Can Eating An Apple A Day Keep The Doctor Away?

Reviewed by Madhu Sharma, Registered Dietitian
by Swathi Handoo

Apples are the cheapest and wholesome sources of nutrition available throughout the year. They are high in antioxidants, vitamins, minerals, and fiber. That’s why eating them may prevent chronic diseases of the heart, brain, GI tract, bones, and eyes.

Read this article to find science-backed answers to a few myths you’ve heard since your childhood. Swipe up!

Why Should You Eat Apples? What Do They Contain?

Apple (Malus domestica) is one of the top three fruits produced around the world. It is easy to store and transport and available almost round the year (1).

This fruit is rich in carbohydrates, fiber, vitamins, and phytochemicals. Its polyphenols have excellent antioxidant capacity (2).

As per research and medical literature, apples are among the foods that show direct and strongest associations with decreased mortality. In fact, the National Research Council recommends at least 5 servings of fruits and veggies a day, and apples are one of them (2).

Apples predominantly contain pectin and quercetin. Pectin is a type of soluble fiber that may help ease digestion. Quercetin is a flavonoid that has antioxidant and anti-inflammatory effects (1).

All these reasons are behind the famous proverb: An apple a day keeps the doctor away.

Move on to the next section to understand how apples benefit your health. You can also find supporting scientific evidence for each of the benefits. Scroll down!

What Are The Health Benefits Of Apples?

These crunchy fruits have potent anti-aging effects. They may prevent age-related memory loss, skin troubles, and hair fall. Eating them in the right amounts may also reduce the risk of cancers.

1. May Protect Your Heart

A few studies relate high flavonoid intake to a reduced risk of cardiovascular diseases of about 35%, particularly in women. Finnish research shows a similar relation between thrombotic stroke and apple consumption (2).

In older men and nearly 35,000 women, apples and wine (and not juice) prevented coronary heart disease, myocardial infarction (heart attack), and death. According to animal studies, the active ingredients in the peel and fruit have a cholesterol-lowering effect (1), (2).

They protect the heart and blood vessels from free radical damage that triggers most of the cardiovascular diseases. However, a significant chunk of evidence indicates mixed results of apple intake and heart health. Some researchers claim the data to be statistically insignificant (1), (2).

2. May Maintain Brain Health

Apple polyphenols may protect your brain from neurodegenerative diseases like Alzheimer’s and Parkinson’s and age-related memory loss. Lab studies at Cornell University propose quercetin and phenolic acids to be primarily involved in this property (3).

Apple juice concentrate rectifies folate deficiency that could cause age-related neurodegeneration. It reduces the accumulation of proteins (like amyloid-beta) that trigger Alzheimer’s disease (4).

It also eliminates free radicals, thereby slowing down cognitive decline. The extract maintains the levels of the neurotransmitter acetylcholine, which is low in deficient and aged subjects (5).

3. May Reduce Acne And Treat Aging Skin

Flavonoids like phlorizin, apigenin, silymarin, and genistein naturally occur in fruits like apple, cherry, and pear. Phlorizin has been extensively studied for its anti-aging effects on the skin (6).

Apigenin, genistein, and other polyphenols protect your skin from the sun and the UV ray-induced inflammation and dark/white spots. They also control the secretion of sebum and hence can help in managing acne vulgaris (7).

One cup of raw apple slices (with skin) has about 5 mg of vitamin C. This vitamin rejuvenates your skin with its antioxidant effects. Therefore, topical and oral use of vitamin C-rich apples hydrates your skin and may prevent skin cancers (6), (8).

4. May Aid Weight Loss

A cup of apple slices (with skin) has 2.6 g of dietary fiber. Fiber slows down digestion, inducing a sense of satiety (fullness). According to studies, having more fiber-rich foods like apples is associated with the least amount of weight gain over time (1), (8).

Moreover, the glycemic index of raw apple and apple juice is about 36 (±2) and 41 (±2), respectively. Both these foods produce fewer and smaller spikes in blood sugar levels. This may lessen hunger pangs and prevent overeating. Thus, your weight gain would be in check (1), (9).

But how long should one consume apples to reduce body fat is still not clear (10).

5. May Regulate Diabetes

An epidemiological study of about 38,000 women spanning over 9 years showed a positive relation between apple intake and type 2 diabetes. Those who ate 1-2 apples a day had 28% lower risk of type 2 diabetes compared to those who ate none (1).

The apple flavonoids could be responsible for this, given their antioxidant effects. These active ingredients protect the cells in the pancreas from damage (1).

Despite having 15% carbohydrates, apples have a relatively low glycemic index. You may add them to a diabetic-friendly diet (1). However, consult your doctor as they would know what’s best for you.

6. May Promote Digestion And Gut Health

Apples are rich in polyphenols, carbohydrates, and fiber. A major proportion of the polyphenols and fiber directly reach the colon. They are fermented by the good gut bacteria that survive on the derived energy (11).

