The journey to find the secret ingredient to eternal youth seems like an endless endeavor as people spend indefinite amounts of money on pills, face creams, and cosmetic procedures. For 91-year-old Mark Ambrose, who currently resides in the south of Spain, he credits his good health and youthful appearance to a cost-free ingredient that his own body produces — urine.

Ambrose, who drinks one cup of urine during a normal day, stumbled upon the golden elixir of youth on the Internet as he searched for a cure to back pain. Despite undergoing three spinal surgery operations in the U.K. and Spain, the 91-year-old still has a severely damaged back. Spinal specialists have told Ambrose that trying different painkillers for his chronic back pain is the only solution available at this time.

Urine therapy treatment was an idea that intrigued the man who had thought he was running out of options. "With nothing to lose, I thought I'd try the therapy to help to obtain a better quality of life for my remaining years,” Ambrose told the Daily Mail. His quest to tackle his back pain resulted in an extensive search of urine therapy to find out when or how much urine he should drink to soak up the benefits of the home-brewed elixir.

According to All-Natural, a natural healing resource center, urine therapy is viewed as a way to aid or sustain a person’s health. Treatment methods include drinking, injecting, massaging with, and bathing in urine. The golden liquid is highly sterile, consisting of 95 percent water, 2.5 percent urea, and 2.5 percent a non-toxic mixture of minerals, salts, hormones, and enzymes.

Curious about the body’s own “super-nutrition therapy,” Ambrose decided to take a small sample in a glass, carefully tasting the “clear, amber-colored liquid." To build up his drinking tolerance for the liquid, the 91-year-old kept taste-testing until he finally drank some a few days later.

Ambrose has even devised his own strategy to determine when the urine is potent enough to drink. “I learnt that one should note the color of one’s water and drink it if it’s mid-stream and a definite straw-color,” he said to the Daily Mail.

While light yellow or clear urine is often an indicator that a person is very well-hydrated, Ambrose believes it will not be as effective. “If it's clear then it's practically tasteless — and I think pretty useless as a healing agent,” he said. Conversely, if the urine is too yellow, then it is loaded with endless potential benefits, but it could also be too strong to drink.

To get rid of the foul aftertaste of the golden elixir, Ambrose confessed to the Daily Mail that he has a grape or two afterward, or simply does a quick rinse with water.

After doing urine therapy for three consecutive years, the 91-year-old man thanks his healthy physique and youthful appearance to urine. He admits that it could take weeks or even months for the unique beauty treatment to completely heal skin-related problems. Ambrose’s back pain still persists, but he affirms that the therapy has helped reduce the spinal column nerve pains to an acceptable level.

“I think I look and feel about ten years younger than my age. I possess a Spanish driving license up to 2014, I do all the cooking, I belong to a bridge club which I helped to start 20 years ago; and I’m learning to play the piano whenever I can because I never had the chance when I was younger,” Ambrose said.

One person who is not on board with Ambrose's urine therapy is his 87-year-old partner Joyce. She simply finds it impossible to get over her disgust of the very thought of consuming her own urine. “She has resisted all my attempts to persuade her to try the urine therapy,” said Ambrose.

There is still a lack of scientific evidence to support the health benefits of urine therapy to date. However, Ambrose is not the only one who has experienced some back pain relief using the alternative technique.

Sri Krishna Murthy, 39, started his urine therapy treatments in July 2010 after he was diagnosed with a severe back problem. Murthy experienced pain in the stomach, hands, legs, back, and other portions of his body, and suffered from multiple organ failure. After just three months of urine therapy, however, Murthy’s health improved day by day as his joints became more loose and mobile. He could also lift his hands easily and walk by himself with the support of walking stick, according to www.urinetherapy.in.

Dr. Rob Hicks, a general practitioner, believes drinking urine is counterproductive. “The kidneys are an efficient filtering system getting rid of what the body doesn't need,” he says, so consuming urine defeats the purpose of the kidney’s system.

To learn more about urine therapy and other alternative beauty treatments, click here.