In a previous post I shared new research linking stone fruits like peaches and cherries to weight control. Now apples are the hot topic of the day. A new study from the University of Iowa found that a natural substance in apple peel called ursolic acid protected mice from obesity and its harmful effects.
Previous research has shown that ursolic acid increased muscle mass in healthy mice. In the new study, scientists gave the compound to mice fed a junk food diet. Not only did the supplement boost muscle, it also reduced obesity, pre-diabetes and fatty liver disease. Interestingly, the group of mice who received ursolic acid in their fattening food ate more than those who didn’t get the supplement, and there was no difference in physical activity between the two groups. But the ursolic acid-fed mice gained less weight and their blood sugar level remained close to normal.
Intriguing study, but I wouldn’t recommend running out to buy an apple peel supplement just yet. Until we have more research on the safety and proper dosage just continue to eat apples, which offer lots of proven benefits, including:
A medium apple packs 5 grams of fiber, 20 percent of the minimum daily target. Not only is fiber filling but it also helps keep blood cholesterol under control to reduce the risk of heart disease and offers weight control benefits. Research has shown that for every gram of fiber we eat, we eliminate about seven calories. That means if you eat 30 grams a day you’ll essentially "cancel out" 210 calories, a savings that could result in a 20 pound weight loss in one year's time. Another study in Brazilian dieters found that over a six month period, each additional gram of fiber resulted in an extra quarter pound of weight loss.
Blood sugar regulation
Apples also supply unique substances, which have been linked to blood sugar regulation. Scientists believe that a key antioxidant in apples blocks the activity of an enzyme responsible for breaking starch into simple sugar. This means that fewer simple sugars are released into the blood stream, lowering blood sugar and the corresponding insulin response.
Several studies have tied eating apples, including the skins, to better lung function and a lower risk of respiratory diseases including asthma, bronchitis, and emphysema. In fact, one study found that apples helped reduce the risk of asthma more than other fruits and veggies combined.
One of my favorite ways to enjoy an apple, including the skin, is to chop, toss with a little lemon juice and cinnamon, bake in the oven or warm in the microwave to soften, and sprinkle with a topping made from a mixture of rolled oats and almond butter. It’s like a healthy version of warm apple crumble!
Cynthia Sass is a registered dietitian with master's degrees in both nutrition science and public health. Frequently seen on national TV, she's a SHAPE contributing editor and nutrition consultant to the New York Rangers and Tampa Bay Rays. Her latest New York Times best seller is S.A.S.S! Yourself Slim: Conquer Cravings, Drop Pounds and Lose Inches.