Exploring the evolving scientific and historical debates surrounding the dietary causes of coronary heart disease (CHD) and the impact of measurement errors in health research. Historical analyses reveal that the sugar industry strategically funded research in the 1960s to downplay the risks of sucrose while casting saturated fats as the primary dietary culprit. Contemporary experts now argue that long-standing government limits on saturated fats are scientifically unjustified, suggesting that health outcomes should be evaluated within the context of whole foods rather than isolated nutrients. Additionally, researchers emphasize that insulin resistance is more accurately predicted by specific lipid ratios, such as the triglyceride-to-HDL balance, than by total cholesterol alone. To address inaccuracies in these complex fields, the SIMFEX method is introduced as a robust statistical tool for correcting data contamination in epidemiological studies. Underscoring the necessity of objective data analysis and the critical re-evaluation of nutritional guidelines that may have been influenced by industry bias or flawed statistical modeling.