Tag: Hormone function

According to the World Health Organization, vitamin A deficiency is the leading cause of preventable childhood blindness worldwide. This staggering statistic highlights the vital importance of the fat-soluble nutrient, which serves a unique dual function as both a visual pigment and a hormone.

While often overshadowed by carbohydrates, fat is a highly efficient and essential energy source for athletes; it provides 9 calories per gram, more than double that of carbohydrates or protein. This density highlights the critical role fats play in exercise, supporting energy, hormones, and overall performance.

Calcitonin, a hormone secreted by the thyroid gland's parafollicular cells, plays a key role in regulating mineral balance. Studies have shown that when blood calcium levels rise, calcitonin is released to help lower them, and in doing so, it also influences phosphorus levels.

According to the National Institutes of Health, a vitamin D–sufficient state allows the body to absorb between 30-40% of dietary calcium, a significant increase from the 10-15% absorbed when deficient. This remarkable effect highlights the critical role of vitamin D in regulating the body's ability to increase calcium absorption from the food we eat.

Though commonly labeled a vitamin, vitamin D is more accurately considered a steroid hormone due to its chemical structure and the way it acts within the body. Its classification as a vitamin was largely an 'historical accident' rooted in early research. This unique function explains its broad influence beyond just bone health, playing a crucial role in immune modulation and overall cellular function.