Among a group of 1,995 adults, researchers found that those with higher vitamin D serum levels also tended to have better cardiorespiratory fitness than participants with sub-optimal vitamin D readings. Researcher Dr. Amr Marawan adds, “Our study shows that higher levels of vitamin D are associated with better exercise capacity… We also know from previous research that vitamin D has positive effects on the heart and bones. Make sure your vitamin D levels are normal to high. You can do this with diet, supplements, and a sensible amount of sun exposure.” European Journal of Preventive Cardiology, October 2018