Friday, May 25, 2012

Children and Sun Safety

A single blistering sunburn in childhood or adolescence doubles a person's chances of developing melanoma skin cancer later in life.  Other types of skin cancer, basal cell carcinoma and squamous cell carcinoma, are directly related to long-term sun exposure.  Children often spend a good part of their day playing outdoors in the sun, especially during the summer.  The development of skin cancer, as well as premature skin aging and eye damage, are reasons that measures to protect the body from harmful sun rays should be started early in life.
What is sunburn?  Sunburn is a reaction to skin exposure to ultraviolet (UV) radiation which are the invisible rays that are part of sunlight.  Sunlight contains three types of ultraviolet rays: UVA, UVB, and UVC. UVA rays make up the majority of our sun exposure since they freely pass through the ozone layer.  UVB rays are blocked to a large degree by the ozone layer, but most cases of sunburn, as well as the development of melanoma, are due to excessive exposure to UVB radiation.  UVC rays are more dangerous than the other two types but, fortunately, are blocked from reaching the earth by the ozone layer.

How well do sunscreens work? 
Sunscreens contain chemicals that help prevent ultraviolet (UV) radiation from reaching the skin.  There are a number of effective sunscreens on the market. The best sunscreens provide "broad spectrum" coverage, meaning that they block both UVA and UVB rays.  When shopping, you should look for sunscreen with a Sun Protection Factor (SPF) of 15 or higher.  SPF indicates how long it will take for UVB rays to redden skin when using a sunscreen, compared to how long skin would take to redden without the product.  Sunscreen should be applied even on cloudy days since UV rays can penetrate clouds.

How should sunscreen be applied? 
The chemicals in sunscreens have caused skin reactions in some children.  It is best to test a small area of the skin before applying them to the entire body.  The appropriate application and re-application of sunscreen is equally important as its SPF rating.  Sunscreen should be applied liberally at least 20 to 30 minutes before exposure to the sun, making sure that exposed areas are well covered, and rubbed in completely.  As a guide, the appropriate amount for an adult-sized body is approximately one ounce (the amount in shot glass).  Keep in mind that no sunscreens are truly waterproof, and need to be reapplied every one and a half to two hours, particularly if the child spends a lot of time in the water.  In children who are prone to sunburn, use sunscreen with a higher SPF rating, although there is little additional benefit in using one higher that 50+.  For maximum protection against UV rays, particularly on highly sensitive areas such as the nose or tops of ears, a sunblock may be preferable to sunscreen.  These contain physical agents, such as titanium dioxide or zinc oxide that completely absorb UV rays.  Sunblocks remain opaque on the skin and some even come in colors that kids enjoy.

Besides sunscreen, what can be done to avoid sunburn?
  The American Academy of Pediatrics (AAP) recommends that babies younger than 6 months of age should be kept out of direct sunlight.  When possible find shade under a tee, umbrella, or the stroller canopy to shade the infant.  If adequate clothing and shade are not available, sunscreen can be used on small areas of an infant's body, such as the face and the backs of the hands.  For children over the age of 6 moths the AAP offers the following recommendations to avoid sunburn in children:
  • Select clothes made with a tight weave - they protect better than clothes with a looser weave.  If you're not sure how tight a fabric's weave is, hold it up to see how much light shines through.  The less light, the better.
  • Wear a hat or cap with a brim that faces forward to shield the face.
  • Limit sun exposure between 10:00 am and 4:00 pm, when UV rays are strongest.
  • Set a good example. You can be the best teacher by practicing sun protection yourself.
What about eye protection from the sun???  UV radiation can be damaging to the eyes as well as the skin.  Cataracts, skin cancer, and a benign growth on the surface of the eye known as a pterygium have all be associated to excessive UV exposure.  Sunglasses rated to block 99 to 100 percent of both UVA and UVB will offer protection against these conditions.  Sunglasses should be sized appropriately for the child's face.  A wide-brimmed hat will also help to reduce the amount of UV radiation that reaches the eyes.

