If my math is right, in 14 years he will be an infant.
For the record: I think this article is mostly describing a honey trap for scamming rich celebrities in the future, but I don't expect this kind of anti-ageing to be a linear process. It's probably a lot easier to "gain back" 5 years of your life by radically changing your lifestyle and eating habits, but much, much harder to rewind the clock by 10 or 15 years.
I don’t believe it is. I’ve been on a similar regimen minus the metformin for some time and the supplements he takes and the formula followed is fairly well researched with dozens of bio hackers across the world doing similar. The metformin alone is known to reverse aging significantly. Even myself just taking Nicotinamide Ryboside I have noticed a massive difference in everything from skin complexion to eye site to energy levels and improved cognition.
I wonder what happens after that? Does he cease to exist as a human?