What makes you more sensitive to the sun’s rays?
If you’ve ever had a sunburn, you know the pain of too much sun exposure.
Anytime you’re outside, you’re exposed to ultraviolet light from the sun, and those UV rays can damage your skin. Some people may be more sensitive to the sun than others, and they’re more likely to develop a sunburn or experience other consequences of too much solar radiation.
“Skin type and genetics play a role in how sensitive you may be to sun exposure,” explains Dr. Susan Massick, a board-certified dermatologist and associate professor of dermatology at the Ohio State University Wexner Medical Center in Columbus. “(For instance,) fair skin and (light or) red hair make you more susceptible to damaging ultraviolet rays and put you at higher risk for sunburn, sun damage and skin cancer.”
But any skin type can be sensitive to the sun.
Your skin type matters.
Sun sensitivity can vary as much as 100-fold from those who burn easily to those who don’t seem to burn at all, says Robert Alesiani, a clinical pharmacist and chief pharmacotherapy officer with TabulaRasa HealthCare Inc., a health care technology firm that aims to decrease adverse medication-related events, in New Jersey.
The factors behind this sensitivity include skin type and melanin as well as how your body responds to sun exposure.
“Based on the ability of the skin to tan when exposed to sunlight, we classify skin in six types: from Fitzpatrick type I, very light skin, burns but never tans, to Fitzpatrick type VI, very dark, never burns,” explains Dr. Mariano Busso, a board-certified dermatologist in private practice in Miami and Beverly Hills, California.
This scale is based on the amount of melanin, a pigment in your body — especially in the skin, hair and eyes — that absorbs sun radiation.
“Melanin acts like an umbrella over the cell nucleus, shading and protecting the DNA from the sun’s harmful radiation,” says Dr. Tanya Nino, a dermatologist and melanoma program director at the Center for Cancer Prevention and Treatment at Providence St. Joseph Hospital in Southern California.
People with less melanin — those with lighter skin — are more likely to burn because “their cells have less protection from damage,” she adds.
Quite simply, the darker your skin, the more protected you are from the harmful effects of UV radiation.
For many people, the longer you spend in the sun, the darker your skin becomes. This is because your cells produce more melanin as a protective response to repeated exposures to UV light, Alesiani explains. But tanning isn’t quite the same as actually protecting your skin with sunblock or avoiding sun exposure.
Sun sensitivity is also related to how well your cells can repair themselves after UV exposure, Busso says. “Sensitivity to the sun is a dynamic balance between damage prevention and repair,” he explains.
Chemicals can make you more sun sensitive too.
Some people are just more sensitive to the sun to begin with, but for others, exposure to certain chemicals can increase the chances of a sunburn or skin cancer.
These chemicals are “like gunpowder, and UV radiation is the match that causes the reaction to happen,” explains Dr. Bruce Robinson, a board-certified dermatologist in private practice and clinical professor of dermatology at Lenox Hill Hospital in New York City. “When UV light hits that chemical, it causes a reaction like an explosion in the skin, and you get damage.”
Types of photosensitivity
This are two types of this increased sensitivity, or photosensitivity: phototoxic and photoallergic.
Phototoxic reactions look and feel like a severe sunburn and occur within hours of exposure. “You can develop redness, swelling, even blistering from phototoxic reactions,” Massick says.
These reactions occur when direct exposure to UV light activates a photosensitizer — commonly a food or a medication you’re taking — and results in cell damage. They’re usually limited to sun-exposed areas, such as the face, the V of the neck and upper chest and the upper shoulders.
These reactions depend on the dose of sunlight, or how much sun you get and how long you’re exposed.
Photoallergic reactions look more like a rash than a regular sunburn and can include itchy patches and redness. They can also blister sometimes, Massick says.
These hypersensitive reactions are caused by the immune system responding to an exposure on the skin or ingestion of an allergen that induces an allergic reaction. These reactions can get progressively worse with each exposure.
Photoallergic reactions usually peak within 24 to 72 hours “but can take much longer for discoloration or post-inflammatory hyperpigmentation to resolve,” Massick notes. And as with any allergen, “you can develop a hypersensitivity reaction to an exposure that triggers an immune response.”
There are other factors that can lead to a photosensitive reaction as well. Here are five triggers:
Medical conditions
Photosensitivity is more common in people with certain autoimmune diseases, Massick says. “For autoimmune conditions, such as lupus and dermatomyositis, sun exposure can make the skin develop more redness, irritation and, in some cases, scarring.”
Other conditions can also cause severe sun sensitivity. These include:
— Xeroderma pigmentosum, a disease in which there is a genetic defect in the enzymes involved in damaged DNA repair, Busso says. Massick adds that “the cell damage from UV exposure cannot be repaired, and accumulated sun exposure will lead to early onset of aggressive types of skin cancer.”
— Basal cell nevus syndrome, a rare inherited disorder that can impact a range of body systems, in addition to causing pits in the palms and soles and a high likelihood of developing basal cell skin cancer.
