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.
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.
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.
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.