Apples are a powerful source of antioxidants, including polyphenols, flavonoids, and vitamin C, as well as good source of fibre, and potassium. Lucky for us, there are only 47 calories in an average sized apple. The secret behind the super antioxidant capacity of the apple is its skin. The apple skin alone provides two to six times the antioxidant activity of the apple flesh alone. Therefore it's important to eat the skin as well so you obtain the full health benefits.

There are a variety of apples, and each of these have their own unique skin colour. Along with these differences in skin colour come differences in the chemical make-up of the skin itself, as the phytonutrient content varies in concentration and types of polyphenols present. For instance, in the United States, Fuji apples have the highest total phenolic and total flavonoid content of any apple. Thus, it's important to eat a variety of different apples to ensure that you maintain a healthy nutritional balance.

Along with being a tasty, low-calorie source of antioxidants, apples are also high in fibre. One large apple has 5.7 grams of fibre, which is 30 percent of the minimum amount of your daily fibre requirements. Diets that are high in fibre have been highly correlated with a reduction in the risk of developing heart disease. So, eating an apple a day not only keeps the doctor away, but also keeps your heart happy. Aside from its link to heart health, the apple has also been linked to the prevention of lung cancer, improved pulmonary (lung) function, and the prevention of type II diabetes.

Avocados

Recent research has demonstrated that avocados offer some surprising and powerful health benefits. One of the most nutrient-dense foods, avocados are high in fibre and, ounce for ounce, top the charts among all fruits for folate, potassium, vitamin E, and magnesium.

The delicious, healthy monounsaturated fat in the avocado is one of its biggest Superfood health claims. The only other fruit with a comparable amount of monounsaturated fat is the olive. The monounsaturated fat in avocados is oleic acid, which helps lower cholesterol.

One study found that after seven days on a diet that included avocados, there were significant decreases in both total and LDL cholesterol as well as an 11 percent increase in the "good" HDL cholesterol. Half a California avocado has a really excellent overall nutrient profile. At 145 calories it contains approximately 2 grams of protein, 6 grams of fibre, and 13 grams of fat, most of which (8.5 grams) is monounsaturated fat.

Avocados are also rich in magnesium. Magnesium is an essential nutrient for healthy bones, the cardiovascular system (particularly in the regulation of blood pressure and cardiac rhythms), prevention of migraines, and prevention of type II diabetes. Ounce for ounce, avocados provide more magnesium than the twenty most commonly eaten fruits, with the banana, kiwi, and strawberry in second, third, and fourth place, respectively.

They're also rich in potassium which is a critical nutrient that, until now, hasn't received the attention it deserves. Potassium helps regulate blood pressure, and an adequate intake of this mineral can help prevent circulatory diseases, including high blood pressure, stroke, and heart disease.

This fruit is also a rich source of folate. One cup of avocado contains 23 percent of the daily requirement of folate. Various studies have shown a correlation between diets high in folate and a reduced risk of cardiovascular disease and stroke.

In addition to their other heart-healthy qualities, avocados are rich in beta-sitosterol, a so-called phytosterol. Along with peanut butter, cashews, almonds, peas, and kidney beans, avocado is one of the best sources of beta-sitosterol from whole foods. A phytosterol is the plant equivalent of cholesterol in animals. Because beta-sitosterol is so similar to cholesterol, it competes for absorption with cholesterol and wins, thus lowering the amounts of cholesterol in our bloodstream. Beta-sitosterol also appears to inhibit excessive cell division, which may play a role in preventing cancer-cell growth. In both animal and laboratory studies, this phytonutrient helps reduce the risk for cancer.

Perhaps the most interesting research on avocados demonstrates that it's a powerful "nutrient booster." Avocados actually improve the body's ability to absorb nutrients from foods. It's important to remember that it's not just the presence of nutrients in foods that matter, it's also our body's ability to absorb these nutrients.