BRAIN FOOD: Can Lowering Cholesterol Help Protect Your Brain?

We often hear about cholesterol in the context of heart health. But a new study suggests it may also play a significant role in brain health—and that lowering LDL cholesterol (“bad cholesterol”) could reduce your risk of developing dementia.

Like many things in health, the key appears to be balance. Not too high… but not too low either. Here’s what the research found—and what it could mean for protecting your memory and cognitive function.

What the Study Looked At

The study, published in BMJ Journal of Neurology, Neurosurgery & Psychiatry, tracked the cholesterol levels of adults over time and looked at how those levels correlated with their risk of dementia—including Alzheimer’s disease.

It focused specifically on LDL cholesterol, the kind most often associated with artery-clogging plaque and increased stroke and heart attack risk.

Here’s what they found:

• People with LDL levels below 70 mg/dL had a:

  • 26% lower risk of all-cause dementia

  • 28% lower risk of Alzheimer’s-related dementia

• People with LDL levels between 55–70 mg/dL still had reduced risk, but slightly less so (18% lower)

• People with very low LDL (below 30 mg/dL) did not see any further benefit

  
  

  This suggests there may be a “sweet spot” for LDL—low enough to reduce vascular risk, but not so low that it loses its protective effect.

  
  

What About Statins?

The protective effect was even stronger in people who were taking statins—cholesterol-lowering medications often prescribed to manage cardiovascular risk.

This supports earlier research suggesting that managing LDL cholesterol may help reduce not only stroke risk but also cognitive decline, likely by improving blood flow to the brain and reducing inflammation.

Why Cholesterol Affects the Brain

It might seem surprising that something in the bloodstream can affect memory or mood—but cholesterol and the brain are closely linked.

Here’s how high LDL cholesterol may increase dementia risk:

• It contributes to plaque buildup in arteries, including the tiny blood vessels that supply the brain

• It can increase the risk of microstrokes and chronic low-level inflammation

• Over time, poor circulation affects brain oxygenation, function, and resilience

But here’s the nuance: cholesterol also plays a role in building brain cells and maintaining cell membranes. Too little may not be helpful either, which is why the study’s findings are so important.

There’s a threshold. Lowering LDL to moderate levels helps. Going extremely low may not add extra benefit.

So, What Can You Do?

If you’re managing your cholesterol or have been advised to start, here are a few takeaways:

• Talk to your doctor about your target LDL level. The research points to below 70 mg/dL as beneficial for brain and heart health

• If you’re taking statins, you may be getting brain-protective benefits as well as cardiovascular ones

• If your LDL is above 130 mg/dL, it might be time to explore options—whether through medication, diet, or lifestyle

• Focus on foods that support vascular and cognitive health: leafy greens, nuts, olive oil, legumes, oily fish, and foods rich in fibre

Final Thoughts

We’ve known for a while that what protects the heart tends to protect the brain. This study adds another layer to that idea—suggesting that managing cholesterol, particularly LDL, could meaningfully reduce your dementia risk.

The sweet spot? Keep it low, but not extreme.

For most people, that means working with your doctor to aim for LDL below 70—a range that seems to offer brain benefits without tipping into unnecessary risk.

It’s one more tool in the brain health toolkit. And when the stakes are this high, every tool counts.

Evidence

1. Kim J, et al. (2025). Association of LDL-C levels and statin use with dementia risk: A population-based cohort study. BMJ Journal of Neurology, Neurosurgery & Psychiatry, April 2025.

2. Reitz C, et al. (2010). Plasma lipid levels in the elderly and risk of Alzheimer’s disease. Archives of Neurology, 67(6), 718–726.

3. Anstey KJ, et al. (2017). Risk factors for dementia: An updated systematic review. Alzheimer’s & Dementia, 13(3), 292–298.

4. MacSweeney E. (2025). Commentary on LDL-C threshold effects and cognitive outcomes. Quoted in Medical News Today, April 2025.