by Dr. Simi Paknikar on December 23, 2011 at 11:48 AM
The unhealthy diet that is a
part of the modern urban lifestyle is one of the contributing factors to the
development of heart disease and cancer. In fact, it has been found that a
healthy diet could reduce cancers by around 30%.
Researchers have found that
a diet rich in fruits and vegetables can reduce the incidence of breast cancer,
heart disease and other ailments like cataract, diabetes, Alzheimer's disease
and asthma. The beneficial effects of
fruits and vegetables have been attributed to phytochemicals.
non-nutrient components of food and include carotenoids, flavonoids,
isoflavonoids, and phenolic acids. Phytochemicals provide a number of health
benefits. These include inhibition of proliferation of cancer cells, reduction
of inflammation and prevention of oxidation and subsequent damage to DNA,
lipids and protein components of cells. The
National Research Council recommends consuming five or more servings of fruits
and vegetables a day.
Apples are rich in phytochemicals like flavonoids and phenolic
compounds. Among the fruits consumed in the United States, apples have the
second highest level of antioxidant activity. They also have the highest amount
of free phenolic compounds compared to other fruits, which are easy to absorb
from the digestive tract.
Various studies concluded
that apples have the following health benefits:
• Apple consumption has been associated with a
reduced risk of cancer, especially lung cancer
. This appears to be the
effect of flavonoids in apples. In contrast, flavonoids from tea were not found
to be protective against lung cancer.
• Apple intake was found to reduce the risk of heart
disease, which may be associated with the presence of the flavonoids, catechin
and epicatechin in apples
. Intake of broccoli was also found to have a similar effect on the
• Apple intake was also associated with a reduction
in asthma, especially with a consumption of at least two apples a day
. Onion, tea and red wine,
which are also rich in flavonoids, failed to demonstrate the same protective
effect. Apples also appeared to improve
• Apples were also found to reduce the risk for
diabetes. In this case, quercetin, which is present in apple peels, appears to
play an important role. Apples may also contribute to weight loss.
How do apples bring about
these beneficial effects? The benefits of apples are related to their following
• Apples, especially apple peels, have good
antioxidant properties and can protect the consumer from liver and colon cancer
• The antioxidant properties of apples (due to the
presence of phenolics) also protect against lipid oxidation
. Lipid oxidation
contributes to thickening of blood vessels, a condition called atherosclerosis.
Apple peels were found to be most effective in preventing LDL oxidation,
followed by apple flesh. Apple juices showed a variable amount of inhibition,
depending on the brand.
• Apples have antiproliferative properties
i.e. they prevent the
proliferation of cancer cells. This property helps to protect against liver and
colon cancer. Here again, the peel may possess the major portion of the
• Apples have cholesterol-lowering properties
. They also raise the levels
of HDL or good cholesterol.
• In addition, apples have also been found to
inhibit the activity of cholera toxin, thus providing a beneficial effect in
Apples are very rich in
phytochemicals such as flavonoids and phenolic compounds. The apple peels are
rich in compounds like procyanidins, catechin, epicatechin, chlorogenic acid,
phlorizin, and the quercetin conjugates. The apple flesh contains catechin,
procyanidin, epicatechin, and phlorizin, though in much lesser quantities as
compared to the peels (The only exception is chlorogenic acid which is more in
the flesh than in the peels.). Quercetin conjugates are only found in the
Though apples contain a high
concentration of phytochemicals, in order to have a beneficial effect, it is
also important for these substances to be absorbed from the digestive tract.
Unfortunately, limited studies have been conducted to test this aspect.
The phytochemical content of apples varies according to the variety of
the apples. Fortunately, the phytochemical content is minimally affected by
However, it is affected by method of processing of apples into juices. For
example, apple juice obtained by pulping and straight pressing has higher
antioxidant activity compared to that obtained after pulp enzyming. Apple
pomace, the waste product accumulated from juice production, is rich in
antioxidants and may be explored for further commercial use. Same is the case
with apple peels, which are wasted during the production of apple sauce and
So, do not forget to include
apples in your next grocery list! And make sure the peels do not end up in the
1. Apple phytochemicals and their health benefits; Jeanelle et al; BMC
Nutrition Journal 2011