Hey everyone, Lorin here with your new insights into Fitness for the Modern Man. Today I want to talk to you about Vitamin D. We have been seeing Vitamin D in the press a lot lately and in a recent report the FDA has increased the Recommended Daily Allowance (RDA) from 200 IU (International Unit) to 600 IU, a significant increase of 300%! You are in great shape if you get 10 minutes of sunlight a day and eat oily fish like Salmon which yields approximately 900 IU per serving, but not so good if you are a ‘modern man’ stuck in the office all day. It is also to be noted that smelly foods like Salmon sometimes get left in the office refrigerator and this does not make friends.
The maximum daily allowance (MDA) of vitamin D is in the 4000 IU range and even higher if you are pregnant, so it is fairly difficult to overdose on Vitamin D. Just to give you a quick perspective, this quantity is the equivalent of eating 230 eggs! 
Our modern man lifestyle of home to car to office to car to home does not provide to much natural opportunity for Vitamin D. Maybe on the weekends we get out for a few minutes and feel the sunlight on our face, but most of the time it is untouched up by our work life habits. It is no coincidence that most of the northern hemisphere above 42 degrees shows deficiencies of Vitamin D in 75% of the population.
Vitamin D is created when UV-B rays from the sun react with D3 in the skin thus causing a chemical reaction in our bodies that manufactures this nutrient. UV-B rays do not penetrate through glass, only UV-A which do not provide the health benefits our bodies need, so unfortunately car rides don’t count towards the sunlight needed for vitamin conversion. Depending on the time of year the skin will need various times exposed to sunlight. In Summer time we need 10 minutes, 20 minutes in Spring and Autumn, and 30 minutes in the Winter. It is already hard enough for most of us to get outside and the additional required minutes in the winter makes it no surprise that everything from depression to illness increases in these months. 
There are many options to help with this like a sun lamp, an inexpensive and easily purchased product that will provide UV-B rays and can be plugged into a standard wall outlet.
http://www.amazon.com/Zoo-Med-Basking-Reptile-Fluorescent/dp/B00361HC9C
The best defence against deficiency is a combination of Vitamin D supplements and food. Food is really the best medicine that we have. So during these long dark winter months be sure to eat plenty of oily fish like Salmon, leafy greens, veggies and proteins like spinach, mushrooms, broccoli, and eggs. 
All this talk of food is making me hungry! Omelets anyone?
Until next time be well, be healthy!
Very interesting. Never thought of a sun lamp–good idea!