Olive oil is a natural, healthy fat taken from the fruit of olive trees. It has been an important ingredient of Mediterranean diets for many years, and has long been celebrated for its many health benefits.

Heart disease, diabetes, Alzheimer's and some cancers are among the illnesses that can be helped by adding olive oil to a diet, according to oliveoiltimes.com. Substituting olive oil for butter and other less- healthy fats has been credited to reverse the effects of aging.

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Beyond its dietary benefits, olive oil is also an important factor toward one's emotional well-being, including fighting depression. According to researchers from the University of Navarra and Las Palmas de Gran Canaria, a diet rich in olive oil can combat mental illness. A link was found between higher amounts of olive oil and polyunsaturated fats in fatty fish and vegetable oils and a lower risk of depression.

When combined with healthy choices from a Mediterranean diet, such as wholegrain cereals, oily fish, vegetables, and sun-dried tomatoes, olive oil is better able to work its magic, according to netdoctor.co.uk.

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"This diet, rich in vegetables and whole grains all drizzled with olive oil, can have a real impact on mental health and depression," Helen Bond, of the British Dietetic Association, told netdoctor. "Making sure the food is full of color and excitement can also add a little dynamism to your diet."

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