Citrus associated with a 10% reduction in odds of developing breast cancer. Oranges were historically used for their high content of vitamin C, which prevents scurvy. Scurvy is caused by vitamin C deficiency, and can be prevented by having 10 milligrams of vitamin C a day. An early sign of scurvy is fatigue. If ignored, later symptoms are bleeding and bruising easily. British sailors were given a ration of citrus fruits on long voyages to prevent the onset of scurvy, hence the British nickname of Limey. Pectin is a structural heteropolysaccharide contained in the primary cell walls of plants. Limes and
Vitamin D deficiency ng/mL (375 nmol/L) are usually found, although in some cases 25(OH)D levels may appear to be normal. Periodic measurement of serum calcium in individuals receiving large doses of vitamin D is recommended. The official recommendation from the United States Preventive Services Task Force is that for persons that do not fall within an at-risk population and are asymptomatic, there is not enough evidence to prove that there is any benefit in screening for vitamin D deficiency. In the United States and Canada as of 2016, the amount of vitamin D recommended is 400 IU per day for children, 600 IU