The health-improving qualities of foods such as olive oil, nuts and fruit can interact with other medications, causing more harm than good, The Wall Street Journal reported.

Newer research conducted in the U.S. suggests that fruit juices, including cranberry and pomegranate, as well as olive oil may also interfere with how anti-cholesterol drugs known as statins work in the body.

Other laboratory studies show that certain popular teas can block the effect of some medications, including the flu drug Tamiflu. And switching to a low-fat diet, itself a healthy lifestyle change, could reduce the potency of some medications.

Diet can interact with medicine in two main ways. Some foods block the body's ability to absorb certain medications, effectively reducing the dose a person receives. Other foods enhance the absorption of some drugs, which can lead to a possible overdose.

In general, diet will only interact with medications when a person is consuming exceptionally large portions of certain foods, pharmacology and medical experts say. A few teaspoons of olive oil on pasta typically does not pose any problems, for instance.

"For every drug there is, there are unintended side effects. You should expect the same thing when taking nutrients at drug levels," said Patrick Stover, director of the division of nutritional sciences at New York's Cornell University.