Tag Archives: UV radiation

Skin Cancer and Aging: Causes and Solutions

By Hui Xie-Zukauskas

UV radition n Ozone layerHere comes the sun! And we all enjoy it. You may be heading for sunny beaches soon. I’d like to remind you of damage from the sun overexposure. By providing some key insights into harmful effects of the sun, and reflecting on skin aging, I am diving a little deeper into this subject, and will equip you with a sun protection tool kit – 5 Essentials or “SHADE”.

Numbers and Notions

First, do you know that more people suffered from skin cancer than all other cancers combined over the past three decades? Breaking down the statistics, it reveals approximately 40-50% of Americans who live to age 60+ will have one type of common skin cancers, and more than 90% of skin cancer is caused by excessive or unnecessary exposure to the sun?

Types of skin aging

If the above numbers cannot transmit the roles of aging and sun hazard in skin cancer, let me briefly elaborate what happened to our skin over our lifetime. As we age, our skin – the largest organ in the human body – goes through the same escalating loss of structure and function as other organs. But unlike other organs, the skin is openly exposed to environmental pollutants and lifestyle-related hazards (e.g. excessive sun, tanning, smoking, etc.). ALL is cumulative! Mostly concerning, ultraviolet (UV) radiation from sunlight causes so called “photoaging”.

I summarize here how photoaging differs from natural skin aging, to help you understand how biological evolution of the skin and adverse effects of the sun are interplayed.

Natural / Intrinsic Aging Photo- / Extrinsic Aging
Cumulative process Yes Yes
Common locations face, neck, forearm, and lower leg Yes
Cause Aging-related Sun damage overlaying natural aging
Visible characteristics Looseness, sagginess, fine wrinkles, dryness Increased pigmentation, deep wrinkles, harsh or rough skin
Structural alterations Epidermal − dermal area thinning and weakening, reduced elasticity, delay in wound healing Severe damage of dermal and connective tissues, promoting age-related skin diseases and skin cancer

Fundamental nature of Sun Damage

UV radiation is a known human carcinogen (i.e. cancer-causing agent). Let me expand further on UV radiation as a major causal factor of skin cancer and premature skin aging at cellular and molecular levels.

  1. UV radiation can modify DNA, intensify oxidative stress, and alter cellular antioxidant and immune defense, as well as other cellular structural or signal transduction pathways.
  2. UV-induced immune suppression contributes considerably to skin malignancies.
  3. UVB can directly cause specific DNA damage, when left unrepaired, it leads to mutations, consequently predisposing individuals to any cancer.

Importantly, bear in mind that UV exposure in children under age 10 has been linked to an increased risk of developing melanoma (malignant) and non-melanoma skin cancer later in life. Thus, childhood is a susceptible window for long-term dangerous effects of sun damage.

Sun safety with 5 Essentials – SHADE

Fortunately, skin cancer is one of the most preventable types of cancer. So, how can you protect yourself and your family? Employ this tool kit, i.e. the acronym “SHADE”.

S stands for “Sunscreen application”

A wide variety of sunscreens are available on the market but not all products are created equal. Make sure to use sunscreens that block both UVA and UVB. In addition, use a moisturizer with SPF 15 or higher on a daily basis.

H stands for “Hide away from the sun”.

Whether you stroll under the sun or enjoy outdoor adventures, wear sunglasses, a hat, and cover up with loose clothing. Also, make sure your sunglasses have both UVA and UVB blocking properties. 

A stands for “Avoid the sun during its most intensive time”

Staying away from the sun is especially paramount between the hours of 11 a.m. and 3 p.m., because during this window of time, the sun is at its strongest, thereby making this time the riskiest for sun damage.

D stands for “Detect early and Defense daily”.

Skin cancer can occur just about anywhere on the skin, but most often on the areas exposed to the sun, of course, also in odd places. With that in mind, look out vigilantly for moles, bumps or spots, by following the “ABCDE” guidance from WebMD, and noticing pain or fluid as a red flag too, for early detection. Schedule an annual skin cancer screening if you are among those “high risk” individuals.

In addition, antioxidants are powerful weapons to fight or “catch” free radicals generated from UV. Hence, build up your antioxidant defense by eating plenty of fresh, colorful fruits and vegetables, and more salmon.

E stands for “Educate everyone”.

To emphasize, E is for educating, not entertaining under the sun! Start with children and young adults. Regardless of gender and age, we are all exposed to the same sun. Today, the sun is getting less merciful compared to three or more decades ago due to thinning of ozone protection.

Take home message: 

Keep a balance between sun pleasure and sun damage, and hold the value of proper skin care. At the end, healthy skin in the course of life may promote better mental and emotional health. And remember “SHADE”.


Reference (on the table): Quan & Fisher. Gerontology. 2015; 61:427-34.

Image credit: thezonehole.com

7 Natural Nutrients and Powerful Antioxidants for UV Protection

By Hui Xie-Zukauskas

Fruits-Veggies_4566Have you ever gone for grocery shopping, wondering how to take advantage of natural foods for your UV protection? Or you might be just thinking loud “Help me – Help me with a shopping list for natural resources of antioxidants that fight UV and Sun damage!

