Why You Should Eat 2 Apples a Day

Apples are full of complex chemistry that feeds our body—and the helpful microbes we depend on

Eating an apple a day is good. Eating two apples a day is great. (pavla/Shutterstock)

The old saying that eating an apple a day will keep the doctor away has gained further scientific merit, as the scientific literature on this fruit garners more findings that vouch for its healthful benefits.

Eating apples is beyond folk medicine fantasy, a study found that eating one apple a day for four weeks translated to a 40 percent drop in blood levels of oxidized low-density lipoprotein/beta2-glycoprotein I complex (which may contribute to atherosclerosis) among healthy, middle-aged individuals.

Apple consumption has also been the subject of a few studies on reducing cancer risk, including liver cancer, breast cancer, and esophageal cancer. A study published in February points to apples’ ability to mediate significant gut microbial metabolic activity. All it takes: two apples a day.

Study Findings

Apples are a frequently consumed fruit and a reliable source of polyphenols and fiber, important mediators for their health-protective effects.

Validated biomarkers of food intake (BFIs) have become an important tool for assessing how well study subjects adhere to dietary guidelines. BFIs offer an accurate measure of intake, independent of the memory and sincerity of the subjects as well as of their knowledge about the consumed foods. Essentially, biomarkers let researchers see how much of an active compound a subject has consumed. BFIs solve the problems that come from asking study participants to take self-reported dietary intake questionnaires that can be affected by forgetfulness, or biased self-reporting.

New biomarkers have surfaced in recent decades from metabolic profiling studies for different foods, yet the number of comprehensively validated BFIs remains limited.

The researchers sought to identify biomarkers of long-term apple consumption, exploring how the fruit affects human plasma and urine metabolite profiles. In their randomized, controlled, crossover intervention study, they recruited 40 mildly hypercholesterolemia patients and had them consume two whole apples or a sugar and energy-matched beverage daily for eight weeks.

At the end of the trial, they found 61 urine and nine plasma metabolites that were statistically significant after comparing the whole apple intake group to the control beverage group. The metabolites included several polyphenols that could serve as BFIs.

Interestingly, the study allowed the group to explore correlations between metabolites affected by eating apples and specific fecal microbiota—specifically interactions shared by Granulicatella genus and phenyl-acetic acid metabolites. In other words, researchers could see how one nutrient affected a specific microbe living in our gut.

“The identification of polyphenol microbial metabolites suggests that apple consumption mediates significant gut microbial metabolic activity which should be further explored,” they wrote.

Gut Health Affects Your Whole Body

The link between the gut microbiota and human wellness is being increasingly recognized, where it is now well-established that healthy gut flora is a key part of your overall health. In short, the healthier the ecosystem of microbes (mainly bacteria) living in your body is, the healthier you are.

Previous studies corroborate that the richness of the human gut microbiome correlates with metabolic markers. In a study on 123 non-obese and 169 obese Danish individuals, a group of scientists found two distinct groups displaying a difference in the number of gut microbial genes and thus the richness of gut bacteria in the two groups.

Individuals with a low bacterial richness had more marked overall obesity and insulin resistance, for instance, compared with subjects who had high bacterial richness. The obese subjects among the lower bacterial richness group also tended to gain more weight over time.

A series of largely pre-clinical observations showed, too, that changes in brain-gut-microbiome communication may be involved in the pathogenesis and pathophysiology of irritable bowel syndrome, obesity, and several psychiatric and neurologic disorders.

The discovery that apples have healthy effects on the gut microbiome mean that they not only feed our body, but also feed the right kinds of bacteria our body needs.

Additional Apple Benefits

Apples are gaining a superfood and super healer status that shouldn’t be missed out on.

The benefits of this fruit include providing nutrients called carotenoids that can slow aging and help with allergies, alopecia or hair loss, diarrhea, insulin resistance, radiation-induced illness, and Staphylococcal infection. In the area of cancer treatment, apples have been found to both prevent and suppress mammary cancers in an animal model, while carotenoids extracted from the fruit have been found to inhibit drug-resistant cancer cell line proliferation.

The GreenMedInfo.com database contains 156 abstracts with apple research, scrutinizing the health benefits of apples and their related compounds.

The GMI Research Group is dedicated to investigating the most important health and environmental issues of the day. Special emphasis is placed on environmental health. Our focused and deep research explores the many ways in which the present condition of the human body directly reflects the true state of the ambient environment. This work is reproduced and distributed with the permission of GreenMedInfo LLC. Sign up for the newsletter at GreenmedInfo.health