The sensible advice is generally to spend a few months gradually increasing your unprotected sun exposure, then towards the end of the summer may be able to hang out unprotected in the morning/midday sun for an hour or two without burning. Of course everyone's mileage is going to vary here, as is their tolerance for risk vs reward of sun exposure.
There is some evidence than sun exposure decreases your risk for many other cancers moreso than it increases your risk of skin cancer, although exposure patterns and other factors are going to be very important here. And obviously there's a lot more than just cancer that a healthy body and immune system is protecting you from.