Could low cholesterol actually raise your stroke risk?

You’re likely well aware of the dangers of high cholesterol. Over time, elevated cholesterol — specifically LDL cholesterol, the kind many people refer to as “bad” cholesterol — causes your arteries to harden and narrow. Having high cholesterol can significantly increase your risk of heart disease and stroke.

For most adults, less than 200 mg/dl is considered a “healthy” cholesterol level, with LDL making up less than 100 mg/dl of that.

But new research suggests that having very low levels of LDL cholesterol can also pose a danger to your health.

A recent study published in the journal Neurology noted a correlation between participants’ LDL cholesterol levels and their risk of hemorrhagic stroke (the more rare type of stroke that occurs because of bleeding in the brain). For people whose LDL cholesterol levels were below 70, the risk of stroke was significantly higher. The authors of the study suggested that if having too high cholesterol and too low cholesterol can pose health risks, then perhaps moderation is the key — for people whose cholesterol levels fell between 70 and 99, stroke risk remained the same.

However, according to Cara East, MD, cardiologist and Director of the Soltero Cardiovascular Research Center at Baylor Scott & White Heart and Vascular Hospital – Dallas, having cholesterol levels that are “too low” should not be the primary concern. For most people, including 95 million U.S. adults aged 20 or older, high cholesterol is the real threat.

“While this study is intriguing, it does not address the complications of having a high LDL cholesterol, including heart attacks, regular strokes, and blockages in the leg or abdominal blood vessels,” she said. 

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Dr. East also noted that research on this correlation is far from conclusive.

“There are two studies in which patients were given a biologic cholesterol-lowering drug when they had an LDL cholesterol level just over 70 mg/dl,” she said. “In these studies, the patients’ LDL cholesterol could fall as low as 15 mg/dl. There were no demonstrated adverse consequences of having LDL cholesterol levels this low. In addition, there are people born with genetic variants that cause them to have lifelong low LDL cholesterol levels. One such disorder is PCSK9 deficiency, in which LDL cholesterol levels can be as low as 14 mg/dl, and they have no apparent problems with this.”

So, while this news is thought-provoking, more research is needed to truly determine the long-term effects of low cholesterol.

“This study is ‘hypothesis-generating’ but would need to be confirmed by looking for hemorrhagic strokes in other studies before we would recommend patients be concerned.”

Do you know your cholesterol numbers? Paying attention to your cholesterol is a critical part of maintaining your overall health. Many people are unaware that they have high cholesterol until they suffer a heart attack or stroke. Talk to your doctor about your personal risk factors and how you can maintain healthy cholesterol levels through diet and exercise.

Are you at risk for a stroke? Take this quiz tofind out.