March 10, 2001
Creatine: user-friendly or buyer beware?
Josh Peterson, a 20-year-old college student from Chippewa Falls, is now in his third year at UW-Eau Claire, a double major in MIS and accounting with several minors tacked on as well. Peterson’s off-campus bedroom exhibits one of his primary non-academic interests: sports. The walls are plastered with basketball posters, including a life-size Michael Jordan, while the television spouts the latest sports scores from ESPN.
“I love to play basketball and I started playing in a league again,” Peterson said of his intramural team, made up of his Phi Gamma Delta social fraternity brothers and other friends.
Like many of his friends, Peterson exercises regularly to stay in shape. He estimates that he lifts weights and plays basketball about four days per week. Unlike some of his friends, though, Peterson takes creatine to enhance the results he gets from the exercise.
Is this an unusual practice? It appears to be growing in popularity, actually. Creatine use has soared in the last five years or so. According to research done by Jude Sullivan and Tim McGuine of the UW Health Sports Medicine Center in Madison, the estimated consumption of creatine in 1999 exceeded 2.5 million kilograms, or 2.5 thousand metric tons! In 1997, supplement industry reports indicated that the market value of all dietary supplements to the public at large was $11.8 billion. Of that, sales for creatine made up $200 million.
The spectrum of creatine users is not limited to young college students like Peterson. High school athletes, college professors, fitness trainers, professional athletes and others have also reported using the supplement.
Despite its soaring popularity, creatine remains a controversial supplement. While the creatine users interviewed for this story said they had few side effects and most would recommend it to others, the medical professionals questioned remain skeptical about its use and its long-term effects. Considered a dietary supplement, creatine is not subject to regulation by the Food and Drug Administration (FDA). Thus its benefits, side effects, and long-term safety have been left up to researchers, manufacturers, and the average citizen to determine.
What is creatine?
Creatine, or creatine monohydrate, is a natural substance formed by combining three amino acids (the building blocks of protein) and used by the body for energy production. It is produced mainly in the liver, pancreas, and kidneys. Ninety-five to 98 percent of the creatine is then transported to the body’s muscle cells. Since the body makes its own creatine (approximately 1 to 2 grams per day) it is not considered an “essential” nutrient. This naturally-produced creatine accounts for one-half of the body’s daily requirement, according to “A primer on creatine supplementation,” an informational packet for high school educators put together by the UW Health Sports Medicine Center. The other half (about 1 gram on average) of the daily requirement is satisfied through dietary sources like meat and fish, according to an article in the Canadian Journal of Applied Physiology.
Why are people taking creatine?
Motivation for using creatine ranges widely depending on an individual’s interests and physical fitness level, but most take it to have a more toned, muscular appearance or to help them with anaerobic exercises like weightlifting.
McGuine, a certified athletic trainer, conducted a study, “The prevalence of creatine supplementation in high school athletes,” in collaboration with Sullivan, an exercise physiologist. The study, conducted from October 1999 through March 2000, consisted of an anonymous survey of approximately 4,000 Wisconsin high school athletes of both sexes. Twenty-five percent of boys and 3.5 percent of girls surveyed in the study had used creatine. The main motivation for both males and females was gaining strength.
McGuine said one common misconception high school students had about creatine was its effect on weight.
“Some boys in our study were taking it to gain weight, while girls were taking it to lose weight,” he said. “The weight gain may not be added as lean muscle; it could be fat or retained water.”
At the high school level, McGuine said people use creatine as a result of peer influence.
“It’s a lot like drugs and alcohol in regards to peer pressure,” McGuine said. “They get a lot of encouragement to use creatine from their peers.
“The rate of supplementation was lowest in freshmen and rose continuously to the 12th grade,” he said. “Eight percent of freshmen used creatine and 23 to 24 percent of seniors did.”
The strength gain motivates adults as much as high school athletes to try creatine.
“It seemed like a way to put on more weight and get more power,” said Kim Landry-Ayres, 30, of Eau Claire, who owns her own fitness business, Mission Accomplished.
Landry-Ayres has had a long-term interest in fitness and has a medical background as well.
“I’ve been a competitive bodybuilder and trainer for about 10 years and graduated as a nutritionist in 1997,” she said.
Landry-Ayres was a field hockey player in high school and at Longwood College, Va., where she majored in Pre-med. She earned her associate degree in medical assistance from Apollo College in California and later got her dietetic degree from UW-Stout. She has many other fitness certifications as well.
Peterson came from a fitness background quite different from that of Landry-Ayres. As a young man who weighed 240 pounds his freshman year of high school and played a lot of video games, Peterson said he knew he needed a life-style change. “The hormones just kicked in and said, ‘You’re never gonna get a girlfriend if you keep looking like this,’” he said.
