A Single Oral Vitamin D₃ Bolus Reduces Inflammatory Markers in Healthy Saudi Males

Vitamin D deficiency has increased in the general population and is a public health issue. Vitamin D plays an important role in regulating the immune system, e.g., by modulating the production of inflammatory cytokines. In most countries, the recommended maximal daily dose of vitamin D₃ is 4000 IU (100 µg) per day. In this study, we investigated whether a single vitamin D₃ bolus can reduce the levels of the inflammatory markers interleukin (IL) 6, IL8 and tumor necrosis factor (TNF) within one month. Fifty healthy Saudi males were recruited from the local community in Jeddah city and were orally supplemented with a single dose of 80,000 IU vitamin D₃. Serum samples were collected at time points 0, 1 and 30 days, and serum levels of IL6, IL8 and TNF, parathyroid hormone (PTH), 25-hydroxyvitamin D₃ (25(OH)D₃), triglycerides, cholesterol, calcium (Ca²⁺) and phosphate (PO_4-) were determined. On average, the vitamin D₃ bolus resulted in a significant increase in vitamin D status as well as in a significant decrease in the levels of inflammatory cytokines even one month after supplementation without changing serum Ca²⁺, PO_4- or lipid levels. In conclusion, single high-dose vitamin D₃ supplementation is safe for reducing inflammation markers and may lead to an update of current recommendations for vitamin D intake, in order to prevent critical health problems.