Effect of Vitamin D and Calcium Supplementation on Insulin Resistance

Abstract

As people spend more time indoors, Vitamin D deficiencies have increased drastically due to less sunlight exposure. New studies have linked Vitamin D deficiencies to calcium deficiencies since Vitamin D helps the human body absorb calcium properly. Calcium regulates insulin sensitivity, and calcium deficiencies reduce insulin sensitivity, indicating how Vitamin D deficiencies can lead to insulin resistance. I tested the individual and combined effects of calcium and Vitamin D supplementation on insulin resistance in Drosophila melanogaster, using physical activity to measure improvement in insulin resistance. There were 3 identical trials, and 5 vials in each trial. The control group was fed with only drosophila medium. The remaining vials had 3 grams of table sugar mixed with the medium. The second vial had no additions. The third vial had an addition of liquid calcium, and the fourth vial had Vitamin D instead. The last group had both supplements. After a week, the peristalsis contractions of each group’s larvae were counted in 30-second intervals. Additionally, adult flies from different groups were used for a climbing assay to measure the short-term impacts of these supplements on physical activity. Both measures yielded similar results: there was a visible increase in climbing performance and the number of peristalsis contractions in vials with supplementations compared to those without. The groups fed with individual supplements saw some increase, but the group with both supplements saw the most significant increase relative to sugar supplementation alone, supporting the hypothesis that calcium and Vitamin D supplementation improves insulin resistance.