|
|
A cataract is a clouding of the eyes' natural lens. As we age, some clouding of the lens may occur. The first sign of a cataract is usually blurry vision. Although glasses and other visual aids may at first help a person with cataracts, surgery may become inevitable. Cataract surgery is very successful in restoring vision, and it is the most frequently performed surgery in the United States.
As the western states of America were settled, pioneers often had to drink rancid water from ponds and other sources. This often resulted in chronic diarrhea, causing many cases of dehydration and death that could have been avoided if clean water had been available.
More than one-third of adult Americans are obese. Diseases that kill the largest number of people annually, such as heart disease, cancer, diabetes, stroke, and hypertension, can be attributed to diet.
In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.
The shortest mature adult human of whom there is independent evidence was Gul Mohammed in India. In 1990, he was measured in New Delhi and stood 22.5 inches tall.
![Relationship between the number of CAG repeats in a gene and the age of onset of Huntington disease.](https://biology-forums.com/gallery/47/medium_234464_20_01_15_10_59_34_202501361.jpeg)
![Men and women report having fewer days with stressors as they go from middle to older adulthood, and ...](https://biology-forums.com/gallery/27/medium_660366_08_04_17_10_05_19_27557730.jpeg)