Apples really are healthy food. They provide fiber and nutrients without a large amount of calories. Including them in your diet can contribute to a healthy lifestyle.
a survey of eating and health habits, found that people who had eaten apples in any form over the past day were 27 percent less likely to have symptoms of metabolic syndrome than those who didnât. The apple eaters also had lower levels of C-reactive protein, a marker of inflammation whose presence in the blood suggests an increased risk for heart disease and diabetes.
“Our study suggests  that ursolic acid increases skeletal muscle and brown fat leading to increased calorie burning, which in turn protects against diet-induced obesity, pre-diabetes and fatty liver disease,” Christopher Adams, M.D., Ph.D., UI associate professor of internal medicine at the University of Iowa.
Until quite recently, researchers believed that only infants had brown fat, which then disappeared during childhood. However, improved imaging techniques have shown that adults do retain a very small amount of the substance mostly in the neck and between the shoulder blades. Some studies have linked increased levels of brown fat with lower levels of obesity and healthier levels of blood sugar and blood lipid, leading to the suggestion that brown fat may be helpful in preventing obesity and diabetes.