An apple a day could really keep the doctor away — by reducing your risk for heart disease, cancer, and possibly even Alzheimer’s disease, recent studies suggest. What’s more, this delightfully crunchy fruit also supports gut health, with a new report describing apples as “the best probiotics,” with a more diverse range of “good” bacteria than any dietary supplement on the market.

Indeed, apples have so many documented health benefits that researchers at Florida State University have dubbed them a “miracle fruit” and Medical News Today recently ranked them No. 1 in a recent list of the top ten healthy foods. What makes apples such a nutritional powerhouse? Here are some intriguing discoveries about the world’s most popular fruit, plus key takeaways from the BaleDoneen Method.

Apples contribute to a healthy gut microbiome — and arterial wellness.

One of the newest — and most surprising — discoveries about apples is that they are a rich source of probiotics: bacteria that enhance gut and heart health. A new study published in Frontiers in Microbiology found that an average apple contains about 100 million bacteria, almost all of which are either harmless or beneficial. And unlike probiotic supplements, which usually contain only a few types of bacteria, apples have a multitude of different microbes. Most of their probiotics are found inside the apple, rather than on the peel, with the highest concentration in the core. The study did not find any significant difference in the bacteria counts of organic and conventionally grown apples, but the organic apples had 40% greater diversity of bacteria, which could contribute to favorable health effects, the study concluded.

BaleDoneen takeaway: The relationship between the gut microbiome (the trillions of microbes living inside our GI tracts) and arterial health is one of the hottest areas of scientific research. What we eat plays a key role in the composition of our gut microbiome — and the substances it generates (metabolites). For example, when people eat choline (found in red meat, egg yolks and dairy products), gut bacteria break it down to a metabolite called trimethylamine (TMA), which the liver converts to trimethylene N-oxide (TMAO). Studies have linked high levels of TMAO to increased risk for heart attacks, strokes and death from CV causes. Conversely, certain bacteria found in probiotic foods (such as apples, yogurt and fermented foods like kimchi) and supplements have been linked to improved levels of cholesterol, inflammation, and blood pressure. As a BaleDoneen study recently reported, probiotics may also be beneficial to people with diabetes who carry a certain variant of the haptoglobin gene. Always check with your medical provider before taking any supplement to make sure it’s appropriate for you. 

Flavonoid-rich foods, such as apples, cut risk for cardiovascular disease (CVD) and cancer.

In a new study of more than 56,000 people who were tracked for 23 years, those who consumed about 500 mg of flavonoids in their diet daily were less likely to die from CVD, cancer or other causes than those who ate lower amounts. Flavonoids are found in many plant foods, such as fruits, vegetables, tea, dark chocolate and red wine. Consuming 500 mg a day is easy, the study’s lead author, Nicola Bondonno, PhD, told Healthline: “One cup of tea, one apple, one orange, 100 grams of blueberries, and 100 grams of broccoli would provide a wide range of flavonoid compounds and over 500 mg of total flavonoids.” The research was published in Nature Communications.

BaleDoneen takeaway: Eating more fruits and veggies is one of the easiest — and tastiest — ways to add years to your life. For example, another recent study estimated that worldwide, 7.8 million people die prematurely each year due to low intake of fruit and vegetables, defined as eating less than 800 grams (28.3 ounces) a day. One of the best ways to add more produce to your diet — and keep your weight in the healthy range — is to fill half your plate at each meal with fruits and vegetables. For a heart-healthy lunch on the go, try our Must-Have Kale Salad recipe or our other salad-in-a-jar recipes.

Apples reduce risk for stroke and may protect memory.

A recent analysis pooling the results of 20 studies with a total of 760,629 participants found that for each additional serving of produce that people ate daily, their risk for stroke fell by 11%. The investigators reported that apples, pears, citrus fruits and leafy green vegetables may account for this protection. Another study of nearly 10,000 people found that those who ate the most apples over 28-year period had the lowest risk for stroke, compared to those who ate the fewest apples. There is also preliminary evidence from animal studies linking apples and their juice to improvements in memory and reductions in the brain’s levels of beta-amyloid protein (a protein that builds up in the brains of people with Alzheimer’s disease). However, research in humans is needed to investigate if a diet that includes apples has any effect on our memory or risk for Alzheimer’s.

BaleDoneen takeaway: The link between a plant-based diet and reduced risk for heart attack and stroke is now well-established in large studies. Emerging evidence suggests that flavonoids have many beneficial effects, including improving blood pressure, inflammation, cholesterol and arterial health, all of which help explain why eating food rich in these compounds, such as produce, helps protect arterial and brain health. To learn about other strategies for stroke prevention, check out our blog posts, “The No. 1 Risk for Stroke—and What to Do About It, ” “The Surprising Stroke Risk that Affects 50% of Americans Over Age 30,” and “5 Healthy Lifestyle Steps that Lower Stroke Risk 90%.” To find out what you can do to ward off memory loss, read, “10 Lifestyle Moves That Could Lower Your Dementia Risk by 35 Percent.”