Are tanning booths a safer alternative to "laying out" in the sun?  Absolutely not! The bulbs in tanning booth can produce over 10 times as much UVA radiation as the sun.  Studies have shown that people who use tanning booth have a higher rate of occurrence of squamous cell and basal cell carcinoma as well as skin melanoma.  Several authorities have advocated making it illegal for parents to let kids under 18 use tanning booths.  The bottom line is that there is no such thing as a "healthy tan".  Whether it came from a tanning booth or from sun exposure, tans are the result of exposure to harmful UV radiation on the skin.

Friday, May 18, 2012

Medical "Miracles"

Perform a google search on "the most important medical breakthroughs" and you are likely to find items such as "Man Walks Again after Being Chopped in Half" or "Teen lived 118 days without Heart".  But in terms of having an effect on decreasing the burden of disease and increasing longevity, there are three much less exotic medical breakthroughs in medical history that stand out.

The Development of Immunizations - Historically, infectious diseases have been one of the primary causes of death.  Epidemics involving smallpox, bubonic plague, and influenza were responsible for killing millions of people in the past. Smallpox alone is estimated to have caused up to 500 million deaths.  This changed dramatically following the discovery of vaccines by Edward Jenner.  In 1796, Jenner developed a method to immunize people against smallpox by exposing them to a related virus called cowpox.  This process became known as vaccination from the Latin word "vacca" that means cow.  As a result of worldwide smallpox vaccinations, the World Health Organization announced in 1979 that smallpox was officially eradicated.  Today, numerous vaccines are available to prevent diseases caused by bacteria as well as viruses.  These include immunizations against tetanus, typhoid, cholera, influenza, shingles, whooping cough, polio, Hepatitis A & B, measles, mumps, rubella, chickenpox and pneumococcal disease.

The Establishment of the Germ Theory of Disease - In the 1870s, Louis Pasteur and Robert Koch established the germ theory of disease.  This theory proposes that microorganisms, such as bacteria and fungi, are the cause of many diseases.  Prior to this time, most doctors believed that living organisms responsible for disease could arise directly from nonliving material, a process known as spontaneous generation.  The finding of tiny organisms contained in tooth plaque, spittle, and feces was actually first discovered two hundred years earlier by a Dutch salesman named Anton Leeuwenhoek when he studied various fluids through a microscope.  Knowledge of the germ theory has led to important means of preventing disease, such as water purification, food preservation, sterilization of surgical instruments, quarantining of infectious patients, and even hand washing to prevent transmission of disease.  Modern sanitation methods owe their development to the germ theory and today are responsible for preventing millions of cases of infectious disease throughout the world.

The Discovery of Penicillin - The discovery of penicillin in 1928 by the Scottish bacteriologist, Sir Anthony Fleming marked the time when a means of fighting back against infectious disease emerged.  The story of its discovery involves a lab assistant who left a window open and spores of a blue-green mold (Penicillium notatum) landed in a petri dish containing Staph bacteria.  The following day, Fleming noticed that a substance produced by the mold, now called penicillin, had stopped the growth of the bacteria.  Although the medical use of penicillin was delayed by production issues and confirmation of its effectiveness in treating human disease, by World War II penicillin made a major difference in the number of deaths and amputations caused by infected wounds.  The discovery of penicillin and the successful treatment of once fatal infections and diseases eventually led to the development of a variety of other antibiotics that are in common use today.

Other medical breakthroughs could arguably be considered to be as the important as the ones listed above.  The development of x-rays, for example, has led to an array of imaging methods to study the human body non-invasively, such as CT and MRI scans.  Once effective anesthetics were found, the field of surgery blossomed since operative pain was no longer a limiting factor in developing more complex and intricate surgical procedures.  The findings of the Framingham Heart Study that clarified the relationship between risk factors such as high blood cholesterol, hypertension and smoking and the development of cardiovascular disease would also have to be considered one of the most important medical breakthroughs of the 20th century.