Hey, this is a health-smart idea or initiative. After all, UV radiation causes DNA damage leading to skin aging and skin cancers. Although the skin holds many protective mechanisms against UV damage, the combination of accumulated exposure and UV-induced immunosuppression can overwhelm the skin’s natural defense. There are a myriad of natural resources for your protection.

To combat UV’s harmful effects and strengthen your skin defense, I’m going to put seven types of super foods and nutrients on the spotlight in this post, and talk about how they provide UV protection.

1.      Carotenoids

Carotenoids micronutrients can scavenge free radicals that cause DNA damage to skin, and protect skin injury and/or problems resulting from sun damage and UV radiation. In general, colorful veggies and fruits with bright natural pigments are signals of carotenoids-rich foods, such as carrots, red, yellow or orange peppers, and oranges.

2.      Lycopene

Tomatoes are lycopene-rich super food; and lycopene can neutralize the harmful effects of UV light by scavenging skin-damaging free radicals. Additionally, tomatoes also contain beta-carotene and vitamin C. In the summer, as well as in all seasons, it is so easy and refreshing to include tomatoes in virtually any dishes from salad to pizza and side dish. Grape/Cherry tomatoes can be excellent snacks!

3.      Resveratrol

Resveratrol has antioxidant, anti-inflammatory, anti-aging, and anti-viral properties. It also exerts cardioprotective, neuroprotective and analgestic actions. Research shows that resveratrol can regulate cellular activities in response to radiation and thus minimize UV radiation-initiated damage. Furthermore, resveratrol can neutralize free radicals generated from UV rays and counteract their harmful effects. Grapes are an superb source of resveratrol. Other foods containing resveratrol include wine, grape juice, cranberries, cranberry juice, and peanuts.

4.      Flavonoids

Dark chocolate is a wonderful source of flavonoids, which is well known for the protective benefits of the heart and blood vessels. Interestingly, research also suggests that dark chocolate protects the skin from sun damage. So, give yourself a treat or an excuse to consume it regularly, but not excessively. In addition, flavonoids-rich natural cocoa butter helps preserve skin’s elasticity and moisture.

5.      Green tea

Green tea is loaded with polyphenol antioxidants, which have protective effect on UV-induced skin inflammation, oxidative stress and DNA damage. Green tea is also rich in catechins, which are known to have extremely powerful antioxidant properties. A cup of iced green tea in hot summer days serves as not only a beverage to ensure adequate hydration and promote youthful skin, but also a guard to prevent UV-induced DNA damage and reduce skin cancer risk. Green tea can be a great substitute for Coke or other sugar-packed soft drinks.

6.      Salmon

We all know that salmon provides an excellent source of omega-3 fatty acids. However, do you know that salmon helps build your skin defense? Research shows that Omega-3 essential fatty acids may protect skin damage and premature aging from UV radiation, this is because salmon also contains astaxanthin, a powerful antioxidant that can scavenge free radicals produced from the skin after sun or UV exposure. Additionally, astaxanthin helps alleviate the pain and inflammation associated with sunburn.

7.      Greens

Go greens! And you’ll never go wrong. Green leafy veggies are delicious, nutritious, and they help protect your skin damage from sun and UV radiation. Greens are the great sources of beta-carotene, lutein and zeaxanthin, vitamin C and E – a full spectrum of carotenoids micronutrients and vitamins.

Certainly, dietary intake of antioxidants in terms of UV protection is considerably slower than topical application achieved by using sunscreens. However, an optimal supply of natural antioxidant micronutrients in the skin can enhance skin antioxidant defense against UV radiation damage, support your long-term wellbeing, and maintain your skin health and glowing appearance.

I hope that today’s grocery checklist is valuable for your UV protection and particularly beneficial for people at the greatest risk of skin cancer and other cancers as well.


Image credit: by Fruits-Veggies_4566

What You Need to Know about UV Radiation

By Hui Xie-Zukauskas

UV radition n Ozone layerHere comes the sun! And we all enjoy it. Humans live with many benefits from the sun, as do organisms including plants, animals, and microorganisms. But today, let’s face an unfavorable side of the sun by examining some harmful effects of ultraviolet (UV) radiation from the sun, in association with skin cancer.

The sun, of course, is a major source of UV rays, and our skin is a natural target of UV radiation. Excessive exposure to UV radiation is the most significant risk factor for skin cancer. Skin cancer is the most common type of cancer in fair-skinned populations in many parts of the world, including the United States. An alarming reality is that the incidence and rates of morbidity and mortality of skin cancers are increasing! Over 2 million of Americans are diagnosed with skin cancers annually, and an estimated 9,710 people will die of malignant melanoma in 2014.

So, what do you need to know in order to have a clearer understanding of UV radiation damage?

