The olive tree is a beautiful example of Hippocrates quote “ Let food be thy medicine and medicine be thy food” The olive tree has provided food and medicine to human beings for thousands of years, the cultivation of the olive tree began over 7000 years ago. The olive tree is Native to the Mediterranean coastal areas of the eastern Mediterranean basin and coastal areas of southeastern Europe, Northern Iran, the south end of the Caspian sea, western Asia and northern Africa. The olive is a foundational food of the Mediterranean diet, especially olive oil.
The olive tree belongs to the Oleaceae family and includes 30 genera of deciduous trees and shrubs, but the olive tree (Olea Europaea) is the only one used as food and medicine.
The tree ranges in height from 3 to 12 metres and it can be a long lived tree with a general life span of 300-600 years. One of the oldest olive trees is found in Vouves in Crete and is estimated to be 2000 years old and it is still producing olives.(age not verified, it could be older)
Description of the Olive Tree
The Bark is pale grey and as the tree grows older the trunk becomes larger and more bent and twisted.
The Leaf is leathery and lance shaped, dark above with a silvery underside; each leaf is paired opposite each other on the twig.
The flowers bloom in the late spring, they are white and small and sit in loose clusters. The olive tree is a monoecious plant, meaning there are female and male flowers and pollination depends on the wind.
The Olive fruit is classed botanically as a drupe, it is a single seed with a fleshy outer layer, the colour of the skin changes as it matures from a bright green due to the accumulation of chlorophyll to pale green, straw yellow through to pink, pink purple and black. The colour changes occur due to the varying concentrations of the major pigments in the olives such as chlorophylls, carotenoids and anthocyanins
The therapeutic value of the olive tree has been documented in traditional medicine throughout the world. In traditional medicine the parts used have been the bark, leaves and fruit. Each part of the tree contains certain compounds and phytochemistry that may have benefits to human health.
The Parts Used
Leaves
Olive leaf extract may have positive protective effects on the cardiovascular system and may be of benefit in the treatment of high blood pressure, high cholesterol, and high blood sugars. Olive leaf extract may modulate oxidative stress, (oxidative stress is caused by a disturbance in the balance of free radicals and antioxidant defences) in the body and could be useful in the ageing process. The leaves are rich in polyphenols and polyphenolic compounds such as hydroxytyrosol and oleuropein; these compounds are responsible for the anti-inflammatory effects of olive leaf extract as well as the antioxidants and antimicrobial actions (only gram positive bacterial strains).
Fruit
The health benefits of the fruit (table olives) may be protective to the cardiovascular system due to its richness in monounsaturated fatty acids (MUFA) and its antioxidant capacity due to vitamin E and its role in protecting the body from oxidative damage caused by a disturbance in the balance between free radicals and the antioxidant defences. Table olives could reduce inflammation in the body as there are several phytochemicals including hydroxytyrosol (HT). Because salt is used in the fermentation of olives, people on a low salt diet may choose to use olive oil or olive leaf extract instead.
Olive oil comes from the fruit, its health benefits have been researched for decades with many epidemiological studies being done on human populations to question what health benefits does the consumption of olive oil have on human health . One such study included 60582 women in the nurses health study 1990 to 2018 and 31801 men in the health professional follow up study 1990 – 2018.
A 28 year study done on American men and women, where diet was assessed every 4 years.
This study found that higher consumption of olive oil was associated with 19% lower cardiovascular disease mortality risk, 17% lower cancer mortality risk, 29% lower neurodegenerative disease mortality risk and 18% lower respiratory disease mortality risk compared to those who never consumed olive oil.
The compounds found in olive oil may lower mortality risk by improving cardiometabolic risk factors.
The possible mechanisms include less inflammation, being less susceptible to the damage from the chemical reactions that free radicals can cause in the body (oxidation), improving oxidative stress, maintaining the health of endothelial cells lining the arteries, protecting against atherosclerotic plaque formation, reduce high blood pressure, high cholesterol and insulin insensitivity.
Olive oil is mostly made up of mono and polyunsaturated fatty acids and bioactive compounds such as vitamin E, polyphenols, polyphenolic compounds oleuropein, palmitic acids, oleic acid, hydroxytyrosol, and oleocanthal.
The health benefits of olive products depend on agriculture factors, the ripening stage and the processing methods. A good start is to use extra virgin olive oil in the diet and aim for ½ a tablespoon daily and replace the olive oil with another fat, for example margarine. You can take olive leaf as a supplement or as a herbal tea and table olives as food. You have a choice of green and black.
Olive oil is a foundational food of the Mediterranean diet. Having an eating plan that is based upon this style of eating has many health benefits including cardiovascular health and cognitive function. If you would like to start on a mediterranean diet call the office to book your time with Autumn the Naturopath.
References
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4352757/ Traditional Uses, Phytochemistry, and Pharmacology of Olea europaea (Olive)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8851878/ Consumption of Olive Oil and Risk of Total and Cause-specific Mortality Among U.S. Adults
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6150410/ Critical Review on the Significance of Olive Phytochemicals in Plant Physiology and Human Health
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7737178/ Table olives and health: a review
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5486627/ Impact of phenolic-rich olive leaf extract on blood pressure, plasma lipids and inflammatory markers: a randomised controlled trial