Apples: Health benefits, facts, research

Apples are sometimes called "nutritional powerhouses" because of their impressive nutritional profile.

Apples contain about 14 percent of our daily needs of Vitamin C (a powerful natural antioxidant), B-complex vitamins, dietary fiber, phytonutrients (which help protect the body from the detrimental effects of free radicals), and minerals such as calcium and potassium.

Studies have revealed that eating apples can potentially help prevent dementia and reduce the risk of stroke and diabetes.

"An apple a day keeps the doctor away" is an old Welsh proverb that most of us are familiar with, but what makes this fruit so special? What health benefits are associated with eating apples?

As one of the most cultivated and consumed fruits in the world, apples are continuously being praised as a "miracle food".

In fact, apples were ranked first in Medical News Today's featured article about the top 10 healthy foods.

Apples are extremely rich in important antioxidants, flavanoids, and dietary fiber.

The phytonutrients and antioxidants in apples may help reduce the risk of developing cancer, hypertension, diabetes, and heart disease.

This article provides a nutritional profile of the fruit and its possible health benefits. It also discusses the possible risks and precautions and some frequently asked questions.

Possible health benefits of apples

A collection of research studies suggests that apples may well be one of the most healthy foods for you to include in your daily diet. Let's take a look at the studies and the possible health benefits suggested by them:

Improving neurological health

A 2006 study published in the journal Experimental Biology and Medicinefound that quercetin (one of the antioxidants found abundantly in apples) was one of two compounds that helped to reduce cellular death that is caused by oxidation and inflammation of neurons. 

Another study presented at the same conference and published in the Journal of Alzheimer's Disease suggested that apple juice consumption may increase the production in the brain of the essential neurotransmitter acetylcholine, resulting in improved memory among mice who have Alzheimer's-like symptoms. 

It should be noted that both studies were funded by unrestricted grants provided by the U.S. Apple Association and Apple Products Research and Education Council.

Preventing dementia

A study published in the Journal of Food Science in 2008 suggested that eating apples may have benefit for your neurological health.

The researchers found that including apples in your daily diet may protect neuron cells against oxidative stress-induced neurotoxicity and may play an important role in reducing the risk of neurodegenerative disorders such as Alzheimer's disease.

Reducing your risk of stroke

A study involving 9,208 men and women showed that those who ate the most apples over a 28-year period had the lowest risk for stroke.

The researchers concluded that the intake of apples is related to a decreased risk of thrombotic stroke.4

Lowering levels of bad cholesterol

A group of researchers at The Florida State University stated that apples are a "miracle fruit".

They found that older women who ate apples everyday had 23% less bad cholesterol (LDL) and 4% more good cholesterol (HDL) after just six months.

Reducing your risk of diabetes

Apples could also help lower your risk of diabetes. A study involving 187,382 people found that people who ate three servings per week of apples, grapes, raisins, blueberries or pears had a 7% lower risk of developing type 2 diabetes compared to those who did not.

Warding off breast cancer

There is growing evidence suggesting that an apple a day may help prevent breast cancer, according to a series of studies conducted by prominent Cornell researcher Rui Hai Liu.

Liu said her research adds to "the growing evidence that increased consumption of fruits and vegetables, including apples, would provide consumers with more phenolics, which are proving to have important health benefits. I would encourage consumers to eat more and a wide variety of fruits and vegetables daily."

Obesity

In a study published in the journal Food Chemistry in 2014, a team of researchers analyzed how the bioactive compounds of seven different varieties of apples - Granny Smith, Braeburn, Fuji, Gala, Golden Delicious, McIntosh and Red Delicious - affected the good gut bacteria of diet-induced obese mice.

The researchers found that, compared with all other apple varieties, Granny Smiths appeared to have the most beneficial effect on good gut bacteria. They suggest that their findings may lead to strategies that prevent obesity and its associated disorders.

Nutritional profile of apples

Apples contain almost no fat, sodium or cholesterol.

Apples deserve to be called "nutritional powerhouses". They contain the following important nutrients:

• Vitamin C - a powerful natural antioxidant capable of blocking some of the damage caused by free radicals, as well as boosting the body's resistance against infectious agents, according to the University of Maryland Medical Center.
• B-complex vitamins (riboflavin, thiamin, and vitamin B-6) - these vitamins are key in maintaining red blood cells and the nervous system in good health.
• Dietary fiber - the British National Health Service2 says that a diet high in fiber can help prevent the development of certain diseases and may help prevent the amount of bad cholesterol in your blood from rising.
• Phytonutrients - apples are rich in polyphenolic compounds". These phytonutrients help protect the body from the detrimental effects of free radicals.3
• Minerals such as calcium, potassium, and phosphorus.

Apples, with skin (edible parts) nutritional value per 100 grams

Energy - 52 kcal	Carbohydrates - 13.81 g
Fat - 0.17 g	Protein - 0.26 g
Water - 85.56 g	Sodium - 1 mg
Beta-carotene - 27 μg	Lutein and zeaxanthin - 29 μg
Thiamin (vitamin B1) - 0.017 mg	Vitamin A equiv - 3 μg
Riboflavin (vitamin B2) - 0.026 mg	Niacin (vitamin B3) - 0.091 mg
Pantothenic acid (vitamin B5) - 0.061 mg	Vitamin B6 - 0.041 mg
Folate (vitamin B9) - 3 μg	Vitamin C - 4.6 mg
Vitamin E - 0.18 mg	Vitamin K - 2.2 μg
Calcium - 6 mg	Iron - 0.12 mg
Magnesium - 5 mg	Manganese - 0.035 mg
Phosphorus - 11 mg	Potassium - 107 mg

Note: the average size of an apple is 150 grams
Source: USDA

Risks and precautions

No serious side effects are linked to apple consumption.

Apple seeds contain contain cyanide, a powerful poison. Eating too many apple seeds can potentially be fatal. Apple seeds should not be consumed.

In addition, because apples are fairly acidic, they could be up to four times more damaging to teeth than carbonated drinks, according to a study led by Professor David Bartlett at the King's Dental Institute.5

Professor Bartlett said that "snacking on acidic foods throughout the day is the most damaging, whilst eating them at meal times is much safer. It's not what you eat it's how you eat it - an apple a day is good, but taking all day to eat the apple can damage teeth."

Apples - three frequently asked questions

Should I eat the apple peel? - Most of the fiber and antioxidants are in the peel, says Dianne Hyson, Ph.D., R.D.6, a research dietitian at UC Davis in the Department of Internal Medicine.

What about pesticides on the peel? - Dr. Hyson says "Despite public misperceptions, laboratories have consistently found very low levels - if any - of pesticide residues on the skin of apples."

I have type 2 diabetes, can I eat apples? - According to the American Diabetes Association, "Apples are a nutritious food and you can still eat them even if you have diabetes." The Association reminds people to eat the peel and advises on buying small apples (2.5 inches in diameter).