The insoluble fiber of apples, especially the pectin and hemicellulose, are converted to short-chain fatty acids (SCFAs). SCFAs, in turn, promote the growth of intestinal microbes. They also maintain the ratio between the two important classes of gut bacteria, Firmicutes and Bacteroidetes (11).

The fiber doubles up as a bulking agent. It holds/retains water to cleanse and rectify the bowel movement (12).

7. Have Anti-inflammatory Properties

Chronic inflammation is linked to diabetes, cardiovascular disease, irritable bowel disease (IBD), Alzheimer’s, arthritis, asthma, Crohn’s disease, etc. You can control the severity of such inflammatory diseases by adding apples to your diet (13), (14).

Raw, unpeeled apples contain polyphenols that inhibit the production of pro-inflammatory compounds. Apple juice may possess flavonoid derivatives like procyanidin and phloretin. These active molecules can bring down the expression of genes responsible for inflammation (14), (15).

8. May Boost Eye Health And Vision

Vitamins A and C and quercetin protect your eyes from age-related degeneration and other eye infections. Carotenoids like lutein and zeaxanthin are vital for color detection in the retina. They are potent antioxidants too. Consuming foods rich in these components is the only way to maintain their levels in the macula of the retina (16).

Red apples with skin are abundant in almost all of these micronutrients. They have 15 μg/100 g of lutein, 18 μg/100 g of ß-carotene, 54 IU/100 g of vitamin-A, and 4.6 mg/100 g of vitamin-C. Studies have proven the therapeutic effects of having these fruits on eye disorders like cataracts and macular degeneration in the elderly (8), (17).

9. May Be Good For Bones And Teeth

Apples are great sources of minerals. They contain boron, potassium, calcium, and fair amounts of zinc, and these are necessary for bone health (18).

Pears, apples, prunes, berries, tomatoes, etc. should be a mandatory addition to the diet of post-menopausal women (and older men). The antioxidants in these fruits can prevent/delay osteoarthritis, osteoporosis, and other bone diseases (18).

While sugary apple juice may contribute to tooth decay, fresh apples are less likely to cause such problems. These fibrous fruits increase salivation and neutralize the acidic environment in your mouth. Chewing on them also lessens cavities (19).

10. May Promote Hair Growth

Annurca apple, native to Southern Italy, contains a polyphenol called Procyanidin B2 in abundance. Procyanidin B2 has been studied extensively for its effect on hair growth. It is said to stimulate the proliferation of hair follicles and keratin production (20), (21).

Healthy subjects were given a fixed oral dose of Annurca apple extract in a study. After two months, they showed increased hair growth, hair number, hair weight, and keratin content (20).

Apple cider vinegar is widely used in hair care products to prevent hair fall and dandruff. However, there isn’t enough research supporting this property.

11. May Reduce Cancer Risk

Clinical trials suggest that consuming apples reduce the risk of cancer. High consumption of apples may reduce the risk of lung, colorectal, and GI tract cancers. Some animal studies demonstrate the anti-cancer effect of this fruit on breast cancer cells (22), (23), (24).

Apple flavonoids have the second highest level of antioxidant power among all fruits. Their peels have stronger antioxidant capacity than the flesh (23).

These antioxidants scavenge free radicals that damage healthy cells and DNA. They also stop the production of these reactive/toxic substances. That is why the tumor incidence in the subjects was reduced by 17% when they had one apple a day for over 24 weeks (24).

Check out the next section for a complete list of nutrients in apples.

Nutrition Profile Of Apples

APPLE, raw
Serving size1 medium (3″ dia) or 182 g
NutrientAmount per serving
Proximates
Energy (kcal)95
Protein (g)0.47
Fat, total (g)0.31
Carbohydrate (g)25.13
Sugars, total (g)18.91
Fiber, total dietary (g)4.4
Cholesterol (mg)0
Minerals
Calcium (mg)11
Copper (mg)0.049
Iron (mg)0.22
Magnesium (mg)9
Phosphorus (mg)20
Potassium (mg)195
Sodium (mg)2
Zinc (mg)0.07
Vitamins
Vitamin A, RAE (mcg)5
Vitamin C (mg)8.4
Vitamin B-6 (mg)0.075
Choline, total (mg)6.2
Vitamin E, alpha tocopherol (mg)0.33
Folate, DFE (mcg)5
Folate, food (mcg)5
Folate, total (mcg)5
Vitamin K (mcg)4
Niacin (mg)0.166
Riboflavin (mg)0.047
Thiamin (mg)0.031
Carotene, beta (mcg)49
Cryptoxanthin, beta (mcg)20
Lutein + zeaxanthin (mcg)53

Apples are one of the richest fruits in terms of phytochemical composition. They contain significant amounts of flavonoids and phenolic acids (2).

