It is the dead of winter and you are feeling run down. Need an excuse to take a weekend vacation? Find a place to visit so you can get at least 15 minutes of direct sunlight to your skin three times a week. Hopefully the ozone is ok where you choose to travel and you can go without sunscreen for just a short period of time to help you recharge. Sunlight and vitamin D increase serotonin, the mood neurotransmitter. It boosts your immunity, promotes healthy neuro-muscular functions, and helps protect you from some forms of cancer.