From Fossils to Football
One of the benefits of advances in modern medicine and an understanding of nutrition, has been the elimination of such diseases as Rickets in the children of industrialized countries.
A deficiency in calcium and Vitamin D, which can be a combined result of poor diet and lack of sunshine, often caused children in the past to develop a softening of the long bones in their legs, which would then bend outwards with the pressure from their growing bodies.
It was a problem that plagued society for centuries, until the role of Vitamin D was identified. Oddly enough, while it is thought that sunny countries would have fewer incidents of Rickets, many of those high temperature zones were also inhabited by people with dark skin, which was less likely to permit sunlight to penetrate into their bodies.
The industrial revolution of the 19th century, may have brought about the first childhood disease caused by environmental factors, when pollution from the factories obscured the sunlight in large cities. Medical specialists have theorized that the character of Tiny Tim in Charles Dickens' classic "A Christmas Carol", was a victim of Rickets.
The condition was and still is treatable, with improved diet, and measures taken to correct the misalignment of feet and legs.
One of the most famous Rickets victims, is O.J. Simpson, who came down with the disease at age two. His mother forced his legs to straighten and strengthen themselves, by putting his shoes on the wrong feet, and running a bar between them, so that his feet were made to face forward, instead of turning.