Excluding foods. The exclusion of entire categories of commonly eaten foods like whole grains and dairy requires frequent label reading in the supermarket and in restaurants. It may also increase the risk of deficiencies such as calcium, vitamin D, and B vitamins, if these nutrients are not consistently eaten from the allowed foods or a vitamin supplement. For example, there are some nondairy calcium-rich foods that are absorbed well by the body such as collard and turnip greens or canned bone-in sardines and salmon, but you would have to eat five or more servings of these greens and fish bones daily to meet recommended calcium needs. (Note that some greens like spinach that are touted to be calcium-rich also contain oxalates and phytates that bind to calcium so very little is actually absorbed.) One small, short-term intervention study of healthy participants showed a 53% decrease from baseline in calcium intake after following a Paleo diet for three weeks.  Furthermore, the exclusion of whole grains can result in reduced consumption of beneficial nutrients such as fiber and thus may increase one’s risk for diabetes and heart disease.
BOXROX – Competitive Fitness Magazine is the world's most widely reaching magazine for Crossfitters and fans of functional fitness. With 730.000 monthly readers from more than 180 countries it connects the worldwide fitness community. The magazine and its 200+ active contributors currently cover many topics including CrossFit®, weightlifting, nutrition, lifestyle and community related news. Everything that a fitness fan is searching for.
Nutrition & Physical Degeneration by Dr. Weston Price's book puts to rest a lot of myths about diet, dental, physical, and emotional health, and presents the strongest case for a super-nutritious Native (or Paleo) Diet. His book outlines the conditions/causes for exceptional health. A classic that was first published in 1938. The Soil and Health Library has a Book Review by Steve Solomon. If you don't buy the book at least read the review. N.B. If you live in one of the countries where this book is now in the public domain, you can read it online. But not if you live in a country where it is still under copyright protection.
CrossFit programming is decentralized, but its general methodology is used by thousands of private affiliated gyms, fire departments, law-enforcement agencies, and military organizations, including the Royal Danish Life Guards, as well as by some U.S. and Canadian high-school physical-education teachers, high-school and college sports teams, and the Miami Marlins.