What do environmental toxins, infections, and an unhealthy diet all have in common? Simply put, these lifestyle factors all generate oxidative stress, a harmful process in which the body’s production of free radicals exceeds its ability to counteract and detoxify their effects. Free radicals are atoms with unpaired electrons that are highly reactive; they “steal” electrons from our own DNA, lipids, and proteins, ultimately causing damage on a cellular level and impairing the body’s normal function. Over time, unrestrained oxidative stress contributes to the development of chronic diseases, including cancer, cardiovascular disease, neurodegenerative diseases, diabetes, and mitochondrial dysfunction. (1)(2)(3)(4)(5) To prevent oxidative stress from harming the body and stimulating disease processes, we need to fortify the body with antioxidants that can neutralize harmful free radicals. Hydroxytyrosol, an antioxidant found in the olive plant, has demonstrated an exceptional capacity for neutralizing free radicals and can be a powerful tool in the fight against oxidative stress and chronic disease.
What is Hydroxytyrosol?
Olive oil has long been lauded for its many health benefits. Until recently, these benefits were attributed primarily to a type of fatty acid it contains, oleic acid. However, several other foods, including pork and poultry, also contain high levels of oleic acid but do not demonstrate the exceptional health benefits of olive oil. This conundrum led researchers to wonder, could there be another bioactive compound in olive oil responsible for its outstanding health benefits? Emerging research indicates that there is indeed another bioactive compound in olive oil far more powerful than oleic acid; this compound is a small but mighty polyphenol called hydroxytyrosol.
Hydroxytyrosol emerged from humble beginnings; it was first discovered in the wastewater that resulted from olive oil processing. Hydroxytyrosol is present in all parts of the olive plant but is most concentrated in olive oil. On the ORAC (oxygen radical absorbance capacity) scale, a measure of antioxidant capacity, hydroxytyrosol has been found to surpass all other known antioxidant compounds regarding its free radical-fighting power. It boasts an astounding ORAC value of 68,576, which is 15 times higher than the ORAC value for green tea and 3 times higher than that for CoQ10. Hydroxytyrosol is a potent natural antioxidant because it is capable of donating electrons to electron-depleted free radicals, thus reducing their reactivity and preventing them from damaging DNA, lipids, and proteins. Furthermore, hydroxytyrosol promotes the expression of endogenous antioxidant enzymes, thus enhancing the body’s own defense systems against oxidative stress. (6)
In addition to its exceptional antioxidant capacity, hydroxytyrosol is also highly bioavailable compared to other antioxidant compounds. It is both fat and water-soluble, is rapidly absorbed into the bloodstream and tissues, and crosses the blood-brain barrier; this means it can access a wide variety of tissues to perform its antioxidant functions.
The Antioxidant Benefits of Hydroxytyrosol
The scientific community has taken a great interest in the free-radical fighting properties of hydroxytyrosol and numerous scientific studies have been conducted to assess its therapeutic potential. Research indicates that hydroxytyrosol may be beneficial in the prevention and treatment of several important oxidative-stress induced diseases, including cancer, cardiovascular disease, neurodegenerative diseases, diabetes, and mitochondrial dysfunction.
Epidemiological studies have found that the incidence of cancer is relatively low in the Mediterranean region compared to the United States and other European countries. This interesting effect may be attributable to the high intake of cancer-fighting, hydroxytyrosol-rich olive oil in Mediterranean countries. Hydroxytyrosol exerts anticancer activity through several different mechanisms. It reduces levels of pro-inflammatory cytokines, thus quenching the inflammation that underlies the cancer disease process. It also inhibits cell proliferation, a key characteristic of cancer, and promotes apoptosis (cell death) of leukemia tumor cells, colorectal carcinoma cells, and breast cancer cells. (7) Hydroxytyrosol also exerts anticancer activity by activating molecular signalling pathways that slow down tumor cell growth. (8)(9)
The Mediterranean diet has long been associated with cardiovascular health benefits, and the hydroxytyrosol present in olive oil, a cornerstone of the diet, may be responsible for these beneficial effects. Research has found that the antioxidant properties of hydroxytyrosol inhibit oxidation of LDL cholesterol particles; oxidized LDL is an important trigger for cardiovascular disease and inhibition of cholesterol oxidation may help prevent cardiovascular disease. Hydroxytyrosol also reduces platelet aggregation, inhibits the proliferation of smooth muscle cells, and reduces the expression of vascular adhesion molecule-1 (VCAM-1), processes that promote the formation of atherosclerotic plaques. (6)(10) Finally, animal research also indicates that hydroxytyrosol prevents cardiac cell death associated with myocardial infarctions; this finding suggests that hydroxytyrosol supplementation may be beneficial even after the cardiovascular disease process has been initiated. (11)
