"An apple a day keeps the doctor away" is a common English-language proverb that appeared in the 19th century, advocating for the consumption of apples, and by extension, "if one eats healthful foods, one will remain in good health and will not need to see the doctor often."

Origin

A variant of the proverb, "Eat an apple on going to bed, and you'll keep the doctor from earning his bread" was recorded as a

Pembrokeshire Pembrokeshire ( ; cy, Sir Benfro ) is a county in the south-west of Wales. It is bordered by Carmarthenshire to the east, Ceredigion to the northeast, and the rest by sea. The county is home to Pembrokeshire Coast National Park. The Park ...

saying in 1866. The modern phrasing, "An apple a day keeps the doctor away", began usage at the end of the

19th century The 19th (nineteenth) century began on 1 January 1801 ( MDCCCI), and ended on 31 December 1900 ( MCM). The 19th century was the ninth century of the 2nd millennium. The 19th century was characterized by vast social upheaval. Slavery was abolish ...

, with early print examples found as early as 1887.

Scientific background

A 2013 study using computer modelling compared eating apples with taking a common daily cholesterol-lowering drug to estimate risk of

cardiovascular diseases Cardiovascular disease (CVD) is a class of diseases that involve the heart or blood vessels. CVD includes coronary artery diseases (CAD) such as angina and myocardial infarction (commonly known as a heart attack). Other CVDs include stroke, ...

. The computer model estimated that eating an apple a day was generally comparable for people over age 50 years to using a statin drug to reduce

low-density lipoprotein cholesterol Low-density lipoprotein (LDL) is one of the five major groups of lipoprotein that transport all fat molecules around the body in extracellular water. These groups, from least dense to most dense, are chylomicrons (aka ULDL by the overall densi ...

, concluding that eating an apple a day "is able to match modern medicine and is likely to have fewer side effects," while having similar annual cost. A 2015 study found apple eaters "were more likely, in the crude analysis, to keep the doctor (and prescription medications) away." When they adjusted for "sociodemographic and health-related characteristics, however, the association was no longer statistically significant”. The study also found that people who ate an apple a day used fewer

prescription medication A prescription drug (also prescription medication or prescription medicine) is a pharmaceutical drug that legally requires a medical prescription to be dispensed. In contrast, over-the-counter drugs can be obtained without a prescription. The ...

Nutritional content of an apple

A medium-size (100 gram) raw apple is 86% water and 14%

carbohydrate In organic chemistry, a carbohydrate () is a biomolecule consisting of carbon (C), hydrogen (H) and oxygen (O) atoms, usually with a hydrogen–oxygen atom ratio of 2:1 (as in water) and thus with the empirical formula (where ''m'' may or ma ...

s with negligible content of

fat In nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such compounds, most commonly those that occur in living beings or in food. The term often refers specifically to triglycerides (triple est ...

and protein, and supplies 52

calorie The calorie is a unit of energy. For historical reasons, two main definitions of "calorie" are in wide use. The large calorie, food calorie, or kilogram calorie was originally defined as the amount of heat needed to raise the temperature of o ...

s of

food energy Food energy is chemical energy that animals (including humans) derive from their food to sustain their metabolism, including their muscular activity. Most animals derive most of their energy from aerobic respiration, namely combining the carbohyd ...

. It contains a moderate amount of

dietary fiber Dietary fiber (in British English fibre) or roughage is the portion of plant-derived food that cannot be completely broken down by human digestive enzymes. Dietary fibers are diverse in chemical composition, and can be grouped generally by the ...

, but otherwise has a low level of

micronutrient Micronutrients are essential dietary elements required by organisms in varying quantities throughout life to orchestrate a range of physiological functions to maintain health. Micronutrient requirements differ between organisms; for example, hum ...

References

{{Wiktionary 1880s neologisms Apples English proverbs Health effects of food and nutrition Metaphors referring to food and drink