K E Fuller | PubMed Health

PubMed2001

Vitamin D: balancing cutaneous and systemic considerations.

BACKGROUND: Vitamin D insufficiency may lead to various health problems. By encouraging sun protection to prevent skin cancer, physicians may be limiting a major source of vitamin D for many individuals. METHODS: We did a literature review on issues related to vitamin D inadequacy, particularly those relevant to various racial/ethnic groups. RESULTS: Vitamin D is an important hormone with many physiologic roles beyond those related to bones, including blood pressure regulation and acting as a tumor suppressant. The recommended amount of vitamin D has recently increased for adults over age 50. Moreover, some researchers are urging higher doses for the entire population to prevent osteoporotic fractures. CONCLUSIONS: Previous studies that have found serum levels of vitamin D in their sun-protected subjects to be in the normal range may need to be reevaluated. In concert with counseling sun protection, physicians should consider discussing vitamin D intake, typically in the form of supplements.

Adult↗

PubMed2000

Low birth-weight infants: the continuing ethnic disparity and the interaction of biology and environment.

African-American infants weigh on average 200-300 grams less at birth than do European-American infants, leading to a two-fold higher rate of low birth-weight (LBW) infants. This birth weight disparity has not changed significantly over the past 95 years. Numerous research studies have been undertaken to elucidate this disparity. While various factors have been found to be associated with increased risk for having a LBW infant, including maternal anthropometrics, health and age, prenatal care, and socioeconomic status, none have been found to entirely and adequately explain the continued birth-weight differential. Researchers have concluded that there is something different in the environment and/or genetics of African-American women compared to European-American women, but are at a loss to clearly define the factor other than to say it must relate to the racism suffered by African-American women leading to more stress during pregnancy. While racism is probably an additional factor, one genetic/environmental variable, which has been overlooked, is the interaction of heavy pigmentation with degree of latitude. Heavy pigmentation blocks ultraviolet B (UVB) radiation. At high latitudes, such as in the US region, inadequate exposure to UVB radiation prevents the conversion of the prohormone to the hormonal form of vitamin D. The resulting low levels of serum vitamin D in the pregnant woman disrupt calcium homeostasis leading to intrauterine growth retardation, premature labor, and hypertension: all risk factors for LBW infants.

Black or African American↗