The summer after his sophomore year, Peterson lost 80 pounds by running regularly, building from one mile each day to four miles per day. He also tried to eat more fat-free foods. “When you get more active you seem to eat a lot less,” he said of his transformation. “All I ate my junior and senior years was spaghetti noodles and tuna. I probably didn’t break 10 grams of fat per day.”
Peterson heard about creatine when he was in high school from boys on the football team, his accounting professor and his best friend, but hesitated to use it at first. “I was always a kid who never put anything in my body unless I was sure it was safe,” he said. “I wouldn’t take it ‘til I knew enough about it. I didn’t feel that we, as humans, knew very much about it. People were just taking it based on what they’d heard.”
Landry-Ayres said at the time she hadn’t heard anything that made her hesitate to use creatine.
“I didn’t feel like there was any hazard in taking it,” she said. “I had heard of some people cramping, but I think if you’re well hydrated it’s not a problem.”
How does creatine play a role in exercise?
There are several theories about how the body uses creatine during exercise, but one of the most popular ones depends on the phosphorylated nature of creatine in the body. In the muscle cells, 60 percent of creatine is converted to phosphocreatine (PCr), according to an article in the Journal of the American College of Nutrition.
Creatine is believed to assist the muscle’s “energy server,” adenosine triphosphate (ATP). “When a phosphate is used it creates energy and becomes ADP (adenosine diphosphate) and can no longer contribute that phosphate for energy,” said David Van de Loo, a medical doctor with a specialty in sports medicine at Luther-Midelfort Clinic, Eau Claire. The creatine is attached to a phosphate and can contribute that phosphate. “It rephosphorylates low-energy ADP to the high-energy ATP which is then the energy source for short bursts (of exercise),” Van de Loo said.
Another theory, Van de Loo said, is that creatine improves diffusion by allowing phosphate into the cells more easily than it would be in the absence of creatine. Other theories include one that says creatine causes a breakdown in glycogen to release energy, or that creatine may have some acid buffering effects that may allow for changes in the cell that would improve energy availability.
What dosage should a person take?
As with almost every aspect of creatine usage, experts and users disagree on what is an appropriate dosage of creatine for those wishing to use it as a supplement. Creatine monohydrate is usually taken in powder form, though it can sometimes be found as a pill. Foos says this is because the powder is the most cost-effective form for the manufacturer to make.
“Liquid creatine is absorbed faster into the bloodstream, but it hasn’t been proven whether that builds muscle faster,” Foos said.
The usual dosage pattern involves a loading phase and maintenance phase, though some say the loading phase is not needed.
The purpose of the loading phase is to increase the body’s stores of creatine and lasts between seven and 10 days, according to the aforementioned primer on creatine supplementation. The primer said that if more than 20 grams of creatine are ingested each day during the loading phase, the excess creatine will be excreted through the urine rather than stored.
After loading, a maintenance dose of 2 to 5 grams of creatine are usually taken each day. “Simply starting and maintaining a maintenance phase will, over time (usually two to four weeks) lead to identical creatine levels with or without a loading phase,” the primer said.
To calculate the amount of creatine to use per day during the loading phase, the primer on creatine supplementation recommends a ratio of 0.3 grams per kilogram of body weight per day. The ratio for the maintenance dose is 0.03 grams per kilogram of weight per day. The primer uses the example of a 176-pound (80-kilogram) male, who should take 24 grams of creatine per day (80 * 0.3 = 24) during the loading phase, and 2.4 grams per day (80 * 0.03 = 2.4) as a maintenance dose.
Peterson discussed the option of creatine supplementation with his physician. “The worse thing my doctor told me was that it might be hard on my kidneys like any other supplement would be,” he said. “It would be no harder on my kidneys than vitamins, o.j. or other supplements.”
Towards the end of high school, Peterson used creatine for 11 months straight. He began with 20 grams per day for four days (the loading phase) and then took 5 grams per day after that as a maintenance dose. He said the manufacturer recommended loading once a month but his doctor told him that was unnecessary. Peterson went off creatine for a while because he said he wasn’t lifting regularly enough, but began using it again in Nov. 2000 and is still on it.
Landry-Ayres says that she first tried creatine seven or eight years ago because from what she learned in school, it seemed like it might be a legitimate supplement.
“I knew by then that good nutrition and hard training was the only thing that really worked in terms of getting yourself really in shape,” she said. “It seemed like the way they were promoting creatine in the studies at my school seemed like biochemically (creatine) might actually work.”
Landry-Ayres said she followed the manufacturer’s instructions at first: she loaded with 5 grams per day and then used 1 gram twice a day as a maintenance dose. She cycled the creatine by taking it for three weeks and then going off it for a week or two before resuming.
