Advocates of the diet argue that the increase in diseases of affluence after the dawn of agriculture was caused by changes in diet, but others have countered that it may be that pre-agricultural hunter-gatherers did not suffer from the diseases of affluence because they did not live long enough to develop them. Based on the data from hunter-gatherer populations still in existence, it is estimated that at age 15, life expectancy was an additional 39 years, for a total expected age of 54 years. At age 45, it is estimated that average life expectancy was an additional 19 years, for a total expected age of 64 years. That is to say, in such societies, most deaths occurred in childhood or young adulthood; thus, the population of elderly – and the prevalence of diseases of affluence – was much reduced. Excessive food energy intake relative to energy expended, rather than the consumption of specific foods, is more likely to underlie the diseases of affluence. "The health concerns of the industrial world, where calorie-packed foods are readily available, stem not from deviations from a specific diet but from an imbalance between the energy humans consume and the energy humans spend."
The Paleo diet, also referred to as the caveman or Stone-Age diet, includes lean meats, fish, fruits, vegetables, nuts, and seeds. Proponents of the diet emphasize choosing low-glycemic fruits and vegetables. There is debate about several aspects of the Paleo diet: what foods actually existed at the time, the variation in diets depending on region (e.g., tropical vs. Arctic), how modern-day fruits and vegetables bear little resemblance to prehistoric wild versions, and disagreement among Paleo diet enthusiasts on what is included/excluded from the diet. Because of these differences, there is not one “true” Paleo diet.
Trying to devise an ideal diet by studying contemporary hunter-gatherers is difficult because of the great disparities that exist; for example, the animal-derived calorie percentage ranges from 25% for the Gwi people of southern Africa to 99% for the Alaskan Nunamiut. Descendants of populations with different diets have different genetic adaptations to those diets, such as the ability to digest sugars from starchy foods. Modern hunter-gatherers tend to exercise considerably more than modern office workers, protecting them from heart disease and diabetes, though highly processed modern foods also contribute to diabetes when those populations move into cities.
Paleo critics point out that not all grains are created equal—whole grains do not spike your blood sugar as much as refined grains. Even so, paleo dieters still steer clear of grains because they contain different compounds and proteins like gluten, lectins and phytates, which they claim cause inflammation in the body and block other nutrients from being absorbed. Paleo critics say these compounds are not a problem unless you have an allergy or sensitivity.
CrossFit headquarters' aggression can be enough to stunt interest in the WOD--almost. In April 2012, two avid CrossFitters, Jason and Shannon Janke, opened up the PR Cave, a sporting goods store in Yorba Linda, California, designed to cater to boxgoers all around Orange County. In November, they added a sign, "Where CrossFitters Shop," and had the slogan printed on mixer bottles for protein shakes. On January 16, they received a cease-and-desist from CrossFit, objecting to the use of CrossFitter. A month later, CrossFit filed suit.
He developed wacky routines: He had clients race their way through repetitions on a weight machine, and at one facility, he had them scramble up a 30-foot column in the middle of the room. Eventually, the owner of that gym welded disks to the pole to make him stop. "They added a hazard 15 feet up," Glassman cracked to clients, before signaling them to go up anyway. He got kicked out of that gym. He got kicked out of several gyms. "I've never wanted to be told what to do," Glassman says. "I think it's genetic."
Interestingly, all of these seemingly unrelated diseases share a common cause: damage to the intestinal lining which allows large, undigested food particles to make their way into the body. This is called “leaky gut and the autoimmune response”. Here is a 7-part video series by Prof. Loren Cordain describing the etiology of Multiple Sclerosis. And please watch this TED talk by Dr. Terry Wahls, MD as she describes how she reversed her Multiple Sclerosis with a paleo diet. If you have an autoimmune disease you might consider trying the autoimmune protocol of the paleo diet. If you do, please tell us about your experience.
CrossFit is promoted as both a physical exercise philosophy and a competitive fitness sport, incorporating elements from high-intensity interval training, Olympic weightlifting, plyometrics, powerlifting, gymnastics, girevoy sport, calisthenics, strongman, and other exercises. It is practiced by members of over 13,000 affiliated gyms, roughly half of which are located in the United States, and by individuals who complete daily workouts (otherwise known as "WODs" or "workouts of the day"). CrossFit has been criticized for allegedly causing people to suffer from unnecessary injuries and exertional rhabdomyolysis.