Antioxidant is a buzz word that has been used one time too often by many food and drug manufacturing companies. Use of the word has also been shamelessly abused by some of these companies, capitalizing on consumers’ well-founded belief in its numerous health benefits. Such circumstances, no doubt, have contributed to the creation of Oxygen Radical Absorbance Capacity or ORAC, a system designed for measuring a food’s antioxidant levels.
When, Where, Who
The ORAC has its roots in the Baltimore, Maryland-based National Institute of Health, particularly a group of scientists from the National Institute on Aging. Although the creation of the ORAC comes from the NIH, there has been no official declaration proving the organization’s approval of the system.
In fact, when the US Department of Agriculture released a database of foods with its corresponding ORAC values, the list came without any official evaluation from the appropriate agencies.
How ORAC Works
In ORAC assays, a free radical generator is combined with a fluorescent molecule and resulting oxidative degradation is then measured. The free radical generator used is often an azo-initiator compound. Such initiators, when heated, create peroxyl free radicals. These substances, in return, can cause fluorescent molecules to lose their fluorescence.
Fluorescence molecules used in such tests may be a fluorescein or beta-phycoerythrin. Antioxidants coming from a certain food sample or extract are then used to prevent the free radicals from harming the fluorescent molecule. The power of the antioxidant used to protect the molecule is then measured with a fluorometer.
Benefits of Using ORAC
First and foremost, ORAC gives consumers actual figures to contemplate when comparing various antioxidant foods, products, or supplements. More importantly, the ORAC method is capable of measuring antioxidant levels while taking into account the presence or absence of lag phases with a particular sample.
Possible Drawbacks of Using ORAC
Of course, the ORAC method is not perfect. The free radicals responsible for damaging fluorescein molecules cannot be identified by the ORAC method. Secondly, the results do not give detailed explanations as to the nature of the damage inflicted by free radicals on the fluorescent molecule. Lastly, the evidence proving that free radicals are indeed the cause behind the loss of fluorescence is still inefficient. It is also important to take note that up to this day, the correlation between ORAC results and health benefits still haven’t been established.
Understanding ORAC Values
Just because a food’s ORAC value is low or high doesn’t immediately make the food possess poor or high antioxidant content. To make proper use of ORAC values, one must fully understand the various factors that could contribute to the resulting figure.
Firstly, make sure that you are comparing ORAC values based on foods or products with similar weight and form. Comparisons may be inaccurate, for instance, if you compare figures between a frozen food with a liquid product.
Water content can make a difference as well. Watermelon, for example, may seem to have low antioxidant levels but only because of its high water content.
You should also consider a food’s ORAC value per calorie. Too much consumption of an antioxidant rich food won’t do you any good if it happens to be rich in calories as well. Finally, consider the type of diet you are required to take and whether such antioxidant rich foods will be a good fit.