The UV damage from tanning beds has been well documented for decades, but what's novel here is the genetic methylation analysis showing accelerated aging at the DNA level.
What's wild to me is the economics. Tanning salons charge $30-50/month to give you skin cancer. Meanwhile vitamin D supplements cost $10/year and achieve the same health benefit people claim to seek from tanning.
The only rational argument I've heard for controlled UV exposure is building a base tan before vacation to prevent burning. But even then, 1-2 minutes in a low-wattage bed would suffice - not the 20+ minute sessions people actually do.
Where are you seeing vitamin D supplements for $10/year? That’s several orders of magnitude less than most OTC supplements.
A Google search for vitamin d results in ads, ahem "sponsored results", for 180 servings for $27, which is about $55 for a full year assuming it's one serving per day, which is the same decimal order of magnitude as $10 (but, I suppose, since we are on HN, is three or four orders of magnitude in binary)