—Porphyria, a liver disease that results in the accumulation of porphyrins, pigments that are involved in the production of hemoglobin.
— Sun allergies. Polymorphous light eruption, or PMLE, actinic prurigo and solar urticaria are all conditions in which sun radiation “causes a change in the skin that is recognized by the immune system and triggers a skin rash,” Busso explains.
People with these conditions must be careful when they head outside because their risk of cancer can be very high in some cases. But this isn’t always easy to do. “You can’t completely avoid the sun all the time,” Massick says. “The focus is on minimizing sun exposure, being smart about when it’s safe to be outdoors and being consistent with sun protection.”
Medications
Certain medications can make it far more likely that you’ll burn when exposed to sunlight.
Drugs that are known to increase sun sensitivity include:
— Antibiotics, including drugs in the tetracycline family (doxycycline, tetracycline, minocycline, demeclocycline), fluoroquinolones (ciprofloxacin, levofloxacin, norfloxacin) and sulfonamides, or sulfa drugs, such as sulfamethoxazole, sulfadiazine, sulfisoxazole and sulfinpyrazone.
— Nonsteroidal anti-inflammatory drugs, such as ibuprofen, ketoprofen and naproxen.
— Antihistamines, such as diphenhydramine (Benadryl), cetirizine (Zyrtec) or loratadine (Claritin).
— Diuretics, including hydrochlorothiazide and furosemide, which may be used to treat high blood pressure, edema, heart failure and other conditions where fluid accumulation is an issue.
— Hormones, such as estrogen, progesterone and their derivatives. These include oral contraceptives and postmenopausal hormone replacement therapies.
— Systemic retinoids, such as isotretinoin, which may be used to treat cystic acne. Examples include tretinoin (Retin-A), adapalene (Differin) and tazarotene (Tazorac).
— Phenothiazines, such as prochlorperazine, chlorpromazine, promethazine, thioridazine and trifluoperazine. These medications are used as antipsychotics in the treatment of certain mental health disorders.
— Cancer immunotherapies, such as vemurafenib, which is used to treat some skin cancers.
— Oral diabetes drugs, such as sulfonylureas and metformin. Dr. Matthew Lomelí, a board-certified family physician and medical director of telehealth, patient access and the patient service center at Altamed Health Services in Southern California says, “The risk is low, and if you are concerned, you should discuss with your physician.”
— Oral hypoglycemics, such as glipizide, glyburide and chlorpropamide.
— Tricyclic antidepressants, such as amitriptyline, nortriptyline, doxepin, desipramine and imipramine.
— Topical treatments for psoriasis, such as Neutrogena T/Gel shampoo, Denorex, DHS Tar Shampoo, Zetar shampoo and emulsions.
— Herbal drugs, such as St. John’s wort, which is sometimes used to treat depression and anxiety.
Foods
Consuming certain foods can increase sun sensitivity, as compounds within these foods can cause the skin to react more to the sun’s rays. Ones to watch out for include:
— Carrots.
— Celery.
— Citrus fruits, such as limes.
— Fennel.
— Figs.
— Wild dill.
— Wild parsley.
— Wild parsnips.
These reactions are sometimes referred to as phytophotodermatitis, Massick explains. “Phyto” means plants, “photo” refers to UV light and “dermatitis” refers to the rash that occurs with exposure to plants that contain a chemical called furocoumarin.
“Furocoumarins become activated when exposed to the UV light, and you develop a skin rash wherever your skin comes into contact with the chemical,” Massick says. All of the foods listed above contain furocoumarins.
Busso notes that phototoxic reactions occur in two phases. “In the first phase, there is inflammation, which lasts days, followed by hyperpigmentation, which lasts months. Treatment of the inflammatory phase is based on the application of corticosteroids,” he explains.
The second, hyperpigmented phase “resolves without treatment within a few months,” Busso says. During that time, your doctor will advise you to avoid the sun and to cover up completely if you do head outdoors. If persistent, there are bleaching creams your dermatologist can prescribe.
Perfumes and essential oils
Certain perfumes can take a toll on your skin, Massick says. These products “often contain the chemical sensitizer bergapten,” which can augment the effects of the sun, he explains.
“When this chemical comes in contact with the skin and is exposed to the long-wave UVA radiation, a phototoxic reaction can occur,” Busso adds. “This chemical is present in bergamot lime, which has been part of many fragrances, perfumes, cosmetics and toiletries.”
Musk and essential oils like lavender, rosemary and sandalwood, for instance, can make your skin more reactive to the sun.
Skin care products
Lomelí says that retinol, a vitamin A derivative “that is sometimes found in night creams or anti-aging products is similar to tretinoin, a prescribed medication used to treat acne and other skin conditions.”
Certain skin care products that include retinol, specifically those used to treat acne or those designed to exfoliate the top layer of skin cells, can drastically increase your sun sensitivity. Check for ingredients such as:
— Alpha-hydroxy acids, or AHAs, such as glycolic acid.
