Health Risks And Toxicological Outcomes Of Excessive Vitamin D Intake

Abstract

Background: Vitamin D plays a crucial role in bone metabolism, immune modulation, and overall health. Despite ample sunlight exposure, vitamin D deficiency is common in Saudi Arabia due to various factors affecting vitamin D levels (cultural dress code, sun exposure, lifestyle and dietary habits). Therefore, broad supplementation is common in the population. However, there have been an increasing number of cases of vitamin D toxicity related to high-dose and/or unsupervised supplementation practice, which, in some instances, have led to serious vitamin D toxicity health issues. 

Objective: The objective of this research is to synthesize current scientific literature pertaining to health risks and toxicological implications of excessive vitamin D consumption in regards to clinical, biochemical, and systemic effects.

Methods: This research utilized both a narrative and systematic review approach. For literature published between 2015 to 2025, databases consisted of PubMed, Scopus, etc. Data were then extracted and analyzed thematically across clinical, biochemical, and policy dimensions.

Conclusion: the increasing rates of supplements being over prescribed, as well as overdosing and toxicity on those who may truly not be deficient and their health could be at risk raises many questions around the slogans of ‘what is the sensible and balance approach and evidence of practice, within nutritional supplementation’. The need for dosing (not all, not only released), regulated doses, routine and regular checking, and educating the public are all critical to address and minimize the risk of “hypervitaminosis”.