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Waterworld
By: Jerry Brainium
The Importance of Water During a Diet
Fat is a storage base for various toxins, and as it degrades through diet and exercise, you need to take in enough water to flush out the toxins released from stored fat. Water is also a natural diuretic, flushing out such elements as sodium, which can lead to water retention and a bloated appearance.
Bodybuilders who restrict water shortly before a contest are likely working against themselves, depending on how limited their intake is. As you restrict fluid intake, blood volume declines. When the brain detects that, the posterior pituitary gland secretes antidiuretic hormone. As the name implies, ADH works to retain water so the body can maintain the right blood volume. In other words, you wind up retaining more water when you restrict water. Conversely, drinking water inhibits ADH release. So does alcohol, which explains why you need to pee not long after you have an alcoholic drink.
People who diet often complain that they can't concentrate, but the cause may be less the lack of calories than a mild form of dehydration. Studies of animals have shown that dehydration impairs brain function. It damages the mitochondria of neurons, or brain cells'and mitochondria are the source of the energy that maintains cellular function. The level of glutamate, an amino acid that stimulates neuron activity, can increase too fast and possibly kill neurons; excess glutamate activity is a primary cause of stroke-related neuron death.
In human studies dehydrated subjects show impaired math ability, memory and reaction time.4 That happens after only a 2 percent body-fluid loss'which is considered the point where dehydration side effects appear. Nitric oxide, also produced in the brain, is involved in learning and memory. Normally dehydration increases nitric oxide in the brain, but that effect is lost in older people, which may help explain memory defects.
Studies show that drinking water with meals results in eating less food, in turn leading to weight losses. An old dieting trick is to drink a glass of water shortly before eating a meal. The water makes you feel full and decreases your appetite and food intake.
A surprising property of water is its thermogenic aspect.5 One experiment measured the effects on seven men and seven women who drank 500 milliliters, or just over a pint, of water. That amount resulted in a 30 percent increase in resting metabolic rate within 10 minutes of drinking and reached maximum effects in 30 to 40 minutes. The increased metabolic rate was fueled by fat in men and by carbs in women. This is related to a release of catecholamine hormones, such as epinephrine. The release of catecholamines usually leads to a rise in blood pressure, but not when you drink water. That's because water also elicits increased activity of the vagal nerve, which works against blood pressure increase caused by sympathetic hormones.6
Anabolic Water?
Cellular hydration is considered a potent anabolic stimulus. Conversely, when a cell is dry, catabolic effects dominate, often leading to cell death. Most studies showing the effect of cellular hydration have used cells extracted from liver. One such study showed that perfusing liver cells with the amino acid glutamine makes the size of the cell swell by 12 percent. It happens in minutes and lasts as long as the perfusion continues.
Glutamine swells cells because it promotes the entry of sodium into the cell. Inside the cell the sodium exchanges with potassium, which then exits the cell to prevent excess swelling. That mechanism is known as the sodium-potassium pump. Other substances also promote cellular hydration'various amino acids, bile acids, insulin and possibly creatine. Researchers think that most of insulin's anabolic effects come about because it promotes cellular hydration. Some substances'glucagon, cyclic AMP, serotonin and urea'promote cellular dehydration, which has catabolic consequences.
Hydration-related cellular swelling is anabolic because hydration inhibits protein breakdown. Other effects include an increase in glycogen synthesis and a decrease in glutamine synthesis, as well as uptake of lactate and amino acids. The effects of cellular hydration on isolated liver cells are replicated in muscle, bone and other cells and tissues of the body.
The effects of cellular hydration on an intact human body have been noted in clinical settings. For example, burn patients are notably dehydrated and also show huge nitrogen or protein losses. Various types of cancer marked by relative dehydration also show a high nitrogen loss. While there is a dearth of studies to back up clinical observations, one experiment did attempt to show the effect of cellular swelling in humans.7 Ten men were artificially dehydrated or hydrated. When they were hydrated, protein breakdown significantly decreased, and they showed decreased peripheral insulin sensitivity. The net effect appeared similar to that of fasting'protein sparing, increased fat oxidation, increased ketone release and impaired glucose metabolism.
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