Some of the most-studied compounds include quercetin derivatives, catechin, epicatechin, procyanidin, cyanidin, coumaric acid, chlorogenic acid, gallic acid, and phloridzin (2).

Apple peel has procyanidins, catechin, epicatechin, chlorogenic acid, phloridzin, and quercetin. Quercetin derivatives are found exclusively in the skin (2).

In the flesh, catechin, procyanidin, epicatechin, and phloridzin are present in fair amounts. But chlorogenic acid tends to be higher in the flesh than in the peel (2).

Research showed that apples without the peels had less antioxidant activity than apples with the peels. So, make eating apples a habit. They can repair and maintain almost every organ system of your body.

Now, for the most important question:

How Many Apples Should You Eat In A Day?

The fruit recommendation for children is age and gender-dependent. It lies between 1.5-2 cups for most children over 4 years.

For young adults and above, the Dietary Reference Intakes (DRI) for fiber is set to 25-30 g/day. Apples (with skin) contain a mix of insoluble (3.1 g/1 medium apple) and soluble (1.3 g/1 medium apple) fiber.

Considering fiber intake from other sources like vegetables, juices, and meat, eating 2-3 small-sized apples or 1 medium-large sized apple a day seems ideal.

How About The Pesticides On The Peel?

Eating an apple with its skin is recommended. But it is shown to have deposits of harmful pesticides. Does that mean you peel the fruit?

Not necessarily.

Many countries have taken strict action against this. There are various pretreatment measures the farmers and the government have to consider before releasing a batch of apples into the markets.

Moreover, you can follow these tips to get rid of pesticides on apples:

  • Buy only organic produce.
  • While washing, brush the surface of the fruits with a clean food-grade brush.
  • Do not use detergents or soap. Washing is primarily meant to kill the bacteria.
  • Water is just as, if not more, effective than any produce wash.
  • Baking soda can be used. Soak the apple in a baking soda solution of 1 teaspoon of baking soda and 2 cups water for 10-15 minutes. Rinse well. Towel dry the fruits.
  • You can pretreat a big batch of apples before storing them.

What Is The Best Way To Have Apples?

You can find a thousand apple products on the market. More than 50% contain just of the synthetic flavor/essence. Coming to the actual apple-based products, you can choose between the whole-fresh fruit, apple juice, apple sauce, pies, and many more.

However, the best way to tap all the benefits of apples is by eating fresh, whole fruits (along with the skin). Whole fruits have maximum nutrients and almost no contamination (25)

100% apple juice is another option you could go for. But several studies link its consumption to obesity and stunted growth in children. So, even if consumed in excess, apple juice does not help meet the nutritional requirement or health benefits (25).

You can also apply apple juice or mashed flesh to your skin. Mix one tablespoon of apple juice and honey in two tablespoons of milk. Massage into your face and neck. Wash it off with warm water for supple and glowing skin.

These packs are great for removing blackheads and blemishes. They may help open the dust and oil-clogged skin pores too.

But, before you go on an apple indulgence spree, we recommend you to read the following section carefully.

Does Eating Apples Have Side Effects?

  • If you are fructose intolerant, apples may cause bloating. You may also have diarrhea, nausea, and discomfort.
  • Also, if you are allergic to plums, pears, apricots, and any Rosaceae member, you should avoid apples.
  • Apples are possibly safe for pregnant and nursing women. However, there is insufficient evidence proving this point.
  • Drug interactions with apples have also not been well-studied or characterized.

There is less research on these side effects. Hence, consult your doctor/nutritionist for a suitable dosage and the way of intake.

In Summary

Apples are among the highest consumed fruits in the world. With a balanced and power-packed phytonutritional profile, these stone fruits may boost your immunity, stamina, vision, and memory.

Ensure you eat at least one apple a day. It indeed keeps the doctor away. However, you first need to consult a health professional to understand its dosage and safety issues. You can also direct your queries, suggestions, or feedback to us.

Frequently Asked Questions

How to keep apples stored fresh for long?

For prolonged freshness, store the apples in the crisper drawer of the refrigerator. They will usually remain fresh for at least one month.
Apples continue to ripen after harvesting by releasing ethylene (a gas). Refrigeration will slow the release and ripening. You would still find trace amounts of ethylene being produced, which ripens other apples stored nearby.
Hence, store them in separate crates/trays, far from one another or any other fruit, for best results.

25 sources

Stylecraze has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.

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Swathi Handoo

Swathi holds a Master’s degree in Biotechnology and has worked in places where actual science and research happen. Blending her love for writing with science, Swathi writes for Health and Wellness and simplifies complex topics for readers from all walks of life.And on the days she doesn’t write, she learns and performs Kathak, sings Carnatic music compositions, makes plans to travel, and obsesses over cleanliness.
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