October 14, 2022 9 min read
Packed with antioxidants, vitamins, and fiber, the skin of an apple has numerous health benefits, particularly for your skin.
Have you ever heard the phrase, “an apple a day keeps the doctor away?”
Join us on a voyage of discovery as we tell you why there is quite a bit of truth in this age-old adage.
Although for many people, the fleshy inner section of an apple is the most appealing and arguably tastiest part, the outer skin contains some powerful antioxidants and nutrients that have well-known health benefits.
There is plenty of research available to demonstrate that a diet rich in fruit and vegetables can decrease the risk of chronic disease[i]. The main reason for this is that plant-based foods are rich in phytochemicals – natural plant compounds – including polyphenols, flavonoids and carotenoids[ii].
Apples are a particularly abundant source of phytochemicals, are a popular food choice across the world and have been linked to lower incidences of some cancers, heart disease, asthma, and diabetes.
Apples actually contain over 60 different phenolic compounds and the peel itself contains a higher level of polyphenols than the flesh or core[iii]. The consumption of apples has been associated with a reduced risk of cardiovascular disease, and it has been suggested that this is because of the high levels of polyphenols the fruit contains. A study involving mice by Tian et al. (2017) compared the effects of apple peels and apple fleshes on some cardiovascular parameters, including blood pressure, insulin resistance, and lipid metabolism. It concluded that apple polyphenols, especially those present in apple peel, have important cardioprotective effects[iv].
In future, think twice before throwing your apple peel away because you could also be throwing away an abundant supply of:
Let’s delve a little deeper into the health benefits of apple skin.
Because fruit, vegetables, and other plant foods are notoriously high in antioxidants, consuming a diet rich in these foods could help to lower oxidative stress in your body. Oxidative stress occurs when there is an imbalance between free radicals and antioxidants. Free radicals are highly reactive because they have an uneven number of electrons, making them imbalanced. So, they hunt around the body for a donor to even themselves up. Antioxidants, on the other hand, are able to donate an electron to a free radical to help balance them without destabilising themselves.
However, if the activity of free radicals and antioxidants is out of kilter, it can lead to oxidative stress. If there is an increase in free radicals, it can cause damage to the DNA, proteins, and fatty tissue in your body, resulting in inflammation, and leading to a wide range of chronic diseases, including:
Therefore, foods such as apples and their peel could play a critical role in keeping oxidative stress at bay by promoting good health.
There have been several studies conducted assessing the benefits of apples on heart health. According to Shehzadi et al. (2020), the anthocyanins and quercetin present in apple peel can have blood pressure-reducing effects[vii]. Another study by Larson et al. (2012) concluded that quercetin in stage 1 hypertensive men was able to reduce blood pressure independent of other factors, including angiotensin-converting enzyme (ACE) activity[viii].
A Finnish study was conducted in 1996, consisting of a cohort of 5133 men and women who were heart disease free and aged between 30 and 69 years old. The study analysed the association between dietary flavonoids and coronary mortality. The results showed that an increase in flavonoid intake reduced the occurrence of coronary mortality in women but not in men[ix].
Data collected from the same cohort also found that the consumption of apples was linked to a lower risk of thrombotic stroke (the type caused by a blood clot)[x]. The compound quercetin, which is associated with many of these heart health benefits, is found almost exclusively in the peel of apples. In fact, Eberhardt et al., (2000) concluded that apples with their peel removed had less antioxidant activity than those with their skin intact[xi].
Asthma is a common lung condition that affects more than 300 million people worldwide[xii]. However, there is some research that eating apples is associated with a lower risk of asthmaii. A study conducted in 2015 by Shaheen et al. found an association between eating apples and a reduced risk of asthma. The study also found a similar association between the condition and red wine consumption, which is also rich in flavonoids[xiii]. Therefore, flavonoids could have a protective effect against asthma.
Cancer is the leading cause of death worldwide and so looking for ways to help prevent it is crucial. According to a study conducted by researchers at Cornell University in 2007, apple peel contains some potent compounds that can inhibit or kill cancer cells in the lab[xiv].
The study found that these compounds, called triterpenoids had antiproliferative effects against cancer cells in the liver, colon and breast. Apples have been shown to have the third highest antiproliferative activity compared to 11 other commonly eaten fruits behind cranberries and lemons[xv].
