A recent research study provides evidence that apples improve cardiovascular health and reduce cholesterol.
A diet rich in plant-based foods such as fruits, vegetables, nuts, seeds, and whole grains is known to reduce the risk of cardiovascular disease, in particular, coronary artery disease and stroke. Apples are the second most-produced fruit in the United States with a production of 5.7 million metric tons in 2017. Quick, easy to eat, apples are readily available and known for their health benefits, but can apples improve cardiovascular health?
The American Journal of Clinical Nutrition recently published a new research study that specifically looked at whether apples improve cardiovascular health. The small study included forty adults, both men and women, who suffered from mild hypercholesterolemia (high cholesterol). Volunteers consumed two apples per day for eight weeks, then following a four-week ‘wash out’ period, where the apples were no longer consumed. After this period, the participants drank an apple control drink for a further eight weeks. The apple control drink was consumed so that researchers could compare the effects of eating the whole apple against drinking an apple beverage.
A green variety of apple called ‘Renetta Canada’, which is rich in proanthocyanidins, was selected for the study. Proanthocyanidins are known to be very powerful antioxidants that protect cells from harmful free radicals. This type of antioxidant has been found to be twenty times higher than those found in vitamin C. Throughout the study, urine and blood samples were analysed as well as body fat composition, height, weight, waist circumference, blood pressure, and more complex cardiovascular measurements. Volunteers were asked to keep a strict diet diary throughout the study period.
The study reported that eating two whole apples a day reduced LDL (bad) cholesterol with no negative effect on HDL (good) cholesterol.
Although this was a small study, compared to other studies that focused on fresh apple consumption, it had a decent sample size and good compliance from the volunteers. The volunteers were not blinded to the different interventions but were told that either the whole apple of the apple drink may be helpful. In reality, it was the whole apple that was beneficial.
In addition to lowering bad cholesterol, it was found that apples improve cardiovascular health by reducing total cholesterol and increasing microvascular vasodilation (widening of the blood vessels). Widening of the blood vessels leads to greater blood flow, naturally lowering blood pressure. High cholesterol and high blood pressure are both risk factors for cardiovascular disease such as stroke, therefore by lowering both of these risk factors apples can improve cardiovascular health.
Rich in fibre, vitamins, and antioxidants apples have been at the centre of many research studies. Consuming the whole fruit has also been found to aid in weight loss and help reduce the risk of type 2 diabetes. This new research study is another positive addition to the health benefits of apple consumption, suggesting that an apple a day (or in this case two apples a day) really can keep the doctor away.
Written by Helen Massy, BSc
Hu, F. (2003). Plant-based foods and prevention of cardiovascular disease: an overview. The American Journal of Clinical Nutrition, 78(3), pp.544S-551S.
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