Nutritional metrics for deciphering your dinner plate and maybe even stopping the clock

Dr. Lerner

Oxygen radical absorbance capacity (ORAC) has emerged as a standard of measure of the antioxidant levels of specific compounds within blood products.¹ This measure has become more widely accepted because it combines both the percentage of free radical inhibition and the length of inhibition of various compounds such as teas, fruits, vegetables and animal tissues. Numerical ORAC values now exist for varying foods, but what is their relevance for us and for our patients?

Aerobic cellular respiration (essential to life) produces free radicals, the most common of which in humans is the peroxyl radical, but also includes hydroxyl, superoxide and reactive nitrogen radical species. Environmental factors such as tobacco smoke and radiation exposure also increase the prevalence of free radicals in the body. A free radical (NOT a hippie out on bail!) represents a molecule with an incomplete electron shell which makes it more chemically reactive. These "charged" oxidants attempt to remove electrons from other molecules, resulting in damage to DNA, proteins, lipids and other compounds which, in turn, produce mutations or alterations in the function and genetic makeup of cells.

Living organisms have developed complex antioxidant systems to counteract these damaging free radicals which accumulate over time. Damaged DNA is repaired by enzymes that excise the oxidative radicals which are then excreted in the urine. But not all of the free radicals are removed. In addition to these endogenous systems of enzymatic antioxidant activity, consumption of dietary antioxidants has proven to be of great value in reducing free radicals and thus lowering the incidence of cardiovascular disease, stroke and certain cancers. Some exogenous antioxidants contained in foods include Vitamins A, C and E, and minerals such as selenium.

As we continue to learn about the impact of free radicals on the aging process and disease, our understanding of antioxidants has also expanded, not only as to how they function, but also their potential sources. Scientific publications abound on the antioxidant effects of varying foods. Nuts and fruits, spices and oils — and the list continues.^2,3 A study published in 2003⁴ analyzed several apple species and compared not only their antioxidant activity, but also peeled versus whole! Its results showed that the peel contained the highest antioxidant value and argued that, in processing apples into applesauce, the peel is discarded and millions of pounds of vital nutrients are thrown out each year. As you read that study, you might think, "Don't these people have anything else to do? People are dying like flies and these guys are peeling apples?" Yet, here we are reveling in the beauty of this work because it helps us understand not only the benefit of various foods, but the importance of where they came from, and how and in what form they arrive at our dinner tables.