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An identified risk factor for osteoporosis is the intake of excessive amounts of vitamin A. Dietary intake of approximately double the recommended daily amount of vitamin A, by women, has been shown to reduce bone mineral density and increase the chances for hip fractures compared with women who consumed the recommended daily amount (or less) of vitamin A.
Most fungi that pathogenically affect humans live in soil. If a person is not healthy, has an open wound, or is immunocompromised, a fungal infection can be very aggressive.
Autoimmune diseases occur when the immune system destroys its own healthy tissues. When this occurs, white blood cells cannot distinguish between pathogens and normal cells.
Each year in the United States, there are approximately six million pregnancies. This means that at any one time, about 4% of women in the United States are pregnant.
More than 150,000 Americans killed by cardiovascular disease are younger than the age of 65 years.
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