Heat kills solid-state devices. The more you keep it cool, the longer the component will last. If you weren't mining, how long did you anticipate keeping/using your laptop for? If you wanted to use your laptop for 10 years, then you will likely kill your laptop faster with mining.

On the other hand, if you expected to use your laptop for 2 years, then there is a good chance that mining (without overclocking, and with good ventilation) will not affect your useable lifespan.

Don't expect mining at that rate to provide enough income to allow you to buy a new laptop 2 years from now though!