While other advances in medicine may be more dramatic, the three discoveries listed above will likely never be surpassed in the number of lives saved.  Ironically, the advances in health from some of these "miracles" are now being compromised due to indiscriminate prescribing of antibiotics leading to resistant organisms as well as a backlash against providing immunizations.

Monday, May 14, 2012

What’s so bad about Trans Fats?

Since 1993, food labels have included information on saturated fat and cholesterol.  In 2006, the U.S. Food and Drug Administration also began requiring information on trans fat.  What are trans fats and why is an understanding of it important to our health?

What is trans fat?  Trans fat is produced when manufacturers add hydrogen to vegetable oil, a process called hydrogenation.  This process turns liquid oils into solid fats like shortening and hard margarine.  A small amount of trans fat is found naturally, primarily in dairy products, some meat, and other animal-based foods.

Why have trans fats been used in food preparation?  Companies like using trans fats in their foods because they give foods a desirable taste and increase their shelf life.  Many restaurants and fast-food outlets use trans fats to deep-fry foods because oils with trans fats can be used many times in commercial fryers.

What's wrong with eating trans fat?  Many doctors consider trans fat to be more harmful to our health than saturated fat or cholesterol.  Most people are aware that consumption of saturated fat and dietary cholesterol raises low-density lipoprotein (LDL), or "bad" cholesterol levels.  An elevated LDL level in the bloodstream increases the risk of developing coronary heart disease (CHD).  Like saturated fats, trans fats raise LDL "bad" cholesterol, but they also lower HDL "good" cholesterol.  This further increases the risk of developing "hardening of the arteries" (arteriosclerosis) and heart disease.

What foods contain trans fats?  Trans fat can be found in vegetable shortenings, some stick margarines, and other foods made with or fried in partially hydrogenated oils. Foods with the highest amount of trans fat include:
  • cookies, crackers, cakes, muffins, pie crusts, pizza dough, and breads such as hamburger buns

  • pre-mixed cake mixes, pancake mixes, and chocolate drink mixes

  • foods, including donuts, French fries, chicken nuggets, and hard taco shells

  • snack foods, including chips, candy, and packaged or microwave popcorn

  • frozen dinners
Is any amount of trans fat safe to eat?  The American Heart Association recommends limiting the amount of trans fats you eat to less than 1 percent of your total daily calories.  With a 2,000 calorie a day diet, no more than 2 grams, or about 20 calories should come from trans fat.

How can I limit my intake of trans fats?  Here are some practical tips you can use every day to keep your consumption of saturated fat, trans fat, and cholesterol low while consuming a nutritionally adequate diet.
  • Check the Nutrition Facts panel to compare foods and choose foods lower in saturated fat, trans fat, and cholesterol.

  • Choose alternative fats. Replace saturated and trans fats in your diet with monounsaturated and polyunsaturated fats.  These fats do not raise LDL cholesterol levels and have health benefits when eaten in moderation.  Sources of monounsaturated fats include olive and canola oils.  Sources of polyunsaturated fats include soybean oil, corn oil, sunflower oil and foods like nuts and fish.

  • Choose vegetable oils (except coconut and palm kernel oils) and soft margarines (liquid, tub, or spray) more often because the amounts of saturated fat, trans fat, and cholesterol are lower than the amounts in solid shortenings, hard margarines, and animal fats, including butter.

  • Eat more fish.  Most fish are lower in saturated fat than meat.  Some fish, such as mackerel, sardines, and salmon, contain omega-3 fatty acids, which are being studied to determine if they offer protection against heart disease.

  • Choose lean meats, such as poultry without the skin, lean beef and pork, with visible fat trimmed.

Thursday, May 3, 2012

Lyme Disease, recognition, treatment, and prevention

Statistics from the CDC indicate that there has been a progressive rise in the number of cases of Lyme disease diagnosed. It is unclear whether this increased incidence is because of greater awareness and recognition of the disease among physicians, or whether more people are becoming infected. In 2010, 94% of Lyme disease cases were reported from 12 states, mostly in the northeastern U.S., near the town where the disease gets its name-Lyme Connecticut.

