High protein foods can be converted into muscle in elderly adults too, a study shows, proving that those protein shakes won't just benefit the young folks at the gym. Therefore, as adults age and begin to lose important muscle mass, a diet high in lean proteins will be beneficial, as well as some gentle exercises. But currently, it's estimated that 27% of older adults aren't getting adequate amounts of protein in their diet.

On an interesting note, this study was partially funded by the National Cattlemen's Beef Association, but I'm recommending that seniors get their protein from lean sources like fish, chicken breasts, lean turkey, nuts and low-fat dairy.