Ask unlimited questions for free
Increased intake of vitamin D has been shown to reduce fractures up to 25% in older people.
The familiar sounds of your heart are made by the heart's valves as they open and close.
Oliver Wendell Holmes is credited with introducing the words "anesthesia" and "anesthetic" into the English language in 1846.
Asthma cases in Americans are about 75% higher today than they were in 1980.
Most women experience menopause in their 50s. However, in 1994, an Italian woman gave birth to a baby boy when she was 61 years old.
For a complete list of videos, visit our video library