— Beta-hydroxy acids, or BHAs, such as salicylic acid.
— Tretinoins, such as Retin-A.
Each of these agents strips the outer layer of the skin, the stratum corneum, which reveals an underlying layer of skin that’s more sensitive to the sun. Plus, the chemical benzoyl peroxide, which is in many over-the-counter acne products, can also cause photosensitivity.
When shopping for skin care products, Nino recommends being on the lookout for skin products that contain retinoids, which cause photosensitivity and lead to burning more easily. “Many formulations labeled as ‘anti-aging’ will have some form of a sun-sensitizing agent,” she explains.
Reactions aren’t universal.
While certain things can increase sun sensitivity, not everyone who takes a certain drug or uses a particular product will experience photosensitivity, notes Dr. D’Anne Kleinsmith, a board-certified dermatologist at Beaumont Hospital, Royal Oak, and the Midwest Center for Dermatology and Cosmetic Surgery in Farmington Hills, Michigan.
And even if you do have a photosensitive reaction on one occasion, that doesn’t guarantee that you will again or every time you use or ingest that substance.
Still, if you have a reaction, it’s important to determine what’s causing it, Massick says. “These reactions are temporary and will resolve, but the key is to identify the culprit,” she explains. “If the culprit can’t be identified or, in the case of long-term medications, can’t be discontinued, then the focus should be on minimizing sun exposure and maximizing sun protection.”
How to be sun safe
There are several ways to be sun safe that limit your exposure to damaging UV rays and reduce your chances of developing a sunburn or aging prematurely.
Whether you’re using or consuming any photosensitizing ingredients or not, you should try to limit your exposure to the strongest rays of the sun, which shine down between 11 a.m. and 3 p.m. Kleinsmith recommends completing outdoor activities in the early morning or the late afternoon.
Other strategies involve care with covering and protecting skin.
Cover up.
Even while avoiding the most intense sunlight, it’s still important to wear long sleeves, a hat and other clothes that help shade your skin from the sun’s harsh rays. “The easiest thing to do is wear sun-protective clothing, a hat, sunglasses and seek shade,” Nino says.
Lomelí adds that dark clothing is better than lighter clothing and that accessories like hats and umbrellas can also be very helpful in shading you from the sun.
Use plenty of high-quality sunscreen.
Take extra precautions before spending time in the sun. Choose a water-resistant sunscreen that protects against the sun’s UVA and UVB rays. Look for the words “broad spectrum” and a sun-protection factor, or SPF, of 30 or greater.
Busso notes that “sunscreens should contain at least one of these ingredients in order to protect against UVA radiation: titanium dioxide, zinc oxide, avobenzone, oxybenzone, sulisobenzone or ecamsule.”
How you apply sunscreen matters too. While any protection is better than none, “creams and lotions work better than sprays,” Kleinsmith notes. Apply a sunscreen with SPF 30 every day — or SPF 50 or more if you’re going to the beach or golfing — 20 to 30 minutes before you go outside. And reapply it every hour and a half to two hours while you’re outdoors. That timeline condenses if you’re swimming or sweating because liquid can wash off the sun-protective ingredients.
What’s more, most people don’t put on enough sunscreen, so apply at least a shot glass full (1 ounce) each time. If you have the same bottle of sunscreen on Labor Day that you started with on Memorial Day, you definitely aren’t using enough.
Lomelí stresses that you should use sunblock every day, “even if you work indoors.” And, the fairer your skin, the more frequently you should apply. “Sun damage appears about 20 years later, so do your future self a favor and cover up,” he advises.
Consider a supplement.
If you’re going to the beach and you’re sun-sensitive, Kleinsmith recommends taking an oral antioxidant supplement like Heliocare in the morning. This supplement contains an extract of Polypodium leucotomos, a tropical fern rich in antioxidant compounds that protect the skin from free radical damage. Other antioxidants, such as vitamin B6 and beta-carotene, have been shown to increase tolerance to UV rays, Busso adds.
“It’s another adjunctive treatment in the skin-protection program,” Kleinsmith says. While such supplements should never replace sunblock, they may help add an edge of protection, increasing your odds of preventing a painful sunburn or unexpected skin damage from ruining your summer fun.
However you decide to protect yourself, Nino says you shouldn’t live in fear of the sun because you have some measure of control over how exposed you are. “You can enjoy the outdoors with proper sun protection and awareness of these factors that increase your susceptibility to sunburn,” she notes.
Top factors that make you more sensitive to the sun:
== Medical conditions.
— Medications.
— Foods.
— Perfumes and essential oils.
— Skin care products.
More from U.S. News
What to Ask a Dermatologist About Skin Diseases
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Surprising Factors That Increase Sun Sensitivity originally appeared on usnews.com
Update 07/19/23: This story was previously published at an earlier date and has been updated with new information.
