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Sun Exposure May Trigger Auto Immune Disease in Women

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Ultraviolet (UV) radiation from sunlight may be associated with the development of certain autoimmune diseases, particularly in women, according to a study by researchers at the National Institute of Environmental Health Sciences (NIEHS), part of the National Institutes of Health.

“This study found that women who lived in areas with higher levels of UV exposure when they developed an autoimmune muscle disease called myositis were more likely to develop the form known as dermatomyositis, which weakens the muscles and causes distinctive rashes, instead of the form called polymyositis that does not have a rash,” said Frederick W. Miller, M.D., Ph.D., chief of the Environmental Autoimmunity Group, Program of Clinical Research, at NIEHS. “Although we have not shown a direct cause and effect link between UV exposure and this particular autoimmune disease, this study confirms the association between UV levels and the frequency of dermatomyositis that we found in a previous investigation,” said Miller.

The study, published in the August issue of Arthritis & Rheumatism, is also the first to evaluate and find a possible UV radiation association in autoimmune diseases in women.

According to Miller, women are more likely than men to develop many autoimmune diseases, but the reasons for this have not been clear. “We only found the association between UV exposure and dermatomyositis in women and not in men, and it could be that inherent differences in how women and men respond to UV radiation may play a role in the development of certain autoimmune diseases,” said Dr. Miller. Miller also noted that other researchers have shown that female mice develop more skin inflammation after UV light exposure compared to male mice and these effects may be related to the new findings in dermatomyositis.

The study was designed to determine if there was a relationship between the level of UV exposure at the onset of the disease and the type of myositis and autoantibodies that people developed. Dermatomyositis and polymyositis are the two major forms of myositis and both are considered autoimmune diseases, in which the body’s immune system attacks muscle or skin and sometimes other tissues. Dermatomyositis is typically accompanied by a distinctive reddish-purple rash on the upper eyelids or over the knuckles and is often made worse with sun exposure.

To conduct the study, the NIEHS researchers collaborated with myositis centers across the country that had seen 380 patients who had been diagnosed with dermatomyositis or polymyositis and determined their autoantibodies. “Patients with autoimmune diseases make a variety of autoantibodies that are unique to different conditions. One autoantibody specifically associated with dermatomyositis is called the anti-Mi-2 autoantibody and we know from our previous research that UV radiation increases levels of the Mi-2 protein that this autoantibody binds to,” said Miller.

In addition to finding an association between the level of UV radiation and the proportion of women who developed dermatomyositis compared to polymyositis, the researchers found an association between UV levels and the proportion of women with the anti-Mi-2 autoantibody. “More research is clearly needed to understand the potential links between UV radiation and the development of autoimmune diseases and autoantibodies in women,” said Miller.

“While the causes of autoimmune diseases are not known, we suspect from emerging research that they develop after one or more environmental exposures in genetically susceptible people,” said NIEHS Director Linda Birnbaum, Ph.D. “This study adds UV radiation to the growing list of environmental exposures possibly important in the development of autoimmune diseases.”

Source: National Institute of Environmental Health Sciences (NIEHS), July 30, 2009

Hormone Replacement Therapy (HRT) and Its Effects on Skin Appearance

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For many women, hormone replacement therapy (HRT) can alleviate the physical symptoms associated with the change of life. But despite the initial hype generated by post-menopausal women who noticed a marked improvement in their skin’s appearance while on HRT, dermatologists argue that scientific studies of estrogen do not show definitive improvements for skin rejuvenation of photodamaged skin and the potential risks when used long-term outweigh any potential skin benefits.

At the American Academy of Dermatology’s Summer Academy Meeting 2009 in Boston, dermatologist Margaret E. Parsons, MD, FAAD, assistant clinical professor of dermatology at the University of California at Davis in Sacramento, reviewed studies that demonstrate mixed results when examining whether or not estrogen improves the appearance of the skin and why patients should opt for tried-and-true cosmetic therapies instead.

