Summer is just around the corner and so it's time to start to spending our weekends outside, gathering as much vitamin D as we can before fall makes its swift return. But what exactly is vitamin D and why is it such a vital component of human life? The Washington Post published an article Thursday morning examining how vitamin D relates to the sun and how our research of it is tied to puppies. Unfortunately, this isn't a story about playing with puppies in sun-soaked fields, but one of scientific research with discomforting ramifications.

Rickets, a disease that causes bones to soften, became especially prevalent as the industrial revolution sent child workers indoors and factory pollution began to blot out the sun. When a rash of urban children developed skeletal deformities, researchers stepped up to find the cause and figure out a solution.

In 1919, a scientist named Edward Mellanby successfully induced rickets in puppies by feeding them only bread and low-fat milk, noting that the resulting bone imaging and physical appearance of the dogs mimicked that of children suffering from rickets. Supplementing the diets of the wee puppers with yeast and orange juice (for B vitamins and scurvy-prevention, respectively) did nothing to stave off the bone disease; however, supplementation with both butterfat and cod liver oil did the trick. And with that, rickets was officially outed as a disease of deficiency. And where there's a deficiency, so, too, must there be a vitamin to be deficient in.

That's right, vitamin D. RIP puppies.

Head over to the Washington Post to read more.