Apples are the most consumed fruit in temperate climate countries. They contain many different polyphenols, but those found in apple peel extract are believed to have anti-diabetic properties[xvi].
In animal models, apple peel extract has shown potential for use as a therapeutic intervention for managing diabetic peripheral neuropathy (nerve damage). Another debilitating side effect of diabetes is impaired wound healing. Moreover, the same study found that applying a topical hydrocolloid film containing between 5 and 20% apple peel extract to diabetic wounds significantly reduced the surface area of the wound[xvii].
A 2002 Finnish study also found that an increase in quercetin intake (a flavonoid found in apple peel) is associated with a reduction in type 2 diabetes risk[xviii]
At Layer Origin Nutrition, we love all things to do with the gut. So, it’s probably no surprise to hear that apples – including their peel – can have great effects on your gut microbiome.
In a 2019 study published in Frontiers in Microbiology,researchers found that apples contain 1755 different types of bacteria, equating to a whopping 100 million bacteria living in and around an apple. Before you put yourself off of apples for life, it’s important to note that the bacteria found in apples can help to keep your own gut microbiota diverse and healthy[xix]. In fact, many of the strains found in apples were probiotics like Lactobacillus and members of the Firmicutes genera,so help to support gut health.
As well as containing a huge amount of health-promoting bacteria, apples are also packed with both soluble and insoluble fibre. Apples contain a type of soluble fibre called pectin which can be used as an energy source by your gut microbes. The bacteria in your gut break down the pectin found in apples (and other sources) and transform it into short-chain fatty acids (SCFAs) such as acetate, propionate, and butyrate, all of which have been shown to have numerous health benefits[xx].
That’s not all. The insoluble fibre found in apples is also great for your digestive system. That’s because it helps to keep things moving through your gastrointestinal tract by providing bulk, drawing water to your stools to make them easier to pass, and helping food to move through the tract quickly[xxi].
Top Tip:try to avoid apples (and other insoluble fibre sources) immediately before exercise, such as a run, as this can cause stomach cramps and affect your performance.
When it comes to apple peel powder, the clue really is in the name. It’s just a powdered form of apple peel – the outer skin of one of the world’s most popular fruits[xxii].
Hidden inside the skin of an apple is an array of natural chemicals called phytonutrients, including vitamins and antioxidants that can have some exceptional health benefits. In fact, eating an apple with the peel on contains 50% more phytonutrients than a peeled apple!
However, if you’re the type of person who just can’t stand eating the edible skin of some fruit and veg, then Layer Origin has the perfect solution for you – our Organic Apple Peel Powder. Our pure, organic formulation is the perfect way to ensure you’re getting all of the benefits of eating the skin of your apple. Plus, even if you don’t mind munching the entire fruit, our Apple Peel Powder is a great way to keep your health in tip-top condition.
The evidence is clear – an apple a day really might keep the doctor away! Apples, including their peel, appear to play a key role in reducing your risk of developing chronic disease and helping you to maintain a healthy lifestyle.
Apple peel is packed full of phytonutrients that work hard to keep your body in top condition. Research has highlighted anti-cancer, anti-diabetes, and anti-heart disease effects as well as benefits for your gut and beyond.
Remember, to get the maximum benefit from your apple, you need to eat the skin too! If you want a head start, then don’t forget to order our Apple Peel Powder today – it’s packed full of nutrients, and just two scoops are equivalent to the peel from 2 medium-sized apples or 3 small-sized apples!
Written By: Leanne Edermaniger, a science writer who enjoys writing about all things related to the gut microbiome.
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[iii] Sun J, Prasad K, Ismail A. Polyphenols. Nova Scotia: Nova Science Publishers; 2013. p. 332-361.
[iv] Tian J, Wu X, Zhang M, Zhou Z, Liu Y. Comparative study on the effects of apple peel polyphenols and apple flesh polyphenols on cardiovascular risk factors in mice. Clinical and Experimental Hypertension. 2017;40(1):65-72.
