On the 3rd, the New York Post reported that "parents are feeding their children butter to help them sleep" on the social media platform TikTok. Indeed, videos of parents feeding their babies spoonfuls of butter have been posted on TikTok and Instagram. A female influencer with over 1 million followers claimed she lost 30 pounds (14 kg) by only eating butter, eggs, and meat. She also noted that her acne and psoriasis disappeared.
Butter is gaining popularity. The per capita consumption in the U.S. is expected to reach its highest level in 60 years in 2024. Once criticized for being unhealthy, claims have emerged that it may actually be beneficial for health. But does eating butter really cure diseases and help with weight loss? Is it safe for parents to feed butter to their babies to help them sleep? Experts have sharply criticized this notion. They noted that excessive consumption of butter could raise the risk of death by up to 15%.
◇More than 220,000 medical professionals tracked for over 30 years
A research team led by Professor Dong Daniel Wang from Harvard University announced on the 6th in the Journal of the American Medical Association (JAMA) Internal Medicine that they had tracked 221,054 nurses over 33 years and found that overconsumption of butter significantly increased mortality risk while switching to plant-based oils reduced it.
The research team conducted surveys every four years on how often the nurses consumed specific types of food, alongside analyzing medical information. The results showed that those in the highest consumption group, eating 1.5 times the size of a tablespoon of butter daily, had a 15% higher mortality risk than those who consumed the least. Parents feeding butter to put their babies to sleep were, in effect, jeopardizing their children's futures.
Conversely, those who consumed the most plant-based oils, such as olive oil, showed a 16% lower mortality risk compared to those who consumed the least. Professor Wang stated that "a simple dietary change of switching from butter to soybean oil or olive oil could yield significant long-term health benefits," adding that "from a public health perspective, this means that a substantial portion of deaths from cancer and other chronic diseases could be prevented."
◇Replacing with olive oil may reduce cancer deaths
Butter has been known to be harmful to health due to its saturated fat content. Fats are structures made up of carbon atoms linked together like chains. Saturated fat is formed when all carbon atoms are bonded with two hydrogen atoms, while unsaturated fat occurs when some carbon atoms are only bonded with one hydrogen atom. Saturated fats are abundant in animal fats, while unsaturated fats are found in oily fish and plant-based oils.
Saturated fats can raise cholesterol levels, which are fat molecules that can lead to cardiovascular disease. This is because they impair the receptor function in the liver that expels cholesterol. In contrast, unsaturated fats activate this receptor, thereby lowering cholesterol levels. Research has shown that substituting butter with plant-based oils can lower cholesterol levels.
This study did not indicate that butter increases the risk of death from cardiovascular disease. Instead, it was associated with deaths caused by cancer. The Harvard research team stated that replacing 10 grams of butter daily with the same amount of plant-based oil could reduce the risk of death from cancer by as much as 17%.
◇Evidence to refute fake news on social media
Experts evaluated that this study presented evidence to refute fake news circulating on social media. Professor Thomas Sanders, a chair in nutrition at King's College London, said to the Science Media Center, "The conclusion of this study is that choosing unsaturated plant-based oils is healthier than butter," adding that "especially in a situation where unfounded claims about the harmfulness of plant-based oils have shaped negative public opinion on social media, the results of this study are even more meaningful." The Science Media Center is an organization that conveys expert opinions to the media regarding scientific research related to social issues.
Professor Sarah Berry from the same university stated, "There are numerous influencers on social media promoting butter as a health food and claiming that plant-based oils are fatal." She continued, "However, while excessive butter consumption increases the risk of cancer and overall mortality, plant-based oils have been shown to lower the mortality risk from cardiovascular diseases and cancer." She advised, "Even if it tastes good, butter should be consumed sparingly."
However, Professor Georgy Davey Smith from the University of Bristol pointed out the limitations of the study. He said, "People who consume a lot of butter tend to have twice as many smokers compared to those who avoid it," indicating that other factors might influence mortality rates rather than just food consumption.
References
JAMA Internal Medicine (2025), DOI: https://doi.org/10.1001/jamainternmed.2025.0205