I think it's a bunch of bullsh*t. All who have taken science in school would have remembered that the function of urine is to remove soluble waste and toxins from our bodies. So essentially, you are just recycling your toxins when you drink urine.
Heard it's popular in Taiwan too. Remembered reading an article about it quite some time ago. Some doctors were interviewed regarding the claims made by the urine-drinker. But all the doctors were skeptical about the benefits stated.