Quit Smoking: Cigarette smoking interferes with the metabolism of vitamin D, resulting in poor muscle function.

Smokers have around 50 percent greater incidence of poor vitamin D levels compared with non-smokers. Vitamin D plays an important role in calcium absorption and bone health. It is synthesized in the skin through exposure to sunlight (about 15 minutes of sunlight each day). Food sources of vitamin D include egg yolks, saltwater fish, and liver.