Oxidative stress has harmful effects on the structure and function of brain tissue and plays a role in the development of neurodegenerative diseases such as Alzheimer’s and Parkinson’s diseases. Fortunately, a growing body of research demonstrates that hydroxytyrosol can help protect the brain from oxidative damage. In vitro studies indicate that hydroxytyrosol inhibits brain cell death due to hypoxia, a lack of oxygen, and protects brain cells from oxidative stress induced by free circulating iron, a potent oxidizing compound. (12)(13) Hydroxytyrosol also prevents neuronal toxicity induced by amyloid-beta plaques and tau tangles, the protein malformations characteristic of Alzheimer’s disease. (14)(15)
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Oxidative stress promotes metabolic syndrome and Type 2 diabetes by impairing enzyme systems that regulate glucose homeostasis, by damaging insulin-producing pancreatic beta cells, and by oxidizing lipids, thus promoting widespread inflammation. In both animal and human studies, hydroxytyrosol has been found to significantly improve several key biomarkers of metabolic syndrome and Type 2 diabetes; it reverses insulin resistance, lowers triglyceride and LDL cholesterol levels, and increases beneficial HDL cholesterol. (16) Excitingly, hydroxytyrosol also lowers blood glucose to a degree equivalent to that which can be achieved with metformin, a popular pharmaceutical medication for Type 2 diabetes. This is a very impressive finding, especially considering that hydroxytyrosol is safe even at high doses and is without the side effects associated with metformin. (17)
Supports mitochondrial function
Mitochondrial dysfunction, a disorder in which cellular energy production by mitochondria is impaired, has been implicated in the pathogenesis of several chronic diseases, including chronic fatigue syndrome, neurological disorders, and obesity. Oxidative stress damages mitochondria and is, therefore, an underlying cause of mitochondrial dysfunction. Therapies that reduce oxidative stress have the potential to restore normal mitochondrial function and help those with diseases associated with mitochondrial dysfunction. The antioxidant properties of hydroxytyrosol can assist those with mitochondrial dysfunction by inhibiting oxidative damage of mitochondria, by promoting the growth of healthy new mitochondria, and by enhancing the function of pre-existing mitochondria. (18)(19)
Beyond Antioxidants: The additional health benefits of hydroxytyrosol
While hydroxytyrosol is best-known for its antioxidant properties, it has also demonstrated a handful of additional health benefits independent of its free radical-fighting effects. Hydroxytyrosol is a powerful natural antibacterial, antiviral, and antifungal agent against Salmonella, Staphylococcus aureus, the influenza virus, and Candida albicans. (20)(21) It stimulates the activity of bone-building cells, osteoblasts, and may be beneficial for people at risk for osteoporosis. (22) Hydroxytyrosol also helps to protect the liver from oxidative stress induced by a high-fat diet and prevents UV light-induced protein damage in skin cells, and may assist with skin health. (23)(24) As research continues to be conducted on hydroxytyrosol, it is likely that even more beneficial health effects of this exceptional compound will be revealed.
Supplementation with Hydroxytyrosol
While hydroxytyrosol can be found in olive oil and olive leaf products, supplementation with hydroxytyrosol can provide a more concentrated dose of this powerful nutrient. Hydroxytyrosol Extreme by ProHealth contains Olea25, a standardized hydroxytyrosol extract that delivers an extremely high antioxidant value in a convenient encapsulated form. In addition to delivering a high dose of antioxidants, which may help in the treatment of diseases associated with oxidative stress, Hydroxytyrosol Extreme may also act as a natural antimicrobial, strengthen the immune system, promote healthy liver function, support healthy bones, and promote healthy skin.
In our modern-day world, our bodies need all the support they can get in the fight against oxidative stress. Hydroxytyrosol, the most powerful antioxidant discovered to date, can be a powerful ally for combatting free radical damage. Whether you are looking to fortify your body against oxidative stress or chronic disease, hydroxytyrosol is one antioxidant you won’t want to miss!
* Lindsay Christensen is a health writer and researcher with her B.S. in Biomedical Science and an Emphasis in Nutrition. She is currently pursuing her M.S. in Human Nutrition, with the intention of becoming a Clinical Nutritionist. Lindsay’s passion for natural health and wellness has been driven by her own experience in recovering from a serious chronic illness. She blogs about chronic illness recovery and her nature-inspired approach to nutrition and healthy living on her website, Ascent to Health.
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