Consuming butter in limited quantities may not increase the risk of heart disease or stroke – and it might actually be slightly protective against diabetes, a new study has claimed.
Researchers from Tufts University in the US found that butter consumption was only weakly associated with total mortality, not associated with cardiovascular disease, and slightly inversely associated with diabetes.
Based on a systematic review and search of multiple online academic and medical databases, researchers identified nine eligible research studies including 15 country-specific cohorts representing 636,151 unique individuals with a total of 6.5 million person-years of follow-up.
Over the total follow-up period, the combined group of studies included 28,271 deaths, 9,783 cases of cardiovascular disease, and 23,954 cases of new-onset type 2 diabetes.
Researchers combined the nine studies into a meta-analysis of relative risk.
Butter consumption was standardised across all nine studies to 14 grammes per day, which corresponds to roughly one tablespoon, researchers said.
Overall, the average butter consumption across the nine studies ranged from roughly one-third of a serving per day to 3.2 servings per day, they said.
The study found mostly small or insignificant associations of each daily serving of butter with total mortality, cardiovascular disease, and diabetes.
“Even though people who eat more butter generally have worse diets and lifestyles, it seemed to be pretty neutral overall,” said Laura Pimpin, previously from Tufts and currently with UK health forum.
“This suggests that butter may be a “middle-of-the-road” food: a more healthful choice than sugar or starch, such as the white bread or potato on which butter is commonly spread and which have been linked to higher risk of diabetes and cardiovascular disease,” said Pimpin.
According to her, butter is a worse choice than many margarines and cooking oils – those rich in healthy fats such as soybean, canola, flaxseed, and extra virgin olive oils – which would likely lower risk compared with either butter or refined grains, starches, and sugars.
“Overall, our results suggest that butter should neither be demonised nor considered “back” as a route to good health,” added Dariush Mozaffarian from Tufts University.
The findings were published in the journal PLOS ONE.