Brief Answer:
eye power

Detailed Answer:
My Dear,
Thanks for sending your query to us.
As you are 48 i presume you have a presbyopic correction,that means you have been given glasses for reading and your distance vision is ok.
Factors which help in your case are
1) taking good care of your general health.Eat well ,exercise and yoga with emphasis on eye movement exercises including tratak.
2) use glasses when needed.If you use them all the time,your natura body capabilities are substituted and are never regained.
3) reading power increases every 2 years.These measures if not capable of reducing your power may prevent or slow down further progression
please do get back to me in case of further query in this regard

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