“Based on the research conducted thus far, it does not appear that topical or oral estrogens are a viable long-term solution for improving sun-damaged or aging skin,” said Dr. Parsons. “In my practice, I do not prescribe estrogens for skin rejuvenation because of the lack of consistent data to support their use and the known risks of prolonged estrogen therapy – including an increased risk of breast cancer.”

Estrogens are a group of hormones that play a key role in regulating many aspects of a woman’s overall health, including reproduction. Certain parts of the body contain cells that are more receptive to the effects of estrogen than others, including the face. Dr. Parsons noted that estrogens benefit the skin in many ways, including an increase in collagen content, water retention and elasticity.

During pregnancy when estrogen levels are at their highest, women experience thicker hair and glowing skin. On the other hand, post-menopausal women may
notice that their skin does not have the same elasticity as it once did and that it is drier than normal.

In order to treat the most common symptoms associated with menopause – including hot flashes, mood swings and vaginal changes – physicians often prescribe hormone replacement therapy (HRT) to boost the body’s estrogen levels that drop dramatically during this change of life. However, when the results of the Women’s Health Initiative (WHI) study were announced in 2002, the way HRT was viewed to treat post-menopausal women changed significantly. For example, the WHI study found that women on long-term HRT could be at an increased risk for breast cancer and that the overall health risks of this therapy could outweigh the possible benefits. From that point on, HRT was prescribed more conservatively with lower dosing options and individualization based on each woman’s own health history.

Since there were reports of some women on HRT noticing an improvement in their skin, studies were conducted to determine if these results could be validated. Dr. Parsons explained that results of multiple studies examining the relationship between estrogens and skin improvement were inconclusive.

For example, one study examined whether low-dose hormone therapy improved aging skin in 485 women who were on average five years post-menopausal. Published in the September 2008 issue of the Journal of the American Academy of Dermatology, the study concluded that estrogen supplementation did not provide any significant improvement in sun-damaged skin.

“Although this study found no obvious skin benefits in this particular group of women, another study that looked at women who began HRT at the onset of menopause – and did not wait to start treatment like the other group – did experience noticeable improvements in their skin,” said Dr. Parsons. “These
studies pose unanswered questions as to the timing and duration of prescribing HRT to produce skin benefits. For this reason, the jury is still out as to whether estrogens can be effective for aging skin.”

In addition, another study showed that applying topical estrogen to sun-damaged facial skin and sun-protected skin on the hip of post-menopausal women resulted in stimulated collagen production and less wrinkling in the sun-
protected hip skin, but no noticeable improvement in the sun-damaged facial skin.

Dr. Parsons added that more research will likely continue in the future to examine the possible benefits of estrogen for improving aging skin. Until then, she stressed that there are many effective therapies that dermatologists regularly use to address the common signs of aging – including retinoids, alpha-hydroxy acids and other topical therapies, as well as chemical peels, lasers, botulinum toxin and skin fillers, to name a few.

“The best advice I can offer my patients to improve their overall skin health is to wear sunscreen with a sun protection factor (SPF) of at least 30, don’t smoke and use a topical retinoid,” said Dr. Parsons. “When it comes to minimizing the cumulative effects of sun damage, an ounce of prevention really does go a long way.”

Stay Healthy in Hot Weather

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Some 200 people in the US die each summer from health problems caused by hot weather, and this number is doubled when the summer is exceptionally hot. Here are three major hot weather threats that can be moderated, or avoided completely.

Heat cramps warn of dehydration and muscular deprivation of needed oxygen. The problem can be solved by drinking cool water, stretching, and light massage of the affected areas.

Heat Exhaustion is apparent when the body temperature is seriously elevated, often above 103 degrees F, and weakness, lethargy, loss of concentration, headache and nausea follow. Judgement can be affected, and the solution is to choose a cool spot, take of excess clothing, drink cool fluids, and apply any available ice packs.

Heat stroke can affect older people who stay at home without air-conditioning. Other victims include men who exercise during hot weather. Weakness and confusion can create delirium, stupor, coma and seizures, so heat stroke should be recognized as a real medical emergency, where survival depends on immediate treatment in a hospital.

