Vitamin D and Weight Change: A Mendelian Randomization, Prospective Study.

Area of Science:

• Endocrinology
• Nutritional Science
• Human Genetics

Background:

• Vitamin D status is crucial for numerous physiological processes.
• Understanding the relationship between vitamin D and weight management is important for public health.
• Genetic predisposition may influence vitamin D levels and metabolic outcomes.

Purpose of the Study:

• To investigate the association between genetically determined 25-hydroxyvitamin D levels and long-term weight change.
• To assess the impact of genetic variations related to vitamin D on body mass index and weight fluctuations over time.

Main Methods:

• A population-based, prospective study in Lausanne, Switzerland, utilizing data from three follow-ups (2009–2021).
• Construction of a weighted genetic risk score (GRS) based on 115 single nucleotide polymorphisms (SNPs) associated with vitamin D levels.
• Analysis of weight changes over 5, 10, and 15 years in relation to GRS and 25-hydroxyvitamin D levels using Spearman correlation and regression analyses.

Main Results:

• The GRS positively correlated with baseline 25-hydroxyvitamin D levels (0.198) and body mass index (0.036).
• No significant association was observed between GRS quartiles and weight changes at 5, 10, or 15 years (p = 0.401 for 5-year change).
• A statistically significant but clinically negligible association was found between GRS-derived vitamin D and weight change at 5- and 15-year follow-ups.

Conclusions:

• Genetically determined 25-hydroxyvitamin D levels show minimal association with long-term weight gain.
• The findings suggest that genetic factors influencing vitamin D status have a limited role in predicting weight changes.
• Further research may explore other environmental or lifestyle factors influencing the vitamin D-weight relationship.