The Cholesterol Paradox: Does “Bad” Cholesterol Protect the Very Old?

Challenging Conventional Wisdom with New Evidence from Sardinia’s Blue Zone

In February 2025, a fascinating study published in the journal Nutrients turned heads in the medical community. Researchers from Sardinia—one of the world’s renowned “Blue Zones” where people routinely live to 100 or beyond—examined 168 nonagenarians (people aged 90+). What they found challenges decades of advice about cholesterol: those with higher LDL cholesterol (the so-called “bad” cholesterol) lived significantly longer than those with lower levels.

Specifically, nonagenarians with LDL-C ≥130 mg/dL had an average survival time of 3.82 years over the six-year follow-up, compared to just 2.79 years for those below 130 mg/dL—a roughly 37% longer lifespan. Even after adjusting for factors like sex, comorbidities, and self-rated health, the group with moderately elevated LDL-C had a 40% lower risk of death.

This isn’t an isolated finding. It’s part of what’s known as the cholesterol paradox in the elderly: observational studies repeatedly show that higher cholesterol levels in older adults are linked to lower all-cause mortality, flipping the script on what we see in younger people.

The Roots of the Paradox

Back in 2016, a systematic review in BMJ Open analyzed data from over 68,000 elderly people across multiple cohorts. The conclusion? High LDL-C was inversely associated with mortality in most participants over 60. In fact, those with higher LDL-C often lived as long as—or longer than—those with low levels. This pattern has been replicated in numerous studies since, including large cohorts in China and the U.S.

Why might this happen?

• Biological roles of cholesterol: LDL isn’t just “bad”—it’s essential for cell membrane repair, hormone production, vitamin D synthesis, and immune function. As we age, the body faces more inflammation, infections, and cellular damage. Higher cholesterol could support immunity and repair, acting protectively.
• Reverse causality critique: Critics argue low cholesterol isn’t protective but a marker of frailty—illness, malnutrition, or wasting diseases (like cancer or chronic conditions) lower cholesterol levels naturally. The Sardinian study countered this by excluding severely ill participants and those with poor health ratings, yet the paradox persisted.
• No clear harm from high LDL in the very old: In extreme longevity hotspots like Sardinia, moderate hypercholesterolemia didn’t prevent reaching 90+; it correlated with surviving longer after that.

But What About Heart Disease and Statins?

Here’s where nuance matters. While all-cause mortality (death from any cause) often favors higher cholesterol in observational data, cardiovascular events can still rise with very high LDL—even in the elderly.

Randomized trials of statins (cholesterol-lowering drugs) show benefits across ages:

• A 2019 Lancet meta-analysis of 28 trials found statins reduce major vascular events proportionally regardless of age, including over 75 (though absolute benefits are smaller in primary prevention).
• Guidelines (e.g., 2018 AHA/ACC, updated ESC/EAS 2025) recommend considering statins for primary prevention in those >75 if LDL is 70–189 mg/dL and no life-limiting illness—via shared decision-making.
• For secondary prevention (existing heart disease), benefits are clearer even in the very old.

Current guidelines as of 2025–2026 emphasize individualized care:

• ESC/EAS 2025 update: Reaffirms aggressive LDL targets for high-risk patients, no upper age cutoff.
• U.S. guidelines: Reasonable to start moderate-intensity statins >75 for primary prevention if elevated LDL and good life expectancy.
• No blanket “lower is always better” for nonagenarians—focus on quality of life, frailty, and polypharmacy risks.

The Bottom Line: One Size Doesn’t Fit All

The Sardinian study and cholesterol paradox highlight that aging changes the rules. What harms a 50-year-old (high LDL accelerating atherosclerosis) might not harm—or could even help—a 90-year-old facing infections, frailty, or other threats.

This doesn’t mean ignoring cholesterol entirely. Heart disease remains a top killer, and lowering LDL prevents events in many. But for the very elderly, blindly pushing LDL as low as possible could overlook benefits.

Always consult your doctor. Decisions on statins or lifestyle changes should weigh your overall health, risks, and goals—not just a single blood test number.

As research evolves (with ongoing trials like STAREE and PREVENTABLE focusing on older adults), we’ll get clearer answers. For now, the paradox reminds us: longevity isn’t about chasing youth-like labs—it’s about thriving at every age.

Sources: Errigo et al. (2025) in Nutrients; Ravnskov et al. (2016) in BMJ Open; Cholesterol Treatment Trialists’ Collaboration (2019) in The Lancet; various 2025 guideline updates.