Most people start to need reading glasses when they are over 40. Some people may need them at 45. Generally speaking, when people find difficult doing near work, like reading, sewing and threading a needle, they may need reading glasses to help them see better. The symptoms might be blurry vision when reading. Some people may get headaches and eye strain when doing close work.
My father started using reading glasses a few years ago (about 45). He could not see the small texts on newspaper . It is also impossible to thread a needle. And he often get frequent headaches, eyestrain or eye fatigue while reading.
In rare cases, people under 40 years may suffer from presbyopia though it is said that presbyopia often happens among people who is older than 40 years old. I suggest you to have your eyesight checked right now. If you often hold your books at an arm's distances to view them, you may need to buy a pair of reading glasses.
The people who have presbyopia often have reading problems. Besides, they also struggle with up-close tasks such as drawing. Sewing or playing board games. Some people also complain that they can't see the food on their plate. If you suffer from all the problems, you may need to have your eyesight checked. presbyopia often happens among people who are older than 40 years old. But in some rare cases, people who are younger than that age may suffer from this kind of vision problem too.