Butter intake and risk of death in US adults
What it found
People who ate the most butter had a 15% higher chance of dying over 33 years compared to those who ate the least.
Swapping 10 grams of butter a day for plant oils was linked to a 17% lower chance of dying.
What they found
Studies in people
Butter and overall death
People who ate the most butter had a 15% higher chance of dying from any cause than those who ate the least. This was seen across 221 054 adults followed for up to 33 years.
Butter and cancer deaths
Eating more butter was linked to a higher chance of dying from cancer. For every extra 10 grams eaten per day, the chance of a cancer death rose by 12%.
How butter was used
Butter spread on bread or food was linked to a small rise in the chance of dying. Butter used for baking and frying showed no clear link to death rates.
Plant oils instead of butter
Swapping 10 grams of butter a day for the same amount of plant oils like olive, soybean, or canola oil was linked to a 17% lower chance of dying overall. It was also linked to a 17% lower chance of dying from cancer.
Other findings
Measuring butter intake
The researchers counted butter added at the table and butter used in cooking. They asked participants about their diets every 4 years to track changes over time.
What the authors conclude
- They found that eating more butter was linked to a higher chance of dying, while eating more plant-based oils was linked to a lower chance.
- They suggest that replacing butter with plant oils like olive, soybean, or canola oil may help prevent early deaths.
How it was done
Earlier studies gave mixed results about whether eating butter is linked to dying sooner. The authors wanted to use long-term diet records to see how butter and plant oils relate to deaths from all causes, cancer, and heart disease.
They followed 221 054 US women and men for up to 33 years using three large health studies. Participants filled out food questionnaires every 4 years to report how much butter and plant oil they used. A doctor checked medical records to confirm the cause of 50 932 deaths.
What it can’t tell you
- This study followed people over time, so it can only show a link between butter and death, not prove that butter caused it.
- People reported their own diets, so the amounts of butter and oil they remembered might not be exact.
- The participants were mostly nurses and health workers in the US, so the findings might not match other groups.
Who paid
- Funding
- Funded by NIDDK NIH HHS; NIA NIH HHS; NINR NIH HHS (from the PubMed record).
- Conflicts
- Conflict of Interest Disclosures: Dr Guasch-Ferré reported grants from the Novo Nordisk Foundation and the International Nut and Dried Fruit Council outside the submitted work. Dr Willett reported grants from the National Institutes of Health during the conduct of the study. Dr Stampfer reported grants from the National Institutes of Health during the conduct of the study. No other disclosures were reported.
- Authors work at
- Harvard T.H. Chan School of Public Health, Massachusetts; Brigham and Women's Hospital and Harvard Medical School, Massachusetts; Broad Institute of MIT and Harvard, Massachusetts
The paper
- Title
- Butter and Plant-Based Oils Intake and Mortality
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Zhang Y, Chadaideh KS, Li Y, et al (2025). Butter and Plant-Based Oils Intake and Mortality. JAMA internal medicine. doi:10.1001/jamainternmed.2025.0205Free full textPubMed 40048719DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error