I always wondered about this. Since I was very young, let's say after age 14 or so I rarely travelled for summer vacation and was living in Europe and had almos

I always wondered about this. Since I was very young, let's say after age 14 or so I rarely travelled for summer vacation and was living in Europe and had almost no vitamin D from sunlight (working as software engineer and being a nerd so all my hobbies were indoors). I have always felt like I missed having a good time at a beach while sun was shining (I remember it from family vacations when I was very young). Since then I have spent couple of months in a country near equator and gotten lots of (hours per day) sunlight. I feel healthier and happier now. I also used to have deficiency of vitamin B when I was very young. I remember I had to eat lots of fish oil to replenish my B complex (recommended by my doctor).