Google AdSense by default serve ads based on your visitor’s browsing history that Google stores in browser’s cookie. Depending on your website’s niche, disabling it can serve more targeted ads to your visitors and increase your AdSense earnings.

A niche with high competition in Google AdWords (where there are a lot advertisers bid for keywords in your site) would benefit from disabling the option, while site’s with less targeted keyword might suffer.

To disable 'Interest-based ads, go to Allow & block ads → Advanced settings from your Gooogle AdSense dashboard.

From there, disable the interest-based ads in the Interest-based Ads Preferences section.