The phenomenon is one of the prime drivers of ageing and believed to play a major role in damage to arteries and cancer.
Oxygen-free radicals, or "reactive oxygen species", are natural waste products of metabolism but may be generated in greater numbers due to factors such as pollution, tobacco smoke and radiation.
One hotspot for free radicals is mitochondria, rod-like bodies in cells that act as energy powerplants.
Many "antioxidant" chemicals in vegetables and fruits such as carrots and tomatoes are known to neutralise free radicals. But according to Christopher Cortes-Rojo, who led the new research on avocado oil, they cannot reach the free radicals in mitochondria.
"The problem is that the antioxidants in those substances are unable to enter mitochondria," said Mr Cortes-Rojo, from the University Michoacana de San Nicolas de Hidalgo in Morelia, Mexico.
"So free radicals go on damaging mitochondria, causing energy production to stop and the cell to collapse and die. An analogy would be that, during an oil spill, if we cleaned only the spilled oil instead of fixing the perforation where oil is escaping, then the oil would go on spilling, and fish would die anyway."
Experiments on yeast showed that avocado oil was effective against mitochondrial free radicals. Yeast cells treated with the oil were able to survive high exposure to iron, which triggers production of huge numbers of the molecules.
"These results could be attributed to the fact that avocado oil caused accellerated respiration in mitochondria, which indicate that the use of nutrients for producing energy for cell functions remains effective even in cells attacked by free radicals," said Mr Cortes-Rojo.
The findings were presented at the annual meeting of the American Society for Biochemistry and Molecular Biology in San Diego, California.
Previous research conducted at Morelia General Hospital had shown that avocado lowers blood levels of cholesterol, and certain fats linked to diabetes.
"Our results are promising because they indicate that avocado consumption could improve the health status of diabetic and other patients through an additional mechanism to the improvement of blood lipids (fats)," said Mr Cortes-Rojo.
"We'll need to confirm that what has been observed in yeasts could occur in higher organisms, such as humans. We hope this will be the case, because there are many vital processes conserved in organisms that seem very dissimilar to humans."
"In some Mediterranean countries, low or almost no appearance of these kinds of diseases has been associated with the high olive oil consumption. Olive oil has a fat composition similar to that found in avocado oil. Therefore, avocado oil could eventually be referred to as the olive oil of the Americas," he added.
- AAP
