The vitamin most closely associated with sunshine is imperative to your overall health; vitamin D maintains strong bones and muscles, and can help treat and prevent diabetes, hypertension, glucose intolerance, and multiple sclerosis. Conversely, a deficiency in vitamin D can result in sleep issues or daytime sleepiness, compromised cardiovascular health, anxiety and depression, and even cancer.
Unless you live in the Caribbean or some other gorgeous vacation locale, you don't have the luxury of effort-free high doses of sunshine every day. And if you do, you're likely loading up on sunblock, which coincidentally is a bit of a vitamin D block as well. So how much of this vitamin do you need, and how can you get it without toasting your skin to a crisp?
The daily recommendation hovers around 400-800 IU, depending on age (and who you ask — Mayo Clinic and NIH both say 600). Conditions like eczema, cancer, heart disease and cystic fibrosis require a higher dosage, which typically calls for supplements like cod liver oil. If you're not into supplements, just make sure you're incorporating some of the following foods into your diet, and you're good to go.