What causes Lyme disease? Lyme disease is an infection caused by a type of bacteria known as Borrelia burdorferi. The infection is most often acquired from the bite of an infected deer tick, also known as a black-legged tick. Ticks that spread the infection are in the nymph stage of their life cycle and are quite small when compared to the adult ticks. The infection is spread when a young tick feeds on an infecte bcv  ./,d animal, taking Borrelia bacteria into its body. If the tick then feeds on a human, the bacteria can be passed along to its new host. There is no evidence that Lyme disease can be passed on from person-to-person.

What is the first sign that someone may have Lyme disease? Lyme disease produces different manifestations at different times during the course of the illness. The first sign of an infection is usually a rash called erythema migrans (EM). This is a circular rash that develops at the site of the tick bite. This rash occurs in approximately 70-80% of those infected, appearing anywhere from a few days to a month after the tick bite. EM gradually expands over a period of several days and can reach up to 12 inches in diameter. Sometimes the center of rash clears, resulting in a "bull's eye" appearance.

What symptoms are associated with Lyme disease? Along with the rash, most people with early Lyme disease develop symptoms such as fatigue, chills, fever, headache, muscle and joint aches. Red rings can develop at the site of tick bites for reasons other than Lyme disease. Localized inflammation related to the tick bite itself or a secondary infection by Strep bacteria can produce a similar, although usually not as large, area of redness. If treatment is not begun, other symptoms develop within days to weeks. These include facial paralysis, headaches, neck stiffness, heart palpitations and "migratory" joint pain which moves from joint to joint. Late manifestations of the disease includes arthritis, particularly affecting large joints, such as the knees, and neurological complaints including mental status changes, altered sensation, malaise, headache, and sleep disturbance.

Is there a test available to diagnose Lyme disease? The tests used in diagnosing Lyme disease are most accurate a few weeks after an infection develops. This is when the body has begun producing antibodies to fight the infection. Tests that have been developed to detect antibodies to Lyme disease include the enzyme-linked immunosorbent assay (ELISA) test and the Western blot test. A test called the polymerase chain reaction (PCR) may be used to diagnose chronic cases of Lyme disease.

How is Lyme disease treated? Most cases of Lyme disease can be cured with antibiotics, especially if treatment is begun early in the course of illness. Antibiotics that are effective for Lyme disease include doxycycline, amoxicillin, and cefuroxime (Ceftin).

Can Lyme disease be prevented? The best way of avoiding Lyme disease is by avoiding being bitten by infected ticks. A vaccine that was once used to prevent infections is no longer available. The CDC offers the following recommendations for protecting you from Lyme disease or other tick-borne illnesses:
  • Whenever possible, you should avoid entering areas that are likely to be infested with ticks, particularly in spring and summer when nymphal ticks feed.

  • If you are in an area with ticks, you should wear light-colored clothing so that ticks can be spotted more easily and removed before becoming attached.

  • If you are in an area with ticks, wear long-sleeved shirts, and tuck your pants into socks.

  • Application of insect repellents containing DEET (n,n-diethyl-m-toluamide) to clothes and exposed skin, and permethrin (which kills ticks on contact) to clothes, should also help reduce the risk of tick attachment. DEET can be used safely on children and adults but should be applied according to Environmental Protection Agency guidelines to reduce the possibility of toxicity.

  • Since transmission of B. burgdorferi from an infected tick is unlikely to occur before 36 hours of tick attachment, check for ticks daily and remove them promptly. Embedded ticks should be removed by using fine-tipped tweezers. Cleanse the area with an antiseptic
One of the most important reasons for early recognition and treatment of Lyme disease is that a percentage of those infected will have symptoms that last months to years. It appears that the sooner during the course of the disease that treatment is instituted, the less likely a persistent disease will occur. With measures to avoid tick bites and with recognition of early manifestations,most severe or chronic cases of Lyme disease can be avoided.