CRP and Heart Disease Risk: A Functional Beverage Opportunity?

The identification of low-density lipoprotein cholesterol (LDL) as a major modifiable risk factor for cardiovascular disease (CVD) has helped save countless lives over the past few decades. Yet, despite significant progress in the prevention and treatment of CVD, it remains the leading cause of death throughout the Western world and the second most-common cause of death worldwide. Equally troubling, nearly half of all CVD events occur in people without elevated blood cholesterol or lipid levels.

As a result, the last 10 years has found researchers searching for new and better predictors of CVD risk and following a trail of clues that has increased understanding of inflammation as an underlying contributing factor in the development of CVD. Once considered simply the body’s healing response to insults like bacterial infections, cuts and twisted ankles, inflammation is now recognized as playing a pivotal role in all phases of atherosclerosis.

C-reactive protein (CRP), a molecule released into the bloodstream during systemic inflammation, is an important marker of inflammation that many researchers believe offers a new way to assess CVD risk. The American Heart Association, Dallas, and Centers for Disease Control and Prevention, Atlanta, now recommend that CRP levels be used to further evaluate CVD risk in individuals whose Framingham risk score puts them at intermediate (10% to 20%) risk of heart disease or stroke. The Framingham risk score is a global risk assessment tool that weighs risk factors such as age, total and high-density lipoprotein (HDL) cholesterol levels, smoking, blood pressure and presence of diabetes to assess an individual’s risk of developing heart disease or stroke within their next 10 years of life.

The growing body of research supporting CRP’s CVD predictive value also raises an important question: Is CRP simply a marker of inflammation or is it a proatherogenic, or causative, culprit? Although initial reports suggested CRP levels merely reflected an underlying inflammatory process, accumulating evidence now suggests that CRP could also be a proatherogenic factor. CRP is present in atherosclerotic lesions, and some studies suggest it may actively contribute to the progression and/or instability of atherosclerotic plaque.

While CRP’s role in the development of CVD is far from conclusive, there is growing circumstantial evidence that reducing CRP levels might benefit some individuals. However, while the “scientific jury” is still out on whether lowering CRP levels reduces CVD risk, a simpler question presents itself. If CRP levels can be reduced relatively easily and safely, why not try to bring them down? For example, some strategies that reduce CVD risk, such as lowering LDL levels with statin drug therapy, also reduce CRP levels.

We have known for more than 30 years that plant sterols effectively reduce LDL cholesterol concentrations. More recently, The Coca-Cola Company, Atlanta, found that plant sterols in a nonfat matrix were also effective, which led to the development of Minute Maid® Premium Heart Wise™ orange juice as a fat-free alternative to traditional plant-sterol-fortified fats.

While testing the effectiveness of plant sterols in a reduced-calorie juice recently, we decided to evaluate whether plant sterols also impacted CRP concentrations. We found that, when consumed twice a day with meals for eight weeks, a reduced-calorie orange juice beverage with plant sterols (1 gram per 240 mL) not only reduced LDL cholesterol by 9.4%, it also cut CRP levels by 12%. An identical test using regular orange juice fortified with plant sterols yielded similarly significant results.

Dietary therapy is the cornerstone of strategies aimed at reducing LDL cholesterol to reduce the risk of CVD. Incorporating foods fortified with plant sterols into a low-fat diet, along with other lifestyle modifications such as exercise, have been recommended by the National Cholesterol Education Panel, part of the National Heart, Lung, and Blood Institute, Bethesda, MD. In light of our recent findings and the increasing evidence supporting a possible role of CRP in the etiology of atherosclerosis, the strategy of fortifying beverages like orange juice with plant sterols could offer consumers a delicious option with two heart-heath benefits: lowering both LDL cholesterol and CRP concentrations.

Carolyn Moore, Ph.D., R.D., is the Principal Scientist Liaison with the Texas Medical Center for The Beverage Institute for Health & Wellness at The Coca-Cola Company. Moore established the first Nutrition Advisory Board for The Minute Maid Company, and has overseen several clinical trials demonstrating new beverage product efficacy.