I've read a lot about nutrition from an alternative viewpoint in the past couple years - a viewpoint that questions the high cholesterol/heart disease hypothesis.

Below is an AI response on this issue. The best book on it is "The Great Cholesterol Con" by Malcolm Kendrick.

Key Evidence Questioning a Strong Correlation Critics of the "lipid hypothesis" (the idea that high cholesterol directly causes heart disease) point to several lines of evidence from observational studies, reanalyses of major trials, and meta-analyses. Here's a summary of prominent examples:

Weak or Inverse Associations in Large Cohort Studies:

The Framingham Heart Study (ongoing since 1948, involving over 5,000 participants) is often cited as foundational for linking cholesterol to heart disease. However, reanalyses show that total cholesterol levels were only weakly predictive of heart attacks in some groups. For instance, a 1992 follow-up found that for people over 50, higher cholesterol was not associated with increased mortality and sometimes correlated with longer life. In fact, falling cholesterol levels over time were linked to higher death rates from heart disease. A 2016 systematic review in the British Medical Journal (BMJ) analyzed data from 68,000 elderly participants across 19 studies and found no association between high LDL cholesterol and all-cause mortality. Surprisingly, high LDL was inversely associated with mortality in some cases, suggesting it might be protective in older adults. Critiques of Seminal Studies Supporting the Link:

Ancel Keys' Seven Countries Study (1950s–1970s) popularized the cholesterol-heart disease connection by showing correlations in selected countries. However, critics like Uffe Ravnskov (author of "The Cholesterol Myths") have pointed out selection bias: Keys excluded data from 15 other countries where high-fat diets (and thus higher cholesterol) did not correlate with more heart disease. A 2017 reanalysis in the Journal of Clinical Epidemiology confirmed that including all data weakens the correlation significantly. The Honolulu Heart Program (a long-term study of over 8,000 Japanese-American men) found in 2001 that low cholesterol levels were associated with higher mortality rates, including from heart disease, challenging the idea that lower is always better. Statin Trials and Intervention Studies:

Statins (cholesterol-lowering drugs) reduce heart attack risk in high-risk groups, but some analyses suggest the benefits may not be primarily due to cholesterol reduction. A 2015 meta-analysis in the Expert Review of Clinical Pharmacology reviewed 11 statin trials and found that the mortality benefits were similar regardless of how much cholesterol was lowered, implying other mechanisms (e.g., anti-inflammatory effects) might be at play. This questions whether cholesterol itself is the key driver. The 4S Trial (Scandinavian Simvastatin Survival Study, 1994) showed benefits from simvastatin, but a 2005 re-examination in the BMJ noted that the absolute risk reduction was small (about 3%), and benefits were not clearly tied to baseline cholesterol levels. Population-Level and Paradoxical Observations:

In certain populations, high cholesterol coincides with low heart disease rates (e.g., the "French Paradox," where high-fat diets in France lead to high cholesterol but low heart attack rates, possibly due to other dietary factors like antioxidants). A 2018 study in the Journal of the American Geriatrics Society of over 1,200 centenarians found that high total cholesterol was common and not linked to shorter lifespans, suggesting it's not a strong risk factor in advanced age. Meta-analyses, such as one in 2010 from the American Journal of Clinical Nutrition reviewing 21 studies (over 347,000 participants), found no significant association between saturated fat intake (which raises cholesterol) and heart disease risk, indirectly questioning cholesterol's role. Confounding Factors and Alternative Explanations:

Many studies highlight that inflammation, oxidative stress, insulin resistance, and lifestyle factors (e.g., smoking, obesity) are stronger predictors of heart attacks than cholesterol alone. For example, a 2009 review in Current Opinion in Lipidology argued that small, dense LDL particles (not total levels) might be more relevant, and high cholesterol could be a symptom of underlying issues rather than the cause. Autopsy studies, like a 1960s analysis of heart attack victims, showed that many had normal cholesterol levels, while some with high cholesterol had clear arteries.