There is more and more evidence out there that suggests an important connection between our hearts and brains. Most recently, research published in the American Heart Association's journal Circulation found that certain fluctuating levels of "bad" cholesterol could harm cognitive performance.
The study included 4,428 adults aged 70 to 82 years old from Scotland, Ireland and the Netherlands. Participants either had preexisting vascular disease or were at a higher risk for the condition based on their medical history or lifestyle choices, such as smoking, hypertension or diabetes, according to a news release.
To test the effect of "bad" cholesterol, comprised of low-density lipoproteins, on brain health, researchers administered a test to study participants that required them to name a color written out in a different colored ink that the word spelled (for instance the word "red" was written in blue ink). The adults in the study with the highest LDL cholesterol variability took around 2.7 seconds longer to identify colors than those with lower variability.
"While this may seem like a small effect, it is significant at a population level," Roelof Smit, lead study author and a Ph.D. student at Leiden University Medical Center in Leiden, the Netherlands.
Though the study used European participants, the researchers say that the results have application in American lifestyles as well, as they often put individuals at a higher risk of hypertension and other cardiovascular complications.
This isn't the first instance of cholesterol playing a role in brain health. A 2014 study published in JAMA Neurology found that unhealthy fluctuations of both "good" and "bad" cholesterol could contribute to the onset of Alzheimer's.
To that end, Smit called the results of his recent study "an important puzzle piece" connecting cardiovascular and brain health. He also added that more studies are required to uncover how these findings could eventually impact clinical practice.