Important facts

Fact 1: The main clinical manifestation of UV exposure can be classified into

  •  Immediate effects, including sunburn, tanning, vitamin D production, and various skin disorders as well as deterioration of these ailments.
  •  Long-term effects, including skin aging and skin cancer.

Fact 2: UV exposure in children under 10 years old has been linked with an increased risk of developing melanoma and non-melanoma skin cancers later in life.

Fact 3: High numbers of nevus (or mole), freckles, red hair, blue eyes, and inability to tan, as well as a family history of skin cancer are the primary determinants of melanoma among adolescents.

Key factors

  1. The amount of UV radiation reaching the earth’s surface depends on ozone depletion, increased UV light, latitude, altitude and weather conditions.
  2. The amount of solar UV received by children and teenagers makes up 40-50% of total UV for individuals living to age 60.
  3. Unnecessary exposure to the sun and artificial UV radiation (e.g. tanning lamps) creates a significant personal attributable risks.
  4. Hereditary or familial melanoma accounts for approximately a tenth of all melanoma cases.

Vital damages

UV radiation is a known carcinogen. The effects of UV radiation are primarily mediated via direct damage to DNA in the skin cells and immune suppression of surveillance mechanisms.

  1. DNA damage includes single strand breaks, inter-strand cross-links, and nucleotide base modification as well as mutation. All wavelengths of UV radiation cause DNA damage to skin cells.
  2. UV-induced immune suppression contributes considerably to the growth of skin malignancies – both melanoma and nonmelanoma skin cancer. One of the immune defenses is an important surveillance system that maintains genomic integrity through cell cycle checkpoints. Once these checkpoint mechanisms sense the abnormal DNA structures, they execute cell cycle arrest and coordinate it with the DNA repair process. Imagine what the consequence would be when UV radiation inhibits immune surveillance.

Finally – Preventative strategies

  1. Keep a healthy practice of reasonable sun avoidance.
  2. Use sunscreens, and use in all the seasons if necessary.
  3. Consume antioxidants. Oxidation by free radicals mediates DNA damage upon UV insult, so antioxidants with direct free radical scavenging properties are considered as promising radiation modifiers or protectors.

Again, it is important to remember: childhood is a susceptible window for long-term harmful effects of UV radiation.

Image credit: by www.theozonehole.com

Protect Your Skin to Prevent Cancer

By Hui Xie-Zukauskas

Colour-blast-sun 1031204-mYou’ve probably heard a lot about sun protection and skin cancer prevention. But since you may be heading for sunny beaches or the swimming pool soon to enjoy sun bathing or to get a tan, you may want to learn a bit more about how sun protection can be critical for your health and your skin. So today, I’ll dive a little deeper into this serious subject.

What is UV radiation and where does exposure take place?

There are three types of ultraviolet (UV) rays: UVA, UVB, and UVC. Because UVC rays do not get through our atmosphere, humans are only exposed to UVA and UVB rays, which are dangerous enough to your DNA—the powerhouse of all genetic information in each living cells.

Sunlight is the main source of UV rays. Other sources often include tanning lamps and beds. Sunlight contains both UVA and UVB and causes much more damage than you think because the thinning of ozone layers makes UV rays increasingly more powerful.

How does UV radiation/sunlight enhance skin cancer risk?

UVA rays can penetrate into your deeper skin layers and damage the structural components of your skin, such as connective tissues and blood vessels. This results in the loss of skin elasticity, wrinkling, and premature skin aging. Furthermore, UVA rays cause the development of some skin cancers. UVB rays are a more potent carcinogen because they can directly damage your DNA, leading to sunburn and skin cancer. So, as you see, there is no such a thing of safe UV rays.

How may UV radiation directly damage your DNA? At the molecular level, UV radiation can cause DNA lesions, distort DNA structure by forming bends or twists, and impede DNA repair. Consequently, these impairments to DNA hinder transcription and replication. DNA integrity and stability are essential to one’s life. That’s why direct exposure to UV radiation is harmful.

Two types of skin cancer (melanoma and non-melanoma) are both linked to sun exposure. The fact that non-melanoma skin cancers (including basal and squamous cell carcinoma) occur more frequent in outdoor than in indoor workers supports the notion that the accumulated life-time exposure to UV radiation plays a significant role in the development of these skin cancers.

Melanoma is a malignant skin cancer, though it is rare. In contrast to non-melanoma skin cancer, a higher incidence of melanoma is found in indoor compared to outdoor workers, which suggests that cancerous development might be associated with UV exposure at younger ages and/or occasional, intensive exposure to sunlight (e.g., on weekends or vacations).

Protect Yourself

Next time you are outdoors, make sure to protect yourself and your family (especially young kids) from sun damage. Protective practices include wearing a hat and sunglasses, covering exposed skin with clothing, staying in the shade, and applying sunscreen with an SPF of 15 or higher to body parts exposed to sun.

Take home message:

Exposure to UV radiation is a major risk factor for most skin cancers. UV rays can damage your DNA and cause skin cancer. Sun protection is your No. 1 defense against skin cancers.


Image credit: By SEPpics