Cell-damaging free radicals come in several varieties—and so do antioxidants.
by Lisa James
If it isn’t a rule of biology, it should be: Nothing is ever as simple as it seems. Thinking that all cell-damaging free radicals can be stopped by one antioxidant is as old-fashioned as believing that vitamin C’s only value lies in its ability to prevent scurvy. Just as we now know that vitamin C plays a wide range of roles within the body, we have also come to realize that the presence of different free radicals requires different antioxidants to keep cells healthy.
One thing that doesn’t change: Nature always provides solutions to basic biological quandaries. In this case, the palette of colors available in fruits and vegetables provides all the antioxidants needed to help slow the clock of age.
Cells Under Attack
Free radicals are unstable molecules that damage most other kinds of molecules in the body. This starts a chain reaction that disrupts cell function, accelerating the aging process and leading to disease development. However, antioxidants can withstand this molecular onslaught and, like an extinguisher, quench the free radical “fire” before it rages out of control.
Scientists have discovered that free radicals fall into five classes: peroxyls, hydroxyls, peroxynitrites, superoxide anions and singlet oxygens. Each part of the body is subject to attack by free radicals from one or more classes. For example, the lungs are predominantly affected by peroxyls, while the heart is often targeted by free radicals from the hydroxyl, peroxynitrite and superoxide anion classes.
Antioxidants Go to Class
For a long time, Oxygen Radical Acceptance Capacity (ORAC) has been considered the antioxidant gold standard. The higher a substance’s ORAC values, the thinking goes, the better an antioxidant it must be.
Now scientists realize that antioxidants with high ORAC values, as vital as they are, fight only the peroxyl class of free radicals. This has led to testing for “Total ORAC,” or ORAC plus four additional categories: HORAC to fight hydroxyl, NORAC for peroxynitrite, SORAC for superoxide anion and SOAC for singlet oxygen.
The need for Total ORAC protection explains why it’s important to consume a range of fruits and vegetables, which contain deeply hued flavonoids. Used by plants as a defense against environmental stress, flavonoids supply antioxidants that span the entire Total ORAC range. In one investigation, total antioxidant capacity was linked to decreases in C-reactive protein, a crucial inflammation marker (Nutrition Journal 10/12). In addition, many flavonoids influence genetic activity in ways that help forestall cancer development.
Several fruits are notably rich in flavonoids. Blueberries have the highest concentration of specific antioxidant compounds, according to the Agricultural Research Service, and have been linked with better cardiovascular and brain health. Cranberries have shown to help fight inflammation besides their familiar power of protecting against urinary tract infections. Prunes contain compounds that help prevent free radical damage within the body’s fatty tissues. Bilberries, grape seeds, tart cherries, raspberries and strawberries have also demonstrated impressive antioxidant capacities. In addition to their fresh forms, these fruits are available as part of whole-food concentrate formulations.
Raising your antioxidant intake is a wise way to help keep age from catching up with you. But make sure you’re getting a full range of antioxidants to fight all free radicals, not just some of them.