Dairy fats may not increase heart disease, stroke risk

Whole dairy products such as full-fat milk, cheese and butter may not increase a risk of early death from heart disease or stroke, say scientists.

The study, published in the American Journal of Clinical Nutrition, found no significant link between dairy fats and cause of death or heart disease and stroke.

In fact, certain types of dairy fat may help guard against having a severe stroke, researchers said.

"Our findings not only support, but also significantly strengthen, the growing body of evidence which suggests that dairy fat, contrary to popular belief, does not increase risk of heart disease or overall mortality in older adults," said Marcia Otto, assistant professor at University of Texas in the US.

"In addition to not contributing to death, the results suggest that one fatty acid present in dairy may lower risk of death from cardiovascular disease, particularly from stroke," said Otto.

The study showed how multiple biomarkers of fatty acid present in dairy fat related to heart disease and all-cause mortality over a 22-year period.

This measurement methodology, as opposed to the more commonly used self-reported consumption, gave greater and more objective insight into the impact of long-term exposure to these fatty acids, researchers said.

Nearly 3,000 adults age 65 years and older were included in the study, which measured plasma levels of three different fatty acids found in dairy products at the beginning in 1992 and again at six and 13 years later.

None of the fatty acid types were significantly associated with total mortality. In fact one type was linked to lower cardiovascular disease deaths.

People with higher fatty acid levels, suggesting higher consumption of whole-fat dairy products, had a 42 percent lower risk of dying from stroke.

The 2015-2020 Dietary Guidelines for Americans currently recommend serving fat-free or low-fat dairy, including milk, cheese, yogurt, and/or fortified soy beverages.

However, Otto pointed out that low-fat dairy foods such as low-fat yogurt and chocolate milk often include high amounts of added sugars, which may lead to poor cardiovascular and metabolic health.

"Consistent with previous findings, our results highlight the need to revisit current dietary guidance on whole fat dairy foods, which are rich sources of nutrients such as calcium and potassium," said Otto said.

"These are essential for health not only during childhood but throughout life, particularly also in later years when undernourishment and conditions like osteoporosis are more common," she said.