Updated on March 2, 2022.
Like an intricate road system, your blood vessels carry blood and its cargo of oxygen and nutrients all over the body. And, just as the surface of a roadway affects how easily vehicles can travel on it, the lining of those blood vessels is crucial to your health.
Your blood vessels’ interior lining, a thin membrane called endothelium, is made of endothelial cells. These cells have a number of jobs, including helping your vessels relax or contract moment by moment, as well as influencing your immune system and your blood’s ability to clot. Keeping endothelial cells healthy can help ward off heart disease and more.
One way to do that? Eat your oatmeal, or another fiber-rich hot or cold breakfast cereal. A study suggests that eating plenty of fiber at breakfast is kinder to the lining of your blood vessels than a high-glycemic-index breakfast like cornflakes.
The hidden hazards of a high-glycemic breakfast
In a 2009 study published in Journal of the American College of Cardiology, researchers evaluated how different foods affected the health and function of the endothelium in a group of people who were either overweight or obese, but otherwise healthy. The results suggested that glycemic index matters.
What is glycemic index? Simply put, it’s a way to measure how easily your body breaks down carbohydrates in a particular food into a sugar called glucose that your body uses for energy—and how fast that food causes your blood sugar to rise. White bread has a high glycemic index, for example, while bran cereal has a low one.
In the study, volunteers were assigned to eat a breakfast of either cornflakes (which are low in fiber), a high-fiber cereal, a supplement containing glucose, or just water. When researchers measured the participants' endothelial cells’ function, they found impairment in people who had eaten the cornflakes or glucose. Specifically, the blood vessels did not relax as they should.
That’s not good. Like cracks in a roadway that eventually become potholes, an impaired endothelium may lead to blood-vessel damage. That damage is clearly observable in people with diabetes. It can pave the way for hardened arteries and heart disease.
Spiking your sugars has consequences
The relationship between high-glycemic-index foods and blood vessel health is becoming clearer to scientists. These sugar-spiking foods are like heavy trucks that overload a roadway. They increase levels of damaging and inflammatory molecules and sticky compounds, which cause immediate changes in endothelial cells. Over time, this can create wear and tear in blood vessels.
So do yourself a favor. Pass up the cornflakes and white bread and start your day instead with a wholesome, high-fiber, whole-grain breakfast. Your blood vessels will thank you for it.
