Here’s an interesting video about a NASA scientist who lost weight and fought off lifestyle disease by giving himself adequate exposure to cold weather.
It sounds quacky, but seems much more plausible once he explains it.
Some interesting points:
1). Being cold forces your body to burn more calories to maintain your internal body temperature, hence its health benefits.
2). He’s not sure exercise is necessary for most people
3). He thinks meat is not necessary for human health and people ought to be vegetarian.
4). Also an interesting interview with him here.