We’ve all heard the expression, “An apple a day keeps the doctor away.” And it turns out it’s true — apples have many health benefits that could potentially keep you out of the doctor’s office. Thanks to a clinical review conducted by researcher Dianne A. Hyson from California State University in Sacramento, we now have a much broader understanding of the sheer number of health advantages that come along with consuming apples and apple products.
What Makes Apples So Nutritious?
Apples are a rich source of dietary polyphenols, which are one type of free radical-fighting antioxidants in the body. This high polyphenol content in apples is what makes them so protective, nutritious, and delicious.
The two biggest subclasses of polyphenols in apples are flavonoids and phenolic acids. Flavonoids are further broken down into more than 4,000 categories, three of the most abundant in apples being flavanols, flavonols and anthocyanidins.
Let’s take a look at how this high polyphenol content translates to protection against some of the most common and dangerous health conditions out there — cancer, cardiovascular disease, diabetes and osteoporosis.
The American Institute for Cancer Research estimates that one-third of all cancer cases could be prevented by an improved diet, especially higher fruit, vegetable and whole grain consumption. Several studies have shown that apples, in particular, are associated with reduced risk of cancer.
In one such study, researchers examined fresh apple intake and cancer risk of more than 6,000 Italian participants. They found that eating one or more medium-sized apples (approximately 166 grams, or just shy of 6 ounces) per day was associated with a decreased cancer risk compared to eating less than one apple per day.
The biggest risk reduction was seen in cancer of the larynx (41 percent), colon/rectum (30 percent), breast (24 percent), ovary (24 percent), and esophagus (22 percent).
Most recent estimates state that 80 millions Americans have some type of cardiovascular disease, including hypertension (high blood pressure), coronary artery disease, myocardial infarction, angina, heart failure and stroke.
Oxidative damage appears to be a top cause of cardiovascular disease due to the destruction of DNA and other cellular components. Antioxidants, such as those found in apples, are so important because they scavenge free radicals and counteract oxidative damage.
In one Turkish study, 15 participants who ate fresh apples (on average one a day) every day for one month were shown to have had increased antioxidant enzymes in their bodies.
And in another study, 10 participants in Japan were given 150 mL (about 5 ounces) of apple juice, and then had antioxidant levels checked in their blood. Researchers found that apple juice was among eight fresh fruit juices tested to exhibit an antioxidant effect within 30 minutes of consumption that lasted for up to an hour and a half!
Elevated “bad” LDL cholesterol levels are a significant risk factor for cardiovascular disease, and apples have also been shown to improve lipid profiles.
In one study, hamsters were given either apples to approximate human intake of 600 grams (21 ounces) per day, or apple juice to approximate 500 mL (17 ounces) per day. After 12 weeks, both the apples and the apple juice significantly reduced cholesterol (11 percent and 24 percent, respectively) and lowered the ratio of total cholesterol to “good” HDL cholesterol (25 percent and 38 percent, respectively).
The incidence of type 2 or “adult onset” diabetes is rising at an alarming rate, thanks to poor diet choices, lack of exercise, and the resulting obesity.
To see what effect apples had on diabetes risk, researchers examined women in a large, ongoing trial called the Women’s Health Study. They identified apples as the only flavonoid-rich food that could potentially have protective capabilities. Compared to no apple consumption, the consumption of two to six apples per week led to a 27 percent lower risk of type 2 diabetes, while one apple per day decreased the risk by 28 percent.
Approximately 10 million Americans suffer from osteoporosis, and fruits and vegetables are thought to provide many of the nutrients necessary for strong, healthy bones. Only a few studies have examined apples and apple products specifically in relation to bone health, but preliminary results show great promise.
In one crossover study, 15 female participants each consumed a meal on three different occasions that consisted of either fresh, peeled apples, unsweetened apple sauce, or candy.
Urine samples collected at 1.5, 3, and 4.5 hours after consumption showed that the meals that included apples and apple sauce resulted in less calcium loss compared to the control (candy) meal.
Develop an Appetite for Apples
In addition to these four conditions, the author of this review also determined that apples and apple products have beneficial effects on Alzheimer’s disease, cognitive decline associated with normal aging, weight management and asthma.
What’s most exciting about all of this research is that achieving these great results is so simple. It really does take about one apple a day to experience the wonderful protective benefits against cancer, heart disease, diabetes and osteoporosis.
Not only that, but your choices for apples are practically endless: Granny Smith, Macintosh, Red Delicious, Golden Delicious, Pink Lady, Cameo, Braeburn and Gala are just a few of the literally thousands of choices available to you. And, unlike many fruits, apples are always “in season” and available year-round. Just try to purchase certified organic or pesticide-free apples whenever possible, as apples tend to have higher pesticide residue levels than other fruits and vegetables.
Whole fruits are always the best option when it comes to nutritional value, but as many of these studies showed, even processed apple foods like applesauce and apple juice had antioxidant capabilities. But remember, if you choose to eat or drink processed apple products, be sure to choose sugar-free or reduced sugar versions because these options are often high in sugar.
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