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Fast Fact
One of the great wonders of the human body is the ability of damaged cells to be repaired or replaced. Red blood cells, for instance, live for about 120 days. Each day, about 1% of your red blood cells retire to be replaced by a fresh generation. The lens of the eye is a notable exception. The cells of the lens of the eye are never replaced; the proteins of the lens are never replenished. The lens cannot repair itself; damage accumulates over a lifetime.
Cataracts are the result of gradually accumulating damage to the proteins of the lens. The most important source of this damage is exposure to ultraviolet (UV) radiation, especially while one is young.
Behind the lens lies the retina, the thin lining of the back of the eye. The retina is the eye's miracle. This patch of tissue, about the size and thickness of a postage stamp, is able to dissolve and create a new image every tenth of a second.
Today in the United States, retinal diseases are the leading cause of blindness. Macular degeneration, the accumulation of damage in the retina, is the leading cause of blindness from retinal disease. Slowly, over the years, the macula is irreversibly damaged by exposure to UV radiation. About one third of adults over age 65 experience this steady decline of central vision, not correctable by glasses.
Excessive exposure to sunlight during early childhood is harmful to the eyes. Sunlight contains harmful UV radiation.
The risk for retinal damage from the sun's rays is greatest in children less than 10 years old, although the consequences usually do not become apparent until well after they are adults.
All children should be taught to wear sunglasses, especially between 10 AM and 2 PM, when ultraviolet exposure is the most dangerous. This is true even for children with darker eye colors, even though their darker pigments afford partial protection. Of course, children with light-colored eyes need sunglasses all the more.
Ultraviolet exposure is at its peak when children are at high altitudes, snow-covered landscapes, bright sandy beaches, or near reflective bodies of water.
All sunglasses are not the same. Effective sunglasses should block both UVA and UVB radiation. The sunglasses must be measured to block 99% to 100% of UVA or UV400 (400 nm is the wavelength of UVA radiation). Thankfully, all sunglasses block UVB radiation.
Large lenses that fit close to the eyes are best. Those that block visible blue light are even safer.
Expensive brand names and polarizing lenses are no guarantee.
Ordinary sunglasses make the situation WORSE! The dark lenses cause the pupils to dilate, allowing more of the dangerous UVA radiation to damage the lens and the retina.
My 13-month-old doesn't say any words. In fact, he seems to be doing less than he was four months ago and he is losing weight. The doctor told me to quit breastfeeding and come back in two months if I am still concerned. What do you think?
Dr. Greene: Several issues are raised in your question. Thirteen months is an average age for a Caucasian boy to start walking and anywhere between 9 and 15 months would not be surprising or concerning at all. As to learning to talk, we do get concerned if by 12 months kids don't babble or imitate sounds, but no words yet can be fine (especially if they are pointing to objects).
But kids who are losing weight, especially if they are also losing developmental milestones, should be checked right away to find out why. It could be from decreased nutrition or from a long list of other possibilities.
Personally, I would not stop breast milk as a way to assess or improve nutrition. A pediatric gastroenterologist is often the most skilled person in issues of feeding and growth.
Also, a developmental pediatrician could be helpful (this is a pediatrician with advanced training in child development). In California, we have a set of regional centers through the Department of Developmental Services where evaluations of children are paid for by the state if they are losing milestones under age 3. See if there is something comparable in your state.
Some studies suggest that taking thiamine (vitamin B1) 25mg to 50 mg three times per day is effective in reducing mosquito bites. This safe vitamin apparently produces a skin odor that is not detectable by humans, but is disagreeable to pregnant mosquitoes. Click here for more of Dr. Greene’s Tips For Avoiding Mosquito Bites.
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