8 Awesome Benefits of Eating an Apple a Day

Research indicates that an apple a day really does keep the doctor away. It also helps build muscle and enhances memory.

Apples are awesome. They're portable, delicious, and, according to research, they deliver tons of helpful nutrients that can help you regulate your appetite, steer clear of illness, and even add muscle. Whether you're already an apple lover or someone who needs more reasons to up his or her fruit intake, here are eight powerful reasons why you should be eating more of America's second-favorite fruit.

1. Apples Assist With Appetite Control

Apples Assist With Appetite Control

Apples are ridiculously high in dietary fiber. A typical serving contains 6 grams—nearly a quarter of your recommended daily value.

A diet high in fiber has numerous benefits. According to the Mayo Clinic, it can help normalize bowel movements, lower cholesterol levels, control blood sugar, maintain bowel health and aid in achieving a healthy weight. The Harvard School of Public Health states that fiber appears to reduce the risk of heart disease, diabetes and cardiovascular disease.

One of the most interesting effects of fiber is that it slows down digestion, which helps you feel fuller longer after you eat. This can be a great benefit for people who want to cut calories and lose weight—or for anyone looking for an afternoon snack to hold them over until dinner!

2. Apples Boost Your Mood

Apples Boost Your Mood

In a 2013 study entitled "Many apples a day keep the blues away—daily experiences of negative and positive affect and food consumption in young adults," researchers at the University of Otago in New Zealand found that eating more fruits and vegetables boosted the mood, happiness and energy of young people.

The study's participants (whose mean age was 20) were asked to appraise their feelings and enter them in a diary every night for 21 consecutive days. They also were asked specific questions about the foods they had eaten that day.

Researchers found that on the days participants ate more fruits and veggies, they felt significantly better. "On days when people ate more fruits and vegetables, they reported feeling calmer, happier and more energetic than they normally did," said lead author Dr. Tamlin Conner.

3. Apples Lower your Bad Cholesterol

Apples Boost Your Mood

A 2012 study out of The Ohio State University found that eating one apple a day for four weeks greatly reduced participants' levels of oxidized LDL (low-density lipoprotein), a type of cholesterol that's more likely to promote inflammation than unoxidized LDL.

"When LDL becomes oxidized, it takes on a form that begins atherosclerosis, or hardening of the arteries," said lead researcher Robert DiSilvestro. Hardened arteries can lead to a variety of conditions, including blood clots, heart attack and stroke.

Participants in the study were nonsmoking healthy adults between the ages of 40 and 60 who had a history of eating apples less than twice a month. By eating an apple every day, they were able to lower their oxidized LDL by an average of 40 percent in just four weeks.

4. Apples Can Help Build Muscle and Prevent Obesity

 Apples Can Help Build Muscle and Prevent Obesity

A 2012 animal study at the University of Iowa found that a natural substance in apple peel called ursolic acid may help protect against obesity.

The study examined a group of mice who ate a high-fat diet over a period of several weeks. Half the mice received ursolic acid in their high-fat food while the other half did not. The mice whose diet contained ursolic acid experienced a greater increase in skeletal muscle and brown fat, both of which can increase calorie-burning.

The mice who consumed ursolic acid actually ate more food than the mice who did not; and although they had the same level of activity, they gained less weight. They also had a reduced risk of obesity, pre-diabetes and fatty liver disease.

"Our study suggest 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," said the study author.

5. Apples Help Ward Off Cancer

Apples Help Ward Off Cancer

According to the American Institue of Cancer Research, dietary fiber "convincingly" lowers the risk of colorectal cancer, and  vitamin C—of which an apple supplies about 18 percent of your daily value—"probably" lowers the risk of esophageal  cancer. Fruits in general "probably" lower the risk of lung, stomach, mouth, pharynx, larynx and esophagus cancer, according to the institute.

6. Apples Sharpen Your Memory

Apples Sharpen Your Memory

Apples and apple juice could help your memory stay sharp as you grow older. A 2006 animal study at the University of Massachusetts-Lowell found that apple juice consumption increased the brains levels of acetlycholine, which is an essential neurotransmitter.

Neurotransmitters are chemicals released by nerve cells to transmit messages to other nerve cells. "Such communication between nerve cells is vital for good health, not just in the brain, but throughout the body," UMass-Lowell stated in a press release outlining the study's findings.

When mice who were specifically bred to develop Alzheimer's-like symptoms were fed a diet supplemented with apple products, they performed significantly better in memory-related tests than mice who did not eat such a diet. They were also found to have increased production of acetlycholine.

2004 animal study at Cornell University found that the antioxidant quercetin helped prevent oxidative stress, which damages brain tissues and is associated with neurodegenerative disorders. It so happens that apples (and in particular, apple skin) are packed with quercetin.

"On the basis of serving size, fresh apples have some of the highest levels of quercetin when compared to other fruits and vegetables and may be among the best food choices for fighting Alzheimer's," said study leader C.Y. Lee.

7. Apples Could Strengthen the Immune System

 Apples Could Strengthen the Immune System

Quercetin, the antioxidant in apples that helps protect the brain, may also be capable of strengthening your immune system.

According to the University of Maryland Medical Center, quercetin has shown impressive allergy-fighting characteristics in lab studies. "In test tubes, quercetin prevents immune cells from releasing histamines, chemicals that cause allergic reactions." On that basis, researchers think that quercetin may help reduce symptoms of allergies, including runny nose, watery eyes, hives and swelling of the face and lips.

8. Apples Increase Your Energy

Apples are a great source of simple carbohydrates, which can be turned into energy quickly. Thus, apples make an excellent choice for an afternoon or pre-workout snack.

The fruit's high fiber content helps you feel satiated without feeling bogged down, which is exactly what you want from a snack when you're on the go.

Combine apples with a healthy fat source—such as pistachios or peanut butter—for a supercharged snack that will keep you going strong for a long time.

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