Being Ready for a Rainy Day: Vitamin D and Antioxidant Nutrients
Looking out the window, the day is gray. The sun is blocked by a heavy layer of clouds, it rays barely reaching the ground. In my case, it is overcast because of rainfall. In other places, smog may be the cause. Regardless, it is a poor day for cutaneous synthesis of vitamin D.
According to a systematic review of 195 studies in 44 countries published between 1990 and 2011 (Hilger et al, 2013), my situation is not unique. 88% of the studies had mean serum 25(OH)D levels below 75 nmol/L, 37% were below 50 nmol/L, and 6.7% were below 25 nmol/L. Vitamin D status was lower in institutionalized than community-dwelling older individuals.
Vitamin D is essential to maintain healthy bone and muscle function. Low serum 25(OH)D concentrations have been associated with other non-communicable diseases . Without adequate vitamin D levels, our health is at risk. Especially when faced with unusual challenges. Consider being in a severe car accident for example.
Blass and colleagues examined the effect of inadequate nutritional status on wound healing in adult trauma patients meeting strict criteria for persisting (10 days after trauma) problems for wounds to heal. Patients (n = 44) were classified by general nutritional status. Despite the fact that most patients were normal or overweight/obese, 15 patients (34%) were judged at risk for malnutrition and 9 (20%) were severely malnourished. Over half (60%) of the patients had inadequate serum 25(OH)D levels (< 50 nmol/L). Oxidative stress was higher in patients with delayed wound healing, measured by increased peroxides and reduced trolox equivalent antioxidant capacity (TEAC), than controls.
These two scientific papers demonstrate the importance of having adequate micronutrient status. They also show that increased oxidative burden, eg trauma to tissues, depletes the body. It is important to eat properly, exercise regularly, and get enough sleep. Nutrition is core to our survival. Nutrition is core to our health.
P.S. Remember that vitamin D3 (cholecalciferol) is more potent than vitamin D2 (ergocalciferol) in raising serum 25(OH)D levels.
Hilger J, Friedel A, Herr R, Roos F, Wahl DA, Pierroz DD, Weber P, Hoffmann K. A systematic review of vitamin D status in populations worldwide. 2013 Br J Nutr doi:10.1017/S0007114513001840
Blass SC, Goost H, Burger C, Tolba RH, Stoffel-Wagner B, Stehle P, Ellinger S. Extracellular micronutrient levels and pro-/antioxidant status in trauma patients with wound healing disorders: results of a cross-sectional study. 2013 Nutr J doi:10.1186/1475-2891-12-157