The Difference Between Physical and Chemical Sunscreens

Physical sunscreens protect your skin from the sun by deflecting or blocking the sun’s rays, while chemical sunscreens work by absorbing the sun’s rays. Some chemical filters can scatter sun rays, but still mostly just absorb them.

All sunscreens have an active ingredient (also known as a UV filter) that protects you from the sun.

Physical UV Filters:

  • Titanium dioxide (TiO2)
  • Zinc oxide (ZnO)

Chemical UV Filters:

  • Octylcrylene
  • Avobenzone
  • Octinoxate
  • Oxybenzone
  • Homosalate
  • Helioplex
  • 4-MBC
  • Mexoryl SX and XL
  • Tinosorb S and M
  • Uvinul T 150
  • Uvinul A Plus

Stability

You want to choose a sunscreen which has active ingredients that are photostable, meaning they retain their stability upon exposure to sunlight and are unchanged. Physical UV filters are generally stable, however you do want to be careful when choosing a chemical sunscreen, as not all of them stay unaffected with sun exposure (avobenzone, for instance, is notoriously unstable).

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All EltaMD sunscreens at NewDermaMed are formulated with zinc oxide, which is the most photostable sunscreen ingredient.

Comedogenicity

Many people with oilier, break out prone skin tend to stray away from using an SPF because they worry it may worsen their skin. Chemical filters tend to be more irritating to the skin, and in some cases, may even cause allergic reactions. Those with problematic skin will want to choose a sunscreen formulated with zinc oxide, as it is generally safe and can be used even on the most delicate skin. Titanium dioxide can cause problems for some people. If you break out from mineral makeup, it’s the titanium dioxide that could be the culprit.

Protection

Chemical filters generally offer more coverage against UVA and UVB rays than physical sunscreens, but the range of protection will depend on the photostability of its active ingredient. Because your skin needs to time to absorb chemicals, you need to wait 20 minutes post-application for effective sun protection.

Titanium dioxide protects against UVB rays, but not the full spectrum of UVA rays. Zinc oxide is the most photostable sunscreen ingredient, and protects against the entire spectrum of UVA and UVB rays. All physical sunscreens begin protecting you immediately upon application.

Texture

Physical sunscreens are thick and opaque, and can sometimes leave a white cast or tint on the skin. It can rub off more easily and must be frequently reapplied. Chemical sunscreens are colorless, odorless, and usually runny. They can even double as a makeup primer, depending on the active formulation.

Safety

All physical sunscreens have been deemed safe and are completely approved by the FDA. While chemical sunscreen are generally safe, some chemical filters can actually generate free radicals, which can cause skin damage, irritation, and even aging. Many chemical UV filters have not been approved by the FDA, but are commonly found in sunscreens sold in Europe and Asia.

Photoaging and UV Exposure

As part of the Ontario Skin Cancer Prevention Act, youths under the age of 18 have been banned from using tanning beds as of this past Thursday, May 1st – perfectly timed, considering May is Skin Cancer Awareness Month. The goal of the legislation is to protect young people, who are especially vulnerable to damage from UV radiation leading to skin cancer. According to the World Health Organization, the use of tanning beds by individuals under the age of 35 increases your chance of skin cancer by a whopping 75%. In fact, the WHO classifies tanning beds among its highest risk category, which includes tobacco and asbestos.

Aside from serious health effects, long term exposure to UV rays has been proven to cause photoaging by damaging the skin’s collagen and elastin fibres, resulting in premature wrinkles and fine lines. Other side effects of prolonged UV exposure are as follows:

  • Both UVA and UVB cause damage to DNA, with UVB in the epidermis and UVA deeper in the dermis.
  • This damage causes mutations in the p53 tumor suppressor gene, a gene responsible for repairing damaged DNA (if possible), or discarding cells that are damaged beyond repair.
  • If p53 doesn’t function properly, these highly damaged cells continue to multiply.
  • Around 50% of skin tumors have this mutated p53 gene in them.
  • UVA penetrates deeper into the skin reaching the dermis where collagen, the structural scaffolding of the skin, is located. This causes the skin to sag in places leading to wrinkles.
  • Both UVA and UVB cause the number of Langerhans cells, an important part of the immune system, to decrease, lowering immunity.
  • UVA increases the number of inflammatory cells in the dermis.

