Gosh yes, my son was born with a milk sensitivity and that was my intro into how much sneaky stuff goes into our food! It was maddening to me that I could not even eat most breads or canned goods because somehow they had milk in them (I was nursing)!
And you might be on to something with the sunlight there. I'm from Ohio and it's cloudy half the time, lots of rainy days and diluted rays. I'll have to look up Jack Kruse, I've certainly been noticing that people from countries where walking and sitting outdoors is the norm are far healthier!