When the 30 days are up, you can continue eating this way or gradually add some of the foods back in one by one to see which may have been causing your issues. Many people who become devotees of the lifestyle stick to a Paleo diet afterward (The Paleo diet is interpreted differently by different people, but in general, it’s a less strict, long-term lifestyle version of the Whole30).
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.”