A cheap drug widely used for type 2 diabetes turns out to have anti-aging properties that can potentially allow humans to increase their lifespan by about 50 percent and live up to 120 years old. Earlier this year, researchers from Belgium tested the effect of metformin, a drug commonly prescribed for type 2 diabetes patients, on the roundworm C. elegansThey found out that it caused the worms to age slower and stay healthy for a longer time, adding about 40 percent to their average lifespan.

When mice were treated with the drug, they even developed stronger bones, The Telegraph reported.

Last year, a study done by researchers from Cardiff University and published in the journal Diabetes, Obesity and Metabolism showed that metformin does not only help people fight the disease, but allows them to live longer as well.

"Patients treated with metformin had a small but statistically significant improvement in survival compared with the cohort of non-diabetics, whereas those treated with sulphonylureas had a consistently reduced survival compared with non-diabetic patients," the researchers reported in a 2014 press release.

Now, the U.S. Food and Drug Administration has given the green light for researchers to proceed with a clinical trial, which will begin next year. The trial will involve 3,000 participants aged 70 to 80 years old from various U.S. locations. The trial is expected to run for five to seven years.

Professor Gordon Lithgow from the Buck Institute for Research on Ageing, one of the advisers for the trial, said that metformin could cause the progression of different diseases in the body to slow down.

"If you target an ageing process and you slow down ageing then you slow down all the diseases and pathology of aging as well. That's revolutionary. That's never happened before," he told The Telegraph.

FDA Director Dr. Robert Temple agreed that many age-related problems, such as dementia, eyesight loss, muscle tone loss and others could be addressed if the trial is successful.

"That would be something never done before. If you really are doing something to alter aging the population of interest is everybody. It surely would be revolutionary if they can bring it off," Temple said.

American Federation for Aging Research executive director Stephanie Lederman, who is also one of the advisers in the clinical trial, clarified that the study is not about "looking for a fountain of youth." She said they want to avoid that perspective and instead show that "what we're trying to do is increase health span, not look for eternal life," according to The Telegraph.

The clinical trial, called Targeting Ageing with Metformin (TAME) will begin next winter.