The Butter Swap That Could Add Years to Your Life

I came across a new study in JAMA Internal Medicine, and I have to say—it really made me think. Researchers found that something as simple as swapping out butter for plant-based oils could significantly lower the risk of premature death and cancer. Just a 10-gram switch—about the amount you’d spread on a slice of toast—was linked to a 17% reduction in overall mortality and a 17% reduction in cancer-related deaths.

That’s a big impact for such a small change. And it got me thinking—not just about heart health, but brain health, too.

What the Study Says

This research reinforces the idea that not all fats are created equal. Butter is high in saturated fat, which raises low-density lipoprotein (LDL), commonly known as "bad" cholesterol. High LDL is linked to an increased risk of heart disease, a leading cause of death worldwide.

Plant-based oils, on the other hand, are rich in unsaturated fats, including monounsaturated and polyunsaturated fats, which have been shown to lower LDL cholesterol and reduce inflammation. Some plant oils also contain omega-3 fatty acids, which play a particularly important role in cardiovascular health and may even reduce cancer risk.

The Healthiest Sources of Fats

Experts emphasize that choosing fats in their most natural and unprocessed forms is key to maximizing health benefits. Some of the best sources of healthy fats include:

🥑 Olive oil – High in polyphenols and monounsaturated fats, known for reducing oxidative stress and supporting heart health.

🌰 Nuts and seeds – Almonds, walnuts, flaxseeds, chia seeds, and hemp seeds provide omega-3s, fiber, and plant-based protein.

🥑 Avocados – A rich source of monounsaturated fats, potassium, and fiber that supports heart health and insulin sensitivity.

🐟 Fatty fish – Wild salmon, sardines, and mackerel provide essential long-chain omega-3s (EPA and DHA), which reduce inflammation and support brain health.

🥥 Coconut and MCT oil – Contain medium-chain triglycerides (MCTs), which are rapidly converted into energy rather than stored as fat.

🧈 Grass-fed butter and ghee – Provide fat-soluble vitamins (A, D, E, and K2) and butyrate, which supports gut health.

What About Grass-Fed Butter?

While regular butter is high in saturated fat and linked to higher LDL cholesterol, grass-fed butter has a slightly different nutritional profile. It contains higher levels of omega-3s, conjugated linoleic acid (CLA), and vitamin K2, which may support heart health, immune function, and metabolic balance. It also contains butyrate, a short-chain fatty acid that promotes gut health and reduces inflammation.

However, even grass-fed butter should be consumed in moderation as part of a balanced diet. At the end of the day, the overall pattern of fat intake—favoring plant-based oils and omega-3-rich sources—matters most when it comes to reducing mortality and chronic disease risk.

What This Research Misses: The Brain Health Connection

Reading this study, I couldn’t help but wonder—why wasn’t brain health a bigger focus? The research highlights heart disease and cancer, but if fat intake has such a huge impact on longevity, wouldn’t it also play a major role in how well our brains function as we age?

The brain is about 60% fat, and the types of fat we consume directly affect its structure and function. It’s not just about energy—our brains need specific fats to build cell membranes, regulate inflammation, and facilitate communication between neurons.

One of the most essential components of brain health is omega-3 fatty acids, particularly DHA (docosahexaenoic acid) and EPA (eicosapentaenoic acid). These crucial fats—found in fatty fish, walnuts, flaxseeds, and certain plant oils—have been linked to:

🧠 Better memory

⚡ Faster thinking

🛡️ Reduced risk of neurodegenerative diseases like Alzheimer’s

At the same time, saturated fats, like those found in butter, have been associated with increased inflammation and beta-amyloid plaque buildup, which is a hallmark of Alzheimer’s disease. If plant-based oils are reducing mortality, it’s highly likely they’re helping preserve brain function as well.

The Best Fats for Brain Health

If we take the study’s findings and apply them to brain health, the message is clear:

💡 Choosing the right fats matters—not just for longevity, but for mental sharpness, memory, and cognitive resilience.

Some of the best sources of brain-boosting fats include:

🌿 Extra virgin olive oil – Rich in polyphenols and monounsaturated fats that reduce inflammation and protect brain cells.

🐟 Fatty fish (salmon, sardines, mackerel) – Packed with DHA and EPA, critical for maintaining brain function and preventing cognitive decline.

🌰 Nuts and seeds (walnuts, flaxseeds, chia seeds) – Provide plant-based omega-3s, which support neural health and reduce oxidative stress.

🥑 Avocados – A great source of monounsaturated fats, which promote healthy blood flow to the brain.

Final Thoughts

This research is a big step in reinforcing the health benefits of plant-based oils over butter, but it also serves as a reminder that what’s good for the heart is almost always good for the brain.

If reducing saturated fat intake can lower the risk of premature death and cancer, it’s highly likely that it’s contributing to better long-term cognitive health as well.

And honestly, if I’m making choices about my long-term health, I don’t just want to live longer—I want to stay sharp, focused, and able to enjoy life to the fullest.

That’s why I’ll be sticking with olive oil, fatty fish, and omega-3-rich foods as much as possible. What changes will you make to your diet?

The Study

Zhang, Y., Wang, D., Chiuve, S. E., et al. (2025). Butter and Plant-Based Oils Intake and Mortality. JAMA Internal Medicine.

Other Evidence

Mozaffarian, D. et al. (2010). "Effects of dietary fats on cognitive function in older adults." Archives of Neurology.

Martínez-Lapiscina, E. H., et al. (2013). "Mediterranean diet improves cognition: The PREDIMED-NAVARRA randomized trial." Journal of Neurology, Neurosurgery & Psychiatry.

Visioli, F., & Poli, A. (2019). "Fatty acids and cognition: A review of human studies." Advances in Nutrition.

Barberger-Gateau, P., et al. (2007). "Fish, meat, and risk of dementia: cohort study." BMJ.