Body & HealthFact

After 40 your arms seem to get too short.

Over the years the eye's lens loses elasticity and hardens, and the ciliary muscle weakens too. Focusing power for near vision drops from about 7 to 10 dioptres in youth to roughly 0.5 dioptres by 50. Most people notice from 40 onwards, and it keeps progressing until around 65.

Useful: Presbyopia is not a disease but a material property of the lens.

Source: en.wikipedia.org

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