There is a difference between chronological age and biological age. When calculating your biological age, they use parameters like how often you exercise, blood pressure, diet, stress management, and other markers. A more detailed way is to actually measure the length of the ends of your DNA, called telomeres. As we age, they shorten with each DNA replication.
Good news, though! Omega 3 fatty acids and chinese tea have been shown to actually preserve the telomere length, thereby slowing the aging process.
So, keep drinking your chinese tea - Black tea can be drank first thing in the morning on an empty stomach. Green and oolong teas are natural fat emulsifiers, so are best drank with meals.
Good sources of Omega 3s are ground flax seeds, walnuts, edamame, cold water fish, and of course Omega 3 - EPA/DHA supplements!