|
|
Astigmatism is the most common vision problem. It may accompany nearsightedness or farsightedness. It is usually caused by an irregularly shaped cornea, but sometimes it is the result of an irregularly shaped lens. Either type can be corrected by eyeglasses, contact lenses, or refractive surgery.
The most common childhood diseases include croup, chickenpox, ear infections, flu, pneumonia, ringworm, respiratory syncytial virus, scabies, head lice, and asthma.
The average human gut is home to perhaps 500 to 1,000 different species of bacteria.
Limit intake of red meat and dairy products made with whole milk. Choose skim milk, low-fat or fat-free dairy products. Limit fried food. Use healthy oils when cooking.
The horizontal fraction bar was introduced by the Arabs.