The Paleo diet includes nutrient-dense whole fresh foods and encourages participants to steer away from highly processed foods containing added salt, sugar, and unhealthy fats. However, the omission of whole grains, dairy, and legumes could lead to suboptimal intake of important nutrients. The restrictive nature of the diet may also make it difficult for people to adhere to such a diet in the long run.  More high-quality studies including randomized controlled trials with follow-up of greater than one year that compare the Paleo diet with other weight-reducing diets are needed to show a direct health benefit of the Paleo diet. Strong recommendations for the Paleo diet for weight loss cannot be made at this time.

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,[27][28][29][30] as well as by some U.S. and Canadian high-school physical-education teachers, high-school and college sports teams, and the Miami Marlins.[14][31][32]
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. [8] 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.
This 2003 CrossFit Journal article captures an early conception of a universal, multi-event test of fitness that laid the foundation for CrossFit competition, including what would become the CrossFit Open and the CrossFit Games. The design requirements for such a test "included but were not limited to the following: quantifiable results; consistency with the CrossFit fitness concept; raising our commitment to improving absolute strength, relative strength, and gymnastic foundations; balancing intrinsic abilities of smaller and larger athletes; emphasizing exercises critical to and foundational to advanced training; mixing training demands within each test and, of course, over the total competition; a design that would identify an athlete’s weaknesses and possibly stand as a workout plan for improving overall fitness; and, finally, we wanted to design a competition that would be 'hard as hell.'"
×