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An Apple a Day Keeps the Doctor Away

Malvi Bipin Savani

April 3, 2010


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In today’s society, there is a widely held belief that consuming apples will help sustain good health. But what most people may not be aware of are the realistic expectations of reaping the benefits of eating apples. The validity of the idea that eating apples actually assists in maintaining good health, especially in terms of preventing Alzheimer’s disease is due to the presence of antioxidants in apples. Fruits in general are an invaluable source of vitamins (C and A) and minerals. And these nutrients are, in turn, helpful in powering the chemical reactions in cells for survival. Moreover, the effects of essential antioxidants such as beta-carotene, and Vitamin C from fruits serve various purposes in bolstering the immune system, cognition, and other body functions (


What are antioxidants?


Antioxidants are substance that fight against the effects of free radicals and protect cells in our body from harmful substances such as tobacco smoke, and other harmful chemicals found in our body and environment ( Common examples of antioxidants found in fruits include Vitamin A and C, and beta-carotene.


Components of apples that help prevent Alzheimer’s?


Countless studies have been conducted to test the components of apples and its link to our health, and the mechanism through which it helps fight various diseases. One of the factors in apples that reduce the risk of Alzheimer’s is the fact that apples raise the levels of the neurotransmitter acetylcholine, which is correlated to improving memory. Neurotransmitters are chemicals that that are released from neurons in the nervous system to send messages to other neurons. Higher levels of acetylcholine can actually “slow the mental decline” in cognitive functions that is prevalent in individuals with Alzheimer’s (  According to a study mentioned in WebMD, normal adult mice, normal “aged” mice, and mice with the genetic programming of those with Alzheimer’s were placed on different diets to measure the level of acetylcholine. Some of the mice were placed on a poor-nutrition diet while others were placed on a normal diet. However, some of the mice in the poor-nutrition diet were given apple juice concentrate in water. The results of the study included the mice in the normal diet and those in the poor-nutrition diet with apple juice concentrate had the same levels of acetylcholine while the mice in the poor-nutrition diet only had lower acetylcholine levels (   The study reveals the fact that simply adding apple concentrate to a diet makes significant changes in the health of an animal.


On a similar note, a study published in the Journal of Alzheimer’s Disease also contributed to the importance of the neurotransmitter acetylcholine in fighting against oxidative stress and cognitive decline associate with Alzheimer’s. The study monitored the diets of normal aged mice Apples 004.JPG(9-10 months) and Alzheimer induced mice of similar age were put on either a normal diet or poor-nutrition diet that lacked folate and Vitamin E, but had iron as the pro-oxidant, and some groups received 0.5% apple juice concentrate in water (Chan A., et. al, 2006). A spectrophotometric assay of acetylcholine levels revealed that mice maintained normal acetylcholine levels in poor-nutrition diet that included apple juice concentrate. Hence, the study concluded the importance of apple juice concentrate in maintaining normal levels of acetylcholine even in the absence of a nutritious diet.


In addition, according to ScienceDaily, apples have the highest levels of the antioxidant quercetin when compared to the levels in other fruits. Quercetin has more of a “protective effect against neurotoxicity” and the presence of quercetin in the body proved to have significantly less damage to the DNA and cellular proteins than cells treated with just vitamin C ( Researchers from the Department of Food Science & Technology at Cornell University conducted a study in which isolated rat brain cells were exposed to different concentrations of either quercetin or Vitamin C. In order to simulate similar brain conditions of individuals with Alzheimer’s, the cells were exposed to hydrogen peroxide to cause cell damage similar to that found in the brains of Alzheimer patients. When the results of these cells were compared to those that did not receive any antioxidants, the cells that that received quercetin showed less cellular and DNA damage than the cells exposed to Vitamin C, and even more significantly less damage than cells exposed to neither ( Some researchers believe that quercetin works by blocking the action of free radicals, which cause the major cell damage.


