It’s a scientific message of great urgency: One of the best things you can do for your brain is eat antioxidants. Antioxidants are universally recognized as the saviors of cells at all ages and under virtually all circumstances of health or disease. Antioxidants are chemicals that neutralize other hazardous chemicals called oxygen-free radicals that perpetually attack and damage bodily cells, disrupting their functioning and promoting aging and diseases of all kinds.
Scientists increasingly recognize that many mental problems from conception to death stem from too many rampaging free radicals and not enough antioxidants. In short, hordes of oxygen free radical thugs can get out of control, corrupting cells’ genetic DNA, ripping their membranes, eroding their normal functioning, and sometimes destroying them. If you have a strong internal police force of antioxidants on patrol, the extent of the free radical damage to cells is limited.
You cannot avoid free radicals altogether. They are normal, in fact are generated when you breathe, or burn calories and glucose during normal metabolism. They also get in your body through cigarette smoke, air pollution, and toxic chemicals in the air and water. They also are carried into cells in foods, notably fatty foods. Under certain circumstances, they are good guys. For example, free radicals help destroy invading bacteria and viruses. But in general, they are the dark forces that attack fatty cell membranes and genetic material (DNA), creating permanent cellular damage that accumulates over time, leading to accelerated aging and virtually every chronic disease imaginable, including heart disease, cancer, diabetes, arthritis, and degenerative brain problems.
Thus, all your organs and tissues are subject to free radical assaults. But the brain appears to suffer most of all.
No question, free radicals are your brain’s most malicious enemies. Your brain is the most vulnerable target of free radicals, say experts. One reason is that the brain generates more free radicals than other bodily tissue, because it uses so much oxygen and is the fattiest organ in the body. Fat is the favorite breeding ground for free radicals. Oxygen reacts with fat molecules in ways that generate free radicals—a process called oxidation—which leaves the fat oxidized or, in a word, rancid.
A rancid brain is not a well-functioning brain. Indeed, the process in which the fat in brain cell membranes becomes oxidized, or rancid, occurs in many neurodegenerative conditions, such as Alzheimer’s and Parkinson’s. Rancid fat in brain cell membranes causes incredible havoc, screwing up release and uptake of neurotransmitters and transport of all-important glucose. Worse, oxidized fat cripples the functions of mitochondria (energy factories of cells), prompting a cas cade of events that can cause cell death. The brain is also rich in iron, which sparks the formation of free radicals and fat oxidation.
How Free Radicals Destroy Your Brain
To keep the body alive, nature, in its evolutionary wisdom, devised a kind of SWAT team or antioxidant defense system to extinguish and dispose of the dangerous free radicals. Now, if you don’t disarm these molecules, they entice certain cells in your body to actually self-destruct or commit suicide, a process called apoptosis; researchers believe that’s what happens to destroy brain cells diseased with Alzheimer’s.
“Your brain is particularly vulnerable to free radical damage for two reasons. First, it is a hotbed of activity; it never stops working. Brain cells need a constant flow of blood and oxygen to produce energy, which increases the production of free radicals. Second, the brain is composed of 50 percent fat, which makes it vulnerable to lipid peroxidation.” —Dr. Lester Packer, University of California, Berkeley
If you think of free radicals as thugs assaulting the cells of your brain and body, you can visualize the antioxidants as the body’s ever-vigilant police force that searches out and destroys free radicals and attempts to repair their damage. Antioxidants vary in their ability to combat free radicals, but the stronger and more efficient they are, the greater their so-called “antioxidant capacity.”
Generally, antioxidants do an admirable job, depending on their magnitude and efficiency. According to leading authority Bruce. Ames, of the University of California at Berkeley, the DNA of a single cell takes about ten thousand
free radical hits per day. That’s one cell. If you multiply that by trillions of cells, you can begin to visualize the potential extent of bodily devastation. However, antioxidants manage to repair at least 99 percent of the free radical damage to cells. Still, the tiny fraction of cellular damage that is not repaired accumulates over the years and eventually can cripple and destroy cells and shut down whole organs.
Such cumulative damage from free radicals is a primary cause of premature aging, and age-related chronic diseases and disorders. Nowhere is the damage more tragic to the personality and intellect than in the brain. Of all major organs, at least in lab animals, the brain contains the lowest “antioxidant capacity,” according to brain tissue analyses by Tufts University researchers. That is why it is all-important to maintain a highly efficient, functioning antioxidant defense system and to feed your brain a steady supply of antioxidants.
BOTTOM LINE: Your brain is the number one target of destructive “free radical” chemicals that rampage through your body, damaging cells and inducing premature aging, brain dysfunction, and virtually all other chronic diseases.
The brain may be particularly vulnerable to the damaging effects of free radicals because it is relatively deficient in antioxidants to begin with.” —James Joseph, Ph.D., chief of neuroscience at the U.S. Department of Agriculture Human Nutrition Research Center on Aging at Tufts University
Deadly Imbalance
Every instant of your existence is an elegant dance of life and death between free radicals and antioxidants. When free radical activity gets the upper hand over antioxidant activity, the result is an imbalance known in scientific jargon as “oxidative stress.” This means the free radical thugs can overpower the antioxidant police and beat up on your cells, causing their membranes to leak, their neuronal connections or dendrites and synapses to shrink, their energy to be depleted, possibly ending in cell death. It’s critical to keep the right amounts of the right combination of antioxidants in your body and particularly in your brain.
If free radicals predominate, your brain is headed for trouble. If antioxidants predominate, your brain is apt to stay in good shape. Unfortunately, as you age, your body tends to produce more free radicals and fewer antioxidants, slowly tipping the scales toward mental and physical decline. This antioxidant production slowdown begins around age twenty-five. That’s why it is especially imperative to take in more antioxidants as you get older, to try to maintain a more youthful balance.
IF YOUR BRAIN GOES RANCIDThe first step in the destruction of a nerve cell is often a process called “lipid peroxidation.” It’s the same event that turns LDL cholesterol particles toxic so they can infiltrate blood vessel walls, leading to a buildup of plaque and clogged arteries. It happens when unstable renegade “oxygen free radical” chemicals attack unsaturated fatty molecules in a cell’s membranes. During the hit, the attackers leave the fat spoiled and rancid, crippling the cell so it can no longer properly move calcium out of the cell and glucose into the cell.
Calcium can rise to toxic levels, initiating a cascade of events that activates poisonous glutamate and generates more free radicals as well as arachidonic acid, a nerve poison. It ends when the cell’s command center, the mitochondria, dispatches “suicide proteins” and signals enzymes to depolarize inner membranes. In a fit of self-destruction, the cell’s DNA disintegrates and it shrinks into oblivion. Another brain cell vanishes, and if enough are destroyed, the brain grows weaker and dysfunctional.
What’s important about this process—which happens during normal aging as well as in degenerative brain diseases—is that you can stifle the initiating event, the lipid peroxidation of the cell’s membrane, by getting specific fat-active antioxidants into your brain. Best at combating this lipid peroxidation of brain cells: vitamin E, lipoic acid, coenzyme Q10, flavonoids in fruits and vegetables. Also critical is glutathione, made internally by the body. But don’t take glutathione supplements; they may encourage lipid peroxidation. Best way to raise glutathione in nerve cells: Take lipoic acid and vitamin C.
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