Copyright 2005 Internet Publications
Although creatine offers an array of benefits, most people think of it simply as a supplement that bodybuilders and other athletes use to gain strength and muscle mass. Nothing could be further from truth.
A substantial body of research has found that creatine may have a wide variety of uses. In fact, creatine is being studied as a supplement that may help with diseases affecting neuromuscular system, such as muscular dystrophy (MD).
Recent studies suggest creatine may have therapeutic applications in aging populations for wasting syndromes, muscle atrophy, fatigue, gyrate atrophy, Parkinson's disease, Huntington's disease and other brain pathologies. Several studies have shown creatine can reduce cholesterol by up to 15% and it has been used to correct certain inborn errors of metabolism, such as in people born without enzyme(s) responsible for making creatine.
Some studies have found that creatine may increase growth hormone production.
What is creatine?
Creatine is formed in human body from amino acids methionine, glycine and arginine. The average person's body contains approximately 120 grams of creatine stored as creatine phosphate. Certain foods such as beef, herring and salmon, are fairly high in creatine.
However, a person would have to eat pounds of these foods daily to equal what can be obtained in one teaspoon of powdered creatine.
Creatine is directly related to adenosine triphosphate (ATP). ATP is formed in powerhouses of cell, mitochondria. ATP is often referred to as "universal energy molecule" used by every cell in our bodies. An increase in oxidative stress coupled with a cell's inability to produce essential energy molecules such as ATP, is a hallmark of aging cell and is found in many disease states.
Key factors in maintaining health are ability to: (a) prevent mitochondrial damage to DNA caused by reactive oxygen species (ROS) and (b) prevent decline in ATP synthesis, which reduces whole body ATP levels. It would appear that maintaining antioxidant status (in particular intra-cellular glutathione) and ATP levels are essential in fighting aging process.
It is interesting to note that many of most promising anti-aging nutrients such as CoQ10, NAD, acetyl-l-carnitine and lipoic acid are all taken to maintain ability of mitochondria to produce high energy compounds such as ATP and reduce oxidative stress.
The ability of a cell to do work is directly related to its ATP status and health of mitochondria. Heart tissue, neurons in brain and other highly active tissues are very sensitive to this system. Even small changes in ATP can have profound effects on tissues' ability to function properly.
Of all nutritional supplements available to us currently, creatine appears to be most effective for maintaining or raising ATP levels.
How does creatine work?
In a nutshell, creatine works to help generate energy. When ATP loses a phosphate molecule and becomes adenosine diphosphate (ADP), it must be converted back to ATP to produce energy. Creatine is stored in human body as creatine phosphate (CP) also called phosphocreatine.
When ATP is depleted, it can be recharged by CP. That is, CP donates a phosphate molecule to ADP, making it ATP again. An increased pool of CP means faster and greater recharging of ATP, which means more work can be performed.
This is why creatine has been so successful for athletes. For short-duration explosive sports, such as sprinting, weight lifting and other anaerobic endeavors, ATP is energy system used.
To date, research has shown that ingesting creatine can increase total body pool of CP which leads to greater generation of energy for anaerobic forms of exercise, such as weight training and sprinting. Other effects of creatine may be increases in protein synthesis and increased cell hydration.
Creatine has had spotty results in affecting performance in endurance sports such as swimming, rowing and long distance running, with some studies showing no positive effects on performance in endurance athletes.
Whether or not failure of creatine to improve performance in endurance athletes was due to nature of sport or design of studies is still being debated.
Creatine can be found in form of creatine monohydrate, creatine citrate, creatine phosphate, creatine-magnesium chelate and even liquid versions.
However, vast majority of research to date showing creatine to have positive effects on pathologies, muscle mass and performance used monohydrate form. Creatine monohydrate is over 90% absorbable. What follows is a review of some of more interesting and promising research studies with creatine.
Creatine and neuromuscular diseases
One of most promising areas of research with creatine is its effect on neuromuscular diseases such as MD. One study looked at safety and efficacy of creatine monohydrate in various types of muscular dystrophies using a double blind, crossover trial.
Thirty-six patients (12 patients with facioscapulohumeral dystrophy, 10 patients with Becker dystrophy, eight patients with Duchenne dystrophy and six patients with sarcoglycan-deficient limb girdle muscular dystrophy) were randomized to receive creatine or placebo for eight weeks.
The researchers found there was a "mild but significant improvement" in muscle strength in all groups. The study also found a general improvement in patients' daily-life activities as demonstrated by improved scores in Medical Research Council scales and Neuromuscular Symptom scale. Creatine was well tolerated throughout study period, according to researchers.1
Another group of researchers fed creatine monohydrate to people with neuromuscular disease at 10 grams per day for five days, then reduced dose to 5 grams per day for five days.
The first study used 81 people and was followed by a single-blinded study of 21 people.
In both studies, body weight, handgrip, dorsiflexion and knee extensor strength were measured before and after treatment. The researchers found "Creatine administration increased all measured indices in both studies." Short-term creatine monohydrate increased high-intensity strength significantly in patients with neuromuscular disease.2
There have also been many clinical observations by physicians that creatine improves strength, functionality and symptomology of people with various diseases of neuromuscular system.
Creatine and neurological protection/brain injury
If there is one place creatine really shines, it's in protecting brain from various forms of neurological injury and stress. A growing number of studies have found that creatine can protect brain from neurotoxic agents, certain forms of injury and other insults.
Several in vitro studies found that neurons exposed to either glutamate or beta-amyloid (both highly toxic to neurons and involved in various neurological diseases) were protected when exposed to creatine.3 The researchers hypothesized that "? cells supplemented with precursor creatine make more phosphocreatine (PCr) and create larger energy reserves with consequent neuroprotection against stressors."