deeper into the skin than UVB, causing aging, loss of firmness, wrinkles, and hyperpigmentation. These rays can pass through glass, meaning you are exposed to them even when indoors, such as in a car, house, or office. 80% of premature aging is caused from UVA rays and is there rain or shine.

UVB rays, referred to as "burning" rays, are responsible for causing sunburn. Both UVA and UVB rays contribute to the development of skin cancers.

Sunscreen — the most powerful anti-aging product you can use every single day.

The main purpose of wearing sunscreen is to protect your skin from the harmful effects of ultraviolet (UV) radiation from the sun. This protection also helps prevent sun allergies, heat exhaustion, sunburn, premature aging, photoaging, skin cancer. It maintain the skin's natural barrier and overall health.

What is SPF (Sun Protection Factor)?

In sunscreen, SPF measures how effectively the product blocks UVB (burning) rays. An SPF of 30 means it would take approximately 30 times longer for your skin to burn compared to not wearing any sunscreen. SPF 30 blocks about 97% of UVB rays, while SPF 50 blocks around 98%. Higher SPFs offer only slightly more protection but may lead to overconfidence in the product being applied.

Selecting the best sunscreen

The Skin Cancer foundation recommends a broad spectrum sunscreen with an SPF 30 or higher.  Skin type and family history are factors in determining the level of protection you need. Certain medications and disorders make skin highly sensitive to the sun, raising protection requirements. 

Chemical or physical sunscreens?

The key difference between chemical and physical sunscreens lies in how they block rays. Physical (mineral) sunscreens sit on the surface of your skin and act as a shield, while chemical sunscreens sink into your skin and act more like a sponge. Here’s more to know.

1. Mineral (Physical):

   • Active Ingredients: Zinc oxide, titanium dioxide

   • Sits on top of the skin and reflects UV rays from your skin.

   • Great for sensitive skin, children, and those with acne. 

   • Starts working immediately.

   • Can leave a white cast (though newer formulas minimize this).

2. Chemical:

   • Active Ingredients: Avobenzone, octinoxate, oxybenzone, octocrylene, etc.

   • Absorbs UV rays so your skin does not. 

   • Needs to be applied about 15–30 min before sun exposure.

   • Can be irritating for sensitive skin or post-procedure.

Choose a sunscreen you'll use and reapply frequently, even on cloudy days.

Up to 80% of the sun's UV radiation reaches the earth, so apply it daily.

There has been debate about sunscreen ingredient safety, but the FDA hasn't found evidence of harmful side effects for most chemicals. However, they have banned aminobenzoic acid (PABA) and trolamine salicylate. The FDA continues to evaluate the safety of active ingredients beyond zinc oxide and titanium dioxide.

Check the expiration Dates.

Most sunscreen bottles will have an expiration date printed on the packaging, indicating when the product is no longer guaranteed to provide its stated level of protection. 

• FDA Requirements:  The FDA requires sunscreens to remain effective for at least three years from the manufacturing date. 

• Why Expiration Matters:  Over time, the active ingredients in sunscreen will degrade, reducing the effectiveness of the product. 

• Storage:  Proper storage can help prolong the life of sunscreen. Avoid storing it in direct sunlight or extreme heat, as this can accelerate the degradation of its active ingredients. 

Why reapply?

Even if you applied it perfectly in the morning, sunscreen doesn’t stay effective all day. Reapply every 90 minutes. Here's why.

• It Breaks down in the sun.  Sunlight literally breaks down sunscreen ingredients over time. After a couple of hours, they just don't protect as well.

• You lose it through normal activities.  Sweating, touching your face, or rubbing with a towel removes sunscreen.  Even just natural oil production and facial movement can wear it off.  Swimming or sweating heavily? You’ll need to reapply even sooner.

• Most people don’t use enough.   Even if the label says SPF 50, if you didn’t apply enough, it’s more like SPF 10 or 15 in practice. Reapplying gives you a better chance at maintaining solid protection throughout the day.

How much sunscreen should I use?

Adults should use one ounce -about a shot glass- for the whole body. Children should use about half that amount. For the face alone, a nickel size amount. When in doubt, use more than you might think.

It’s important to remember that no sunscreen filters out all UV rays. Hats, protective clothing, and sunglasses are also good ways to help limit additional sun exposure. 

Do moisturizers with SPF replace Sunscreen? 

Sunscreen is not an ingredient; it should be treated as a very important layer in your skincare routine and should always be applied last (but before makeup). 

The purpose of sunscreen is to form a protective film on top of the skin to shield it not to restore moisture balance or deliver ingredients deeper into the skin.

Sunscreen is regulated by the FDA as a drug and those regulations require a specific amount of SPF in order for it to be effective, leaving little room for other active ingredients in a formula. The amount you put on your face may not be enough, it will be diluted by the moisturizer. 

Use a dedicated sunscreen as your last skincare step every morning, especially if you're going outside—even if your moisturizer has SPF.  If you love your SPF moisturizer, you can use it under a lightweight broad-spectrum sunscreen, or apply more generously than you would a normal moisturizer to get better protection.

A base tan does not protect you against the sun!

By definition, a suntan is your skin’s defense to being harmed by UV exposure.  Your cells response is producing more melanin(pigment), and your skin darkens as a result.  There is nothing healthy or preventive to be gained from trying to acquire a base tan.  According to the US surgeon general, a “base tan” provides a sun protection factor of 3 or less. 

Does Sunscreen Protect Against HEV (Blue) Light?

High-energy visible (HEV) light is short-wave light in the violet/blue band of the visible spectrum.  It can penetrate deep into the skin and eyes, potentially causing photoaging and contributing to retinal damage.  

• Mineral sunscreens and tinted sunscreens containing Zinc Oxide (especially those with iron oxides) can block some HEV (blue) light.

• Traditional chemical sunscreens (like ones with avobenzone, octinoxate, etc.) mainly protect against UVA/UVB — they do not protect well against visible blue light.

• Some newer sunscreen formulas are specifically made to protect against HEV light and will say "blue light protection" or "digital defense" on the label.

• Antioxidants (like Vitamin C, Niacinamide) don't block light but help neutralize free radicals caused by blue light damage.

• Everyday use matters even indoors if you spend lots of time on phones, laptops, or under fluorescent/LED lighting.

Knowing the different types of skin aging — and how sunscreen, targeted skincare treatments and products fits in — can make a big difference in keeping your skin looking healthy and youthful. When you understand what causes aging (like time, sun, and lifestyle habits), it’s easier to take steps that actually work. Wearing sunscreen every day is one of the simplest and most powerful ways to slow down the signs of aging and protect your skin for the long run.