Is going commando bad for your balls ?

Brief-less: Scots "go commando" under their kilts all the time. Men may find it somewhat "liberating" to skip wearing underwear. However, if you engaging in sports which would cause a lot of jostling- wearing briefs may be helpful or if sports are contact - using a cup would afford protection.

Agree with Dr. F: Not wearing underwear or wearing loose fitting underwear is okay. Have a healthy diet, exercise 30 minutes/day, drink plenty of water, have safe sex, no tobacco alcohol weed or street drugs. For nutrition: http://www.choosemyplate.gov/. Get HPV vaccine. Wish you good health!