Generally, the effects of UV exposure on the skin are permanent, however, thanks to scientific breakthroughs and advances in medical grade technology, they can be minimized and in some cases, completely reversed. Professional treatments like IPL Photo Rejuvenation and Laser Genesis are specifically designed to treat the most common age concerns that are so often a direct result of excessive tanning in our youth, such as deep wrinkles, fine lines, loss of skin elasticity, uneven tone and texture, redness/Rosacea, freckles and age spots, etc;

Taking simple precautions in your everyday routine, such as wearing sunscreen, can also have a hugely positive effect on the overall/longterm condition of your skin. Always choose an SPF formulated with zinc oxide, which is far more photostable than any other sun protecting ingredient.

Spring Towards Healthy Skin!

With the season changing, so should your skin care regimen. As we head into the warmer weather, your skin care routine needs to be adjusted in order to keep your skin healthy and beautiful.

Lighten Up

The heavy moisturizing cream that you used in the wintertime may be a little too heavy during spring and summer months. Instead, switch to a sheer, lightweight moisturizing sunscreen, such as EltaMD’s UV Daily SPF 40. Formulated with Hyaluronic Acid, it increases skin’s smoothness and significantly decreases wrinkles over time, while the 9% transparent zinc oxide offers some serious broad-spectrum UV protection without the pasty white, chalky residue – it’s so light, it’s almost invisible! For those of you on the more sensitive side, this moisturizer is also fragrance-free, paraben-free, and noncomedogenic.

Makeup palettes should lighten up as well. Set aside your dark lipsticks and shadows and opt lighter neutrals and soft pinks. For daytime use a lip gloss rather than a lipstick, and replace your heavy liquid foundation with a mineral powder or tinted sunscreen (EltaMD’s Tinted UV Physical SPF 41).

Scrub Down

Sloughing off dead skin is a must in any skin care routine, regardless of the season. Regular exfoliation helps you get a closer shave, prevents in-growns, and allows your serums and moisturizers to penetrate deeper. Stay away from products with large, jagged granules, which are quite harsh on facial skin and cause little microscopic scratches on the epidermis, which can lead to a multitude of issues such as broken capillaries, scarring, and hyperpigmentation.

Professional microdermabrasion devices use fine crystals, which pass over the skin with a vacuum or air pulsating wand. This process gently “sandblasts” dead skin cells and rough patches left behind from the dry, winter air, leaving you with a noticeably refreshed complexion immediately after your treatment.

Chemical peels are ideal for eliminating surface-level blemishes and imperfections. A peeling agent (aHA or bHA) is applied to the skin and as a result, the uppermost layer of dead skin slowly peels off. In just a matter of days, dull, rough skin is replaced by a smoother, more radiant complexion. There are a number of at home products that can be used to maintain the results of your chemical peel in between sessions that contain aHAs or bHAs, depending on your skin’s needs. Drier skins, for example, may want to opt for products containing lactic acid (a hydrating aHA derived from milk), like the PCA Nutrient Toner, while those prone to break outs should look for ingredients like salicylic acid (a bHA derived from willow bark that works against P. acne bacterias) such as Circadia’s Cleansing Gel with Salicylic Acid.

Rehydrate From the Inside Out

Those of us with dry skin know all too well how miserable of a feeling it is to have skin that feels less like a baby’s bottom and more like a sheet of sandpaper. Dry/dehydrated skin can cause all sorts of discomfort, such as peeling, flaking, cracking, redness and itching. The good news is you can avoid that all-over itchy feeling by taking time to keep your body well hydrated from the inside out.