Try the following to avoid hot weather health problems:

  • Hydrate: drink 10-12 cups of water daily, more if exercise is involved
  • Stay cool: move into a room with a fan or air-conditioning
  • Stay out of the sun, particularly midday sun, and wear light, loose-fitting clothes
  • Avoid exercising in hot or humid conditions

Source: Harvard Men’s Health Watch, August, 2008

Risk of Type 1 Diabetes in Children Related to Vitamin D and Sun

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Researchers have found that the risk of Type 1 diabetes in children may be strongly associated with Vitamin D and exposure to sunshine.

Low incidence of type 1 diabetes was noted in people living in equatorial regions, while higher incidence was noted in populations at higher latitudes where sunlight was scarcer.

Photosynthesis of vitamin D3 is set in motion by ultraviolet exposure, while this form of vitamin D is also available through diet and supplements. "This is the first study, to our knowledge, to show that higher serum levels of vitamin D are associated with reduced incidence rates of type 1 diabetes worldwide," said Cedric F. Garland, Dr. P.H., professor of Family and Preventive Medicine in the UCSD School of Medicine, and a member of the Moores UCSD Cancer Center.

About 1.5 million Americans cope with type 12 diabetes every day, and type 1 diabetes ranks second only to asthma as the most chronic disease among children. Type 1 diabetes is diagnosed in some 15,000 Americans each year, and causes blindness and kidney failure in youth and middle age.

"This research suggests that childhood type 1 diabetes may be preventable with a modest intake of vitamin D3 (1000 IU/day) for children, ideally with 5 to 10 minutes of sunlight around noontime, when good weather allows," said Garland. "Infants less than a year old should not be given more than 400 IU per day without consulting a doctor. Hats and dark glasses are a good idea to wear when in the sun at any age, and can be used if the child will tolerate them."

Even after allowing for the fact that equatorial regions will have lower per capita healthcare expenditures than more developed countries, the association of UVB irradiance to incidence of type 1 diabetes remained strong. The researchers created a graph with a vertical axis for diabetes incidence rates, and a horizontal axis for latitude. The latitudes range from -60 for the southern hemisphere, to zero for the equator, to +70 for the northern hemisphere. They then plotted incidence rates for 51 regions according to latitude. The resulting chart was a parabolic curve that looks like a smile.

In the paper the researchers call for public health action to address widespread vitamin D inadequacy in U.S. children.

"This study presents strong epidemiological evidence to suggest that we may be able to prevent new cases of type 1 diabetes," said Garland. "By preventing this disease, we would prevent its many devastating consequences."

The study was published June 5, 2008 in the online version of the scientific journal Diabetologia.

Protecting Yourself from the Sun to Avoid Skin Cancer

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Before leaving home for a day of outdoor activity, take appropriate precautions to ensure that your and your family’s skin is well-protected, as the majority of all skin cancers are caused by the sun.

According to Susan Chon, M.D., assistant professor of dermatology at The University of Texas M. D. Anderson Cancer Center, a sunscreen with an SPF of at least 30 is a good choice for most people. One ounce of sunscreen (enough to fill a shot glass) is considered sufficient to properly cover sun-exposed areas. To get the most protection from sunscreen, generously reapply throughout the day. This is especially important because factors such as humidity, perspiration and uneven product application can cause sunscreen to lose its effectiveness.

Sun Protection Checklist
Chon recommends gathering the following items before heading outdoors.

  • Sunscreen with SPF 30 or greater
  • Lip balm with SPF 30
  • Hat with a brim or cap
  • Long-sleeved shirt (preferably sun protective clothing)
  • Sunglasses with UV protection

"These are great items to keep handy in your bag to prepare for the sun as it intensifies throughout the day," Chon said.

Application Time Line
Chon suggests the following time line for when to best use these items.

Morning: 8 – 10 a.m. Apply sunscreen with SPF 30, at least 30 minutes before sun exposure.
Reapply sunscreen every two hours.
Wear a hat, sunglasses and lip balm.

