Invariably then, metabolism — which gives a cell its energy to live — is accompanied by ROS and similar highly reactive intermediates that damage the cell.
Most cells have built-in safeguards to counter this slow damage. One of them is to have on call a set of protector molecules that attenuate the damage, divert the extra energy, or renew the damaged molecules. Certain vitamins (C and E, to some extent A), and some special molecules help this process.
These molecules are called antioxidants. Certain enzymes go on to reduce the damaged or oxidised material back to shape, while some others capture the ROS and free radicals, and neutralise them. These are the antioxidant enzymes.
Yin and Yang
This then is the Yin and Yang of biochemistry. Metabolism or oxidation provides the energy for life, while antioxidants temper the process and protect the system from attendant damage.
It thus makes sense to boost the antioxidant capacity of the body, to help it fight oxidative stress and stay healthier longer. The approach here is qualitatively different from therapy. The fight is not against a given, sudden problem for which a short-term treatment is the answer. It is a longer haul — to build the body, fight accumulating, progressive disorder. Popping a pill or shooting a syringe is not the solution here. Tonics and health aids that supplement nutrition are the preferred mode.
And it is in this approach that antioxidants are useful as supplements. It is here that we turn to plants. Many of them pack a variety of these helpful chemicals in their leaves, bark, roots, fruits and seeds.
The most obvious-looking class of antioxidants are flavonoids and related compounds that are brightly coloured. This has led to the not-all-that-wrong notion that any plant product that is coloured is good for our health.
We know that the carotenes of carrot, lycopene of tomato, catechins of tea, resveratrol of red wine are all health promoting. Look at any health-tonic of Ayurveda — it is coloured. To this class of health aids belongs pomegranate juice, or PJ. Dr. Michael Aviram of the Rambam Medical Centre, Israel has worked on its constituents and its health benefits for several years.
Reduces cholesterol
He has shown that PJ reduces oxidative stress, reduces cholesterol and fights hardening of the arteries. He further points out that the best way to make the juice is not just from the seeds, but to crush and squeeze the entire fruit — skin and all, and using the enzyme pectinase where possible. (Both the outer and inner peels have important components, which are missed otherwise.)
Commercial pomegranate juice is thus better than the seed-crushed one. Dr. Claudio Napoli of the University of Naples, Italy working with the Nobelist Louis Ignarro of UCLA, Los Angeles has provided support to Dr. Aviram.
In a recent paper in PNAS (March 29, 2005), he shows that PJ modulates several oxidation-sensitive genes. These are important steps that govern atherosclerosis and thus, heart disease.
Physiological effects
While Aviram's work shows the physiological effects on experimental animals and volunteer humans, the Napoli paper provides the gene-controlled biochemical steps involved in the protection mechanisms.
PJ, with its 40 per cent flavonoid content, is a thus multi-level tonic, warding off many bad effects of oxidative stress.
While research so far has shown its beneficial effects against heart disease, chances are it might be good against arthritis, eye diseases such as cataract and age-related macular dystrophy, and Alzheimer's and senile dementia as well. It might yet have an edge over tea on this score.
But what should the daily dose be? While the American Health Foundation recommends 6-10 cups of tea a day, Aviram gave 50-80 ml of PJ per day to his human volunteers. That is about half a cup a day. Go for it!
dbala@lvpei.org
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