The obvious solution to dry skin is to slather on a good moisturizer or hydrating cream, but we often forget that what we put into our bodies is just as important (if not more) as what we put on. By consuming at least 8 to 10 glasses of water a day (or more, for people who are highly active and sweat a lot), not only are you flushing out toxins and other impurities from your body, but you are also maintaining your skin’s hydration levels and elasticity — remember: dry skin ages a lot faster!

If you’re looking for an instant fix, oxygen facials are the way to go. Popular amongst A-list celebrities (some self-confessed fans include Jennifer Lopez and Gwyneth Paltrow), oxygen facials use fine mists of oxygen infused with medical grade hyperbaric oxygen and vitamin serums to instantly plump, hydrate, and smooth skin. The germicidal action also makes it extremely beneficial for acne sufferers, and the lightening and vaso-constricting capabilities give instant results for rosacea. The procedure is a quick 30 minute procedure that is beneficial for all skin types and can be repeated as often as once a week.

Spring Clean Your Makeup Bag

When was the last time you looked at your makeup bag (and I mean really looked at it)? Some important factors to consider while debating whether or not it’s time to toss and replace a beauty product are the type of makeup, how it’s been stored, and whether or not you’ve had any cold sores, skin rashes or eye infections. Some cosmetics shouldn’t be kept longer than 3 months, while others (such as nail polishes) can be stored for a couple of years. The following is a general guideline for how long your makeup should be kept:

  • Mascara: Three months
  • Lipstick: One year (some people say longer, so do what’s comfortable)
  • Powder: Up to two years (but wash your applicator regularly)
  • Foundation: 12 to 18 months (oil-based products last longer)
  • Eye and lip pencils: Up to three years (sharpen regularly)
  • Brushes: Wash every 2 to 3 weeks
  • Sponges: Wash weekly, discard monthly

Shave Smart

Let’s be honest here — how many of us actually took the time to shave our legs in the winter as often as we do in the summer? After all, if you’re covered up all day or snowed in from a polar vortex, why bother?

Before you grab the razor, take a few extra minutes to exfoliate your entire body to remove any dead skin from your neck all the way down to your toes. Once you’ve finished shaving, apply your moisturizer while your skin is still a little damp, which helps to lock in moisture and greatly reduces your chance of getting razor bumps.

For those of you who are tired of shaving everyday to avoid that cactus-like feel, laser hair removal is a permanent solution for unwanted hair. Modern, high tech laser treatments can painlessly reduce hair growth on any area of the face or body is as little as 4 to 6 sessions. Designed to be the most outstanding laser hair removal system of modern cosmetic laser technology, the Cutera CoolGlide Nd:YAG at NewDermaMed is the only laser technology that is safe and effective for all skin types. Staying true to its name, the CoolGlide handpiece cools and soothes as it glides along your skin, greatly reducing any feelings of discomfort during the treatment.

NEW PRODUCT: EltaMD UV Clear SPF 46

We’re very excited about this new product! Leading sunscreen maker EltaMD has released a hydrating sunscreen specially formulated for acne prone skin. With an SPF of 46, this oil-free, noncomedogenic moisturizer leaves no residue, while calming and protecting sensitive skin types prone to acne, rosacea and discolouration from harmful UVA/UVB rays. This silky, lightweight formula can be worn alone or under makeup.

All EltaMD sunscreens are formulated with a natural mineral compound called zinc oxide. Unlike some chemical ingredients that may degrade, zinc maintains its protective ability in the sun, making it far more photostable than any sun protecting ingredient. Zinc blocks the widest spectrum of UVA and UVB rays while keeping the skin from burning and minimizing the premature appearance of aging and risk of skin cancer. Zinc is safe for even the most sensitive skin types!

Image via EltaMD.com

Remember: The risks associated with sun exposure are not exclusive to the summer season, and protection from UV radiation is important all year round. UV rays from the sun can reach you even on cloudy days, and also reflect off of surfaces like water, cement, sand, and snow.