Moreover, Polyphenol-rich fruits such as apples are proven to protect the body against oxidative stress that is “linked to the loss of cognitive function and Alzheimer’s” ( According to a report in the Journal of Food Sciences, when a group of genetically induced Alzheimer’s Disease (AD) mice were given fruit extracts prior to hydrogen peroxide exposure, the antioxidants protected brain tissues against oxidative damage, and even “improved cognitive performance in [these] genetically induced AD mice” (


Results from a study published in the American Journal of Medicine revealed a reasonable amount of fruit juice concentrate that would help reduce the risk of developing Alzheimer’s. The “risk for probable Alzheimer’s disease was significantly reduced” in those who consumed fruit and vegetable juices at least 3 times a week, compared to those who only drank fruit and vegetable juices less than 3 times a week (Dai Q et. al, 2006).  The study included 1836 Japanese-Americans in Washington who were “dementia-free at baseline (1992-1994)” and were followed till 2001 (Dai Q et. al, 2006). Subjects that drank polyphenol-rich juices at least three times a week showed a reduced probability of developing Alzheimer’s disease than those subjects who juices less than once per week.


Health promoting websites


Websites like “Nutri-ingredients USA” would present such information to encourage the general population to consume more healthy foods since it can have various health benefits. The websites like ScienceDaily and WebMD would present such information mainly to educate readers about the specifics of what it is in apples that help prevent Alzheimer’s and how. It also mentions experiments conducted at accredited institutions in order to prove the validity of its claims.



All fruits, in general, contain antioxidants while apples in particular contain higher levels of antioxidants quercetin, polyphenols, than most other fruits. By drinking apple juice at least 3 times a week, one can reduce the probability of being affected by Alzheimer’s. This is due to the fact these nutrients protect against oxidative stress and low levels of acetylcholine which is prevalent in neurodegenerative diseases like Alzheimer’s. A sweet, firm, and bruise-free apple is the ideal fruit for consumption (


Other than a decrease in the chance of developing Alzheimer’s disease, apples also help benefit the overall health in other ways as well. The flavanoid phloridzin that is unique to apples is important in preventing osteoporosis in post-menopausal women by strengthening bone density. Moreover, the flavanoids quercetin is also linked with the prevention of contracting various types of cancers such as breast, lung, colon, and liver cancers, as well ( Hence, the famous adage “An apple a day keeps the doctor away” in essence, is applicable to our daily lives and good health.




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MedlinePlus. (n.d.). National Library of Medicine - National Institutes of Health. Retrieved February 22, 2010, from


Thompson, L. (2010, January 14). "An apple a day keeps the doctor away" “An apple a day keeps the doctor away” » The SPA Health and Fitness . JAMSOURCE Magazine Website. Retrieved February 22, 2010, from


Vitamins and Minerals - The Body. (n.d.). The Body: The Complete HIV/AIDS Resource. Retrieved February 22, 2010, from


Warner, J. (2006, August 4). Alzheimer’s Disease, Memory and Apple Juice - WebMD. WebMD - Better information. Better health.. Retrieved February 22, 2010, from


American Chemical Society (2004, November 16). Compound In Apples May Help Fight Alzheimer's Disease. ScienceDaily.


Chan, A., Graves, V., & Shea, T. (2006). Apple juice concentrate maintains acetylcholine levels following dietary compromise . Journal of Alzheimer's Disease, 9(3), 287-291. Retrieved February 22, 2010, from


Dai, Q., Borenstein, A., Wu, Y., Jackson, J., & Larson, E. (2006). Fruit and Vegetable Juices and Alzheimer’s Disease: The Kame Project. American Journal of Medicine, 119(9), 751-759 . Retrieved February 22, 2010, from


Daniells, S. (2008, January 31). Polyphenol-rich fruit protect against Alzheimer's: study. Health food, Nutritional supplements - Energy drinks, Sport nutrition - Vitamins. Retrieved February 22, 2010, from


10 Health Benefits of Apples. (n.d.). | Health Blogs, Reviews, Articles and News. Retrieved February 22, 2010, from




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