Apples are loaded with vitamin C. Almost half of an apple’s vitamin C content is just under the skin, so it’s a good idea to eat apples with their skins. Flores said that this is also where apples’ fiber is found. Apples contain insoluble fiber, which provides bulk in the intestinal tract. The bulk holds water that cleanses and moves food quickly through the digestive system.
According to Flores, “Regular intake of apples has been shown to have cardiovascular benefits. [This is due to] two properties of apples: the fiber that they contain and the polyphenols that are found in high amounts.”
In addition to digestion-aiding insoluble fiber, apples have soluble fiber, such as pectin. This nutrient helps prevent cholesterol from building up in the lining of blood vessels, which in turn helps prevent atherosclerosis and heart disease. In a 2011 study, women who ate 75 grams of dried apples every day for six months had a 23 percent decrease in bad LDL cholesterol, said study researcher Bahram H. Arjmandi, professor at and chair of the department of nutrition at Florida State University. Additionally, the women’s levels of good HDL cholesterol increased by about 4 percent, according to the study.
When it comes to polyphenols and antioxidants, Flores explained that they “work in the cell lining to decrease oxidation resulting in lowering risk of cardiovascular disease.”
Another study tracked food consumption among 9,208 people for 28 years. Those who ate more apples had a lower risk of stroke. Researchers attributed the results to quercetin, an antioxidant in apples.
There are respiratory benefits to eating apples, as well. “Apples’ antioxidant benefits can help lower the risk of asthma,” Flores told Live Science. Also, a study of 2,500 middle-aged men in Wales found improved lung function among those who ate an apple a day, according to the University of California, Davis. A study in Brazil showed that adding three apples a day to women’s diets helped lower their calorie intake and contributed to weight reduction.
Apples and cancer
The American Institute for Cancer Research recommends eating lots of fruits and vegetables, including apples. The antioxidant content of apples ranks among the highest for fruits, and research shows that antioxidants help prevent cancer.
Lung cancer risk can especially be lowered through apples’ antioxidants, according to Flores. A study in Hawaii found that people who regularly eat apples, onions and white grapefruit cut their lung cancer risk in half.