Articles

Does An Apple a Day Really Work?

By Tiffany Spudich, R.Ph., Pharm. D.

You may have heard the old proverb "An apple a day keeps the doctor away," but may have wondered the basis for this statement or if there is even any truth to it. Evidence suggests that a diet high in fruits and vegetables may decrease the risk of chronic diseases, such as cardiovascular disease and cancer, and phytochemicals including phenolics, flavonoids and carotenoids from fruits and vegetables may play a key role in reducing chronic disease risk. Apples are a widely consumed, rich source of phytochemicals, and studies have linked the consumption of apples with reduced risk of some cancers, cardiovascular disease, asthma, and diabetes. In the laboratory, apples have been found to have very strong antioxidant activity, inhibit cancer cell proliferation, and lower cholesterol. In the United States, twenty-two percent of the phenolics consumed from fruits are from apples, making them the largest source of phenolics.

Not only are apples a good source of phenolics, but they are also a good source of antioxidants. When compared to many other commonly consumed fruits in the United States including red grapes, bananas, oranges, and grapefruit, apples had the second highest levels of antioxidant activity, with only cranberries demonstrating higher activity. Apples contain a variety of phytochemicals, including quercetin, catechin, phloridzin and chlorogenic acid, all of which are strong antioxidants. Since fruits and vegetables are high in antioxidants, a diet high in these foods could help prevent chronic disease and slow aging. These findings are part of the basis for the National Research Council to recommend consuming five or more servings of fruits and vegetables a day.

If you have every contemplated whether to peel or not to peel that apple, there is no question here. Whenever possible, do not peel that apple. Two-thirds of the fiber and many of the antioxidants are found primarily in apple's peel. Research has shown that apple peels contain anywhere from two to six times more phenolic compounds and antioxidants than in the flesh, depending on the variety of apples, and two to three times more flavonoids in the peels when compared to the flesh.

Furthermore, the phytochemical and antioxidant composition of apples varies between different varieties of apples. Out of ten apple varieties commonly consumed in the US, Fuji apples had the highest total phenolic and total flavonoid compounds. Red Delicious apples were also quite high, and the apples containing the lowest levels of these compounds were Empire apples and the NY647 apples. The apple varieties with the higher phenolics tended to also have higher antioxidant activity. Storage of apples does not seem to greatly affect apple phytochemical content, but the processing of apples for juice appears to result in a significant decrease in phenolics.

Overall, the potential health benefits of apples are numerous. Regular consumption of fruits and vegetables, including apples, as part of a healthy diet may aid in the prevention of chronic disease and maintenance of good health. According to the food pyramid provided by the United States Department of Agriculture (USDA), most men and women need approximately 2 cups of fruit per day. Unfortunately, apples do no usually come measured by the cup, so what counts as 1 cup of fruit? Generally speaking, one apple, one cup apples slices, one cup apples juice, or one cup of applesauce would each make one cup. Below are some tips for incorporating more apples into one’s daily diet:

Breakfast:

• Chopped apples in oatmeal
  
• Applesauce as a topping on whole grain pancakes, waffles, or French toast
  
• A glass of apple juice with a whole grain bagel
  
• Apple juice, berries and yogurt blended into a smoothie
  

• Apple slices on a peanut butter sandwich
  
• Chopped apples in chicken or tuna salad
  
• Apple slices and low fat cheese melted on a whole wheat English muffin
  
• Applesauce instead of chips or cookies
  
• Apple juice instead of soda
  

• Apple wedges with peanut butter
  
• Apple slices with low fat cheese
  
• Dried apples mixed with dry cereal and nuts for trail mix
  
• Apple slices dipped in fat-free caramel topping
  

• Apple chunks, walnuts, and mixed greens tossed in a light vinaigrette
  
• Pork tenderloin baked with apple wedges and apple cider
  
• Roasted chicken with chopped apples, raisins and whole grain bread stuffing
  
• Baked apples with cinnamon
  

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