A strict paleo diet does not allow dairy products because hunter-gatherers did not milk cows. Some paleo dieters say dairy is OK, especially if it is grass-fed because grass-fed butter, for example, has more omega-3s. Fermented dairy products are also OK for some paleo eaters because they have a lower content of lactose and casein, the two concerns paleo dieters have with dairy.

A study published in the Journal of Strength and Conditioning Research entitled "Crossfit-based high intensity power training improves maximal aerobic fitness and body composition" followed 54 participants for 10 weeks of CrossFit training. The study said that "...a notable percentage of our subjects (16%) did not complete the training program and return for follow-up testing." The authors said "This may call into question the risk-benefit ratio for such extreme training programs..."[62] In 2014, CrossFit, Inc. filed a lawsuit against the National Strength and Conditioning Association for publishing this study, alleging that the data were false and were "intended to scare participants away from CrossFit."[63] The NSCA denies CrossFit, Inc.'s allegations[63] but has issued an erratum acknowledging that the injury data were incorrect.[64] In September 2016, the District Court ruled in favor of CrossFit Inc.'s claims that the injury data were found to be false, but not that the NSCA was commercially motivated or that the publishing of the study was defamatory as the NSCA no longer stood behind the study.[65] In February 2017, CrossFit filed for sanctions against the NSCA after one of the NSCA's witnesses admitted to falsifying statements during deposition.[66] In May 2017, the Court issued 17 issues sanctions against the NSCA, writing that the organization did have a commercial motive to falsify the data, had published the false data knowingly to disparage CrossFit, and had misled the public with their erratum.[66] CrossFit was awarded $74,000 in legal fees and allowed to continue investigating the NSCA. If the neutral-party analysis of the NSCA servers turns up any further misconduct, CrossFit may file an amended complaint for further sanctioning and compensation for lost revenue.[67]
The WHO trial (so named because the international team of principal investigators contained World Health Organization members) tested the potential of clofibrate, a “pre-statin” cholesterol-lowering agent, to reduce heart attack morbidity and mortality. The investigators ultimately concluded that clofibrate "cannot be recommended as a lipid-lowering drug for community-wide primary prevention of ischaemic heart disease.” Nevertheless, clofibrate remained in use until 2002, when it was pulled for increasing cancer rates. In their review of studies such as the WHO trial, Uffe Ravnskov and David Diamond observe, “Despite the largely disappointing findings from 50 years of cholesterol lower[ing] trials, the indictment and conviction of cholesterol as the causal agent in CVD [cardiovascular disease] has stood the test of time. … [Yet] the grand effort to reduce cholesterol as a strategy to improve health has failed.”
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