Midday: 11 a.m. – 2 p.m. (hottest time of the day)
Seek shade for extra protection.
Wear a long-sleeved shirt with a hat and sunglasses.
Reapply sunscreen and lip balm every two hours.

Afternoon: 3 – 5 p.m.
Keep wearing a hat and sunglasses.
Reapply sunscreen and lip balm every two hours.

"Remember, if you are sweating or swimming, you may need to reapply more often," Chon said. Avoid reflective surfaces such as water, sand, snow and concrete. "You can burn from indirect exposure to the sun, too," Chon said.

According to the American Cancer Society, more than one million cases of basal cell or squamous cell cancers, the most common types of skin cancer, occur annually. The most serious form of skin cancer is melanoma, of which more than 60,000 people are expected to be diagnosed in 2008.

Source: University of Texas M. D. Anderson Cancer Center

Tans Fade but Wrinkles are Forever – Slip, Slop, Slap

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Sun damages skin—period.
The obvious trick in summer is to balance exposure to sun with protection from the harmful rays that cause skin damage and can lead to cancer. These rays are known as UVA and UVB rays, with UV standing for Ultra Violet.

Australian health authorities, alarmed by the skyrocketing rise of minor skin cancers and deadly skin melanomas have instituted a health campaign with the tag line: SLIP (on a shirt), SLOP (on sunscreen), and SLAP (on a hat).

Lets briefly look at the elements of the campaign.
SLOP: Many people tend to confuse the terms "sunblock" and "sunscreen". Sunblock fully blocks the rays of the sun and consists of such "blocks" as titanium and zinc oxides. They are extremely effective in blocking sunlight, but they also are colored and leave the wearer appearing like a character on the canvas of "Women of Avignon" by Picasso. Furthermore, they need to be reapplied after only a few hours.

Two sunscreens that have hit the stores this year, Heliolex and Anthelios SX provide significant protection against UVA (80%) and UVB (90%) for up to five hours after application. Helioplex is sold by Neutrogena as UltraSheer. They go on easily, need to be reapplied less frequently than sunblocks, and are invisible.

SLIP: Nothing blocks the sun better than clothing, and when the sun is blazing, make sure you put a shirt on to protct your back and shoulders.

SLAP: You don’t have to look like a kangaroo hunter, but the more you can put your face in shadow, the less harmful rays your skin will accumulate.
And yes, you can get a fine tan with all of the above.
Drill this into your kids:

SLIP on a shirt
SLOP on sunscreen
SLAP on a hat

Summertime Survival Tips: Water Intake

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It’s summertime and you’ve forgotten to bring along your water bottle for your afternoon hike. Should you go back and get it, or keep hiking and worry about it later.
Go back.
The rule of thumb is eight—eight glasses of fluid a day per person, increasing fluid intake for exercise, hot weather, high altitude or low humidity.

If you hike without adequate hydration, you have a greater chance of developing fatigue, headaches and general irritability.
Drink before you get thirsty, and drink until your urine is only slightly yellow. Water is preferable over juices and sports drinks if you’re trying to watch calories.

The US national Research council suggests that another rule of thumb— match one ml of water for every calorie consumed. In other words, if you eat 3,000 calories worth of food, you have to drink 3,000 milliliters of water.

 

Remember that if you don’t want to wake up at night for a bathroom stop, don’t drink within two hours of going to sleep. Also, alcohol and caffeine have diuretic side-effects—they increase urine output.

Mice Use Less Sunscreen – Substitute Coffee and Exercise Instead

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Who would have guessed that coffee and exercise induce the formation of cells that block sunrays? But they do–at least in mice.

As reported in the Proceedings of the National Academy of Science, hairless mice who were fed high doses of caffeine, and exercised on their running wheels, showed an increase in the cells which protect against sunburn.

There have been no human studies to date, so you may wish to continue your sunscreen, hats and shirts before switching to double espressos on the beach.

Source: Proceedings of the National Academy of Science, "Voluntary exercise together with oral caffeine markedly stimulates UVB light-induced apoptosis and decreases tissue fat in SKH-1"