Butter Lovers and Seed Oil Haters Are Both Wrong, New Research Confirms

March 21, 2025

Butter has been a dietary staple for thousands of years. Historians believe humans have been making this animal fat-based spread since the Neolithic period, also known as the New Stone Age. Today, butter consumption is higher than ever—research shows that between 2000 and 2022, butter consumption in the US increased by 45 percent. But while butter is one of our oldest foods, consuming it in excess may have negative health effects.

A new study from Harvard T.H. Chan School of Public Health has suggested that swapping butter for plant-based oils, including many of the heavily demonized-on-social-media seed oils, like canola and soybean, could reduce the risk of death by 16 percent. High butter consumption, however, was linked with a 15 percent higher risk of mortality.

The findings directly contradict the strong narrative around fats that has emerged on social media in the last few years and heightened considerably in the last few months.

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A quick search for “butter” and “health” on TikTok brings up several videos from influencers, with thousands of views, pedaling the message that animal fat is a “superfood” and we should all be eating more of it. A similar search for seed oils brings up plenty of content encouraging users to stay away due to their alleged inflammatory effect on the body. You can read more on the theories behind seed oil conspiracies here.

But the science says differently. Research suggests that, while butter does contain some nutrients, it is also high in saturated fat, which increases levels of LDL cholesterol in the body. High LDL cholesterol is a known risk factor for cardiovascular disease—the leading cause of death in the US and around the world.

“For some reason that is not clear to me, a myth has been floating around the internet that butter is a healthy fat, but there is no good evidence to support this,” Walter Willett, MD, professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health, told CNN.

Plant-based oils, on the other hand, are much higher in unsaturated fats like omega 3 and omega 6, which are associated with heart health. Of all the oils studied, the researchers found that olive, canola, and soybean came out the best.

“We need both omega-6 and omega-3 fatty acids; soybean and canola oil have both,” Willett said. “Corn and sunflower oil have very little omega-3 fatty content; these can be part of a mix of different oils, but should not be relied upon as a sole source of plant oil.”

The health benefits of plant-based oils

According to the new study, swapping just 10 grams of butter with a plant-based oil was linked with a 17 percent reduced risk of total mortality and cancer-related deaths.

“Seventeen percent is quite a big change, especially when you look at the public health perspective. Imagine how many deaths we can reduce in the general population,” said study co-author Yu Zhang, PhD.

He added: “We are not suggesting that people should avoid butter entirely, but we are recommending that even a small reduction in butter in replacement for plant-based oils in a daily diet could lead to very substantial, long-term health benefits.”

Willet also explained that while beef tallow wasn’t included in the study, which was conducted using 33 years’ worth of data from more than 220,000 people, the researchers expected that it would have a similar impact to butter on health. Like butter, beef tallow has risen in popularity on social media recently, assisted by growing interest in carnivore diets.

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In general, carnivore diets have been linked with a high risk of kidney stones, gout, and osteoporosis. “In a strict carnivore diet whereby no plant foods are allowed, the body is stripped of any opportunity to have phytonutrients that protect us from cancer and many chronic diseases,” Angel Luk, RD recently explained to VegNews. “These phytonutrients are exclusively found in plants.” Raw carnivore diets, which involve eating uncooked meats, are also rising in popularity, and these also present a risk of parasites, foodborne illness, and nutritional deficiencies.

The new Harvard Health study supports a growing body of research that associates plant-based oils with better health outcomes. In 2023, for example, one study presented at the American Society for Nutrition’s annual Nutrition meeting suggested that consuming just half a tablespoon of olive oil every day could reduce a person’s dementia risk by 28 percent.

“Our study reinforces dietary guidelines recommending vegetable oils such as olive oil and suggests that these recommendations not only support heart health but potentially brain health as well,” lead researcher Anne-Julie Tessier, RD, PhD said in a statement at the time. Olive oil has also been linked with a reduced risk of stroke and heart disease, and improved digestive health, too.