Antioxidant Effect for Olive Oil & Green Tea - Antioxidant Rich Foods May not be as Healthy As You Think

It has been established in scientific studies that foods rich in antioxidants are good for your health in a variety of ways. The basic idea is that antioxidants may act as quenchers of highly dangerous substances produced by the body known as free radicals. These free radicals are highly reactive and can damage many biological molecules including DNA, our genetic material. Also, by damaging proteins and other molecules, tissues start to get old and lose its ability to self-repair. Antioxidants are able to stop these free radicals and protect cells and tissues.

Green Tea: A Rich Antioxidant Food that May not be as Healthy As You Think

Green Tea is being touted as one of the healthiest foods (actually a drink) on earth. This is because of its high antioxidant content. Cathechins are credited for the antioxidant power of green tea.

However, green tea may not be as health promoting as you may think because a simple factor we sometime forget: time. Yes, the time we store the product on our shelves at home or commercially in stores and supermarkets.

In a recent study (Friedman et al, 2009), published in the prestigious Journal of Food Science, it was shown that there is a significant decrease in antioxidant power of commercially available teas if they are stored over time. A six-month storage period decreases the antioxidant power of green tea by as high as 32%. This drop in antioxidant power occurs even when moisture and temperature are controlled (such as in the study). Imagine what would happen when both moisture and temperature fluctuate such as they do in our homes.

Olive Oil: Another Rich Antioxidant Food that May not be as Healthy As You Think

Olive oil is another food that is recommended for its health-promoting properties, especially for lowering the risk for heart disease, stroke and several kinds of cancer. Olive oil is rich in phenolic compounds that act as antioxidants.

In a study (Baiano et al. 2009), published also in the Journal of Food Science, Dr. Baiano, Professor at the University of Foggia, Italy found that time decreases the antioxidant capacity of extra-virgin oil stored for six months. However, during the first 3 months of storage no significant drop in antioxidant content was observed for extra virgin olive oil.

Final Thoughts

It seems that time works against getting all the benefits that foods may offer in term of healthy bioactive compound. This has been proven at least for two very much recommended foods: green tea and olive oil. The key then is to consume these foods as soon as possible after they are processed to get all its health benefits.

Sources

Friedman et al. 2009. Stability of Green Tea Catechins in Commercial Tea Leaves during Storage for 6 Months. Journal of Food Science. 74 (2): H47 - H51

Baiano et al. 2009. Changes in Phenolic Content and Antioxidant Activity of Italian Extra-Virgin Olive Oils during Storage. Journal of Food Science. 74 (2): C177-C183