[v] Apples, raw, with skin (Includes foods for USDA's Food Distribution Program) [Internet]. US Department of Agriculture. 2019 [cited 2022 Oct 11]. Available from: https://fdc.nal.usda.gov/fdc-app.html#/food-details/171688/nutrients
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[vii] Shehzadi K, Rubab Q, Asad L, Ishfaq M, Shafique B, Ranjha M, Mahmood S, Mueen-Ud-Din G, Javaid T, Sabtain B, Farooq R. A Critical Review on Presence of Polyphenols in Commercial Varieties of Apple Peel, their Extraction and Health Benefits. Open Access Journal of Biogeneric Science and Research. 2020;6(2).
[viii] Larson A, Witman M, Guo Y, Ives S, Richardson R, Bruno R, Jalili T, Symons J. Acute, quercetin-induced reductions in blood pressure in hypertensive individuals are not secondary to lower plasma angiotensin-converting enzyme activity or endothelin-1: nitric oxide. Nutrition Research. 2012;32(8):557-564.
[ix] Knekt P, Jarvinen R, Reunanen A, Maatela J. Flavonoid intake and coronary mortality in Finland: a cohort study. BMJ. 1996 Feb 24;312(7029):478-81. doi: 10.1136/bmj.312.7029.478. PMID: 8597679; PMCID: PMC2349921.
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[xii] Prevalence | Background information | Asthma | CKS | NICE [Internet]. Cks.nice.org.uk. 2022 [cited 2022 Oct 11]. Available from: https://cks.nice.org.uk/topics/asthma/background-information/prevalence/#:~:text=Risk%20factors-,What%20is%20the%20prevalence%20of%20asthma%3F,aged%206%20to%207%20years.
[xiii] Shaheen SO, Sterne JA, Thompson RL, Songhurst CE, Margetts BM, Burney PG. Dietary antioxidants and asthma in adults: population-based case-control study. Am J Respir Crit Care Med. 2001 Nov 15;164(10 Pt 1):1823-8. doi: 10.1164/ajrccm.164.10.2104061. PMID: 11734430.
[xiv] An Apple Peel A Day Might Keep Cancer at Bay [Internet]. ScienceDaily. 2007 [cited 2022 Oct 11]. Available from: https://www.sciencedaily.com/releases/2007/06/070601181005.htm#:~:text=An%20apple%20a%20day%20keeps,cancer%20cells%20in%20laboratory%20cultures.
[xv] Sun J, Chu YF, Wu X, Liu RH. Antioxidant and antiproliferative activities of common fruits. J Agric Food Chem. 2002 Dec 4;50(25):7449-54. doi: 10.1021/jf0207530. PMID: 12452674.
[xvi] Kamdi SP, Raval A, Nakhate KT. Effect of apple peel extract on diabetes-induced peripheral neuropathy and wound injury. J Diabetes Metab Disord. 2021 Feb 3;20(1):119-130. doi: 10.1007/s40200-020-00719-6. PMID: 34222062; PMCID: PMC8212242.
[xvii] Kamdi SP, Raval A, Nakhate KT. Effect of apple peel extract on diabetes-induced peripheral neuropathy and wound injury. J Diabetes Metab Disord. 2021 Feb 3;20(1):119-130. doi: 10.1007/s40200-020-00719-6. PMID: 34222062; PMCID: PMC8212242.
[xviii] Knekt P, Kumpulainen J, Järvinen R, Rissanen H, Heliövaara M, Reunanen A, Hakulinen T, Aromaa A. Flavonoid intake and risk of chronic diseases. Am J Clin Nutr. 2002 Sep;76(3):560-8. doi: 10.1093/ajcn/76.3.560. PMID: 12198000.
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[xx] Blanco-Pérez F, Steigerwald H, Schülke S, Vieths S, Toda M, Scheurer S. The Dietary Fiber Pectin: Health Benefits and Potential for the Treatment of Allergies by Modulation of Gut Microbiota. Current Allergy and Asthma Reports. 2021;21(10).
[xxi] Fiber [Internet]. The Nutrition Source. 2022 [cited 2022 Oct 11]. Available from: https://www.hsph.harvard.edu/nutritionsource/carbohydrates/fiber/
[xxii] Top 15 Most Popular Fruits in The World - The Science Agriculture [Internet]. The Science Agriculture. 2022 [cited 2022 Oct 9]. Available from: https://scienceagri.com/top-15-most-popular-fruits-in-the-world/
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