“(Manufacturers) want to sell lots of pills,” she said. “They want you to finish up your bottle real quick.”
Landry-Ayres decided the recommended amount wasn’t really necessary and cut back to only 1 gram of creatine per day. She used the powder form of creatine mixed in with water at first and later put it in a protein power drink or juice. She was also taking glutamine, a multi-vitamin and some other amino acids at the same time.
McGuine said the recommended dosage by most experts is to take three to five grams per day for long-term use, and cycle it on and off for 12 to 14 weeks at a time.
“There isn’t a standard way to use it,” he said. “Every manufacturer has a different method and suggestions.”
Van de Loo agrees. “(It’s) more trial and error like a health food would be. There is no specific recommendation.”
Van de Loo said the only recommendation he’s heard is to take 20 grams a day during the loading phase (one week) followed by 2 to 5 grams per day in a four to 12-week cycle. He noted that this recommendation has not been scrutinized by a physician like a prescription would be.
“One of the problems that you can get into is that people hear the claims and ask, ‘Okay, how much am I supposed to take?’ and they think that if a little bit is good then a lot is good and that can lead to all sorts of problems,” Tio said.
Does creatine really produce results?
Whatever the scientific mechanism and dosage, many researchers and users of creatine agree that creatine seems to act as an energy-provider during certain types of exercise.
Peterson said when he first took creatine it was about two weeks before he saw results. He would spend three hours lifting weights four days each week. “I was more energetic when I left than when I got there.” He also ran and played basketball. “The only time I ever dunked was on this stuff,” he said. “It was fantastic.”
“I think it’s fantastic,” Peterson said. “You lay down on the bench and do three sets…your third set is better than your first.”
“It doesn’t make me stronger, it keeps me from getting tired so I can train harder and lift heavier weights,” he said. “It helps your stamina.”
Peterson, who is 6 feet tall and about 175 pounds, could bench press as much as 240 pounds when he started college and was taking creatine regularly. He said he currently exercises four days a week and lifts between 190 and 200 pounds.
Landry-Ayres said she was exercising at least five or six times per week while she was taking creatine. Her cardiovascular performance remained about the same, but her weightlifting was noticeably improved, she said.
“Within the first cycle I started to notice a difference,” she said. “I gained five pounds right away (in the first couple of weeks). Definitely some of my heavier lifts, squatting and bench pressing, I was stronger. The muscle looks fuller.”
“There’s some reason to believe it may be beneficial for athletes that are highly involved in anaerobic activities such as high-intensity sprints and resistance weight training,” Van de Loo said. “It doesn’t seem to be beneficial for those who do aerobic activities.”
“Creatine will affect the energy system involved in short bursty kinds of activities like the 100-meter dash,” said Tom Tio, a clinical dietician at Luther Hospital. “You may be able to recover from that activity, enabling you to run it in a shorter amount of time. You’re able to do it again faster.”
“The jury’s probably still out on whether it’s actually beneficial,” he said. “We know that it increases the amount of creatine available to the body, but it’s less certain whether it’s actually having this beneficial effect.”
“Some of the studies have shown it’s good in activities lasting less than 15 seconds like lifting, sprinting,” McGuine said. He says that much of the research being done on creatine may not hold true for athletes because most studies use male graduate students in the laboratory. Although creatine apparently helps in lab tests with short bursts of activities like high-speed cycling, “the way they’re measuring it doesn’t correlate to being a better athlete on the field,” he said. “I haven’t seen well controlled, well conducted studies that are done on the field. I haven’t seen it yet,” McGuine said.
Most medical experts remain skeptical about creatine: its benefits, risks, and side effects.
“There are no documented results,” said Jane Foos, a dietician at Red Cedar Clinic in Menomonie. “Any results one hears are primarily subjective from the view of the athletes. Athletes say they had this…it’s all reported subjectively.”
“There’s no documentation to show that creatine improves performance because there are so many other factors: the athlete’s fluids and hydration, diet, training techniques,” she said.
A study by Mihic et al of the Departments of Kinesiology and Medicine, McMaster University, Hamilton, Ontario, Canada, published in the Feb. 2000 issue of Medicine & Science in Sports & Exercise, found that acute creatine monohydrate administration does not affect blood pressure, renal function, or plasma creatine kinase activity, but that it did increase fat-free mass. It was also found that the effect of creatine monohydrate upon fat-free mass was greater in men than in women. The study examined 15 men and 15 women between the ages of 20 and 24 that exercised three to four times per week. The participants took creatine or a placebo for five days.
What about side effects?
Peterson said he never experienced any side effects from creatine. “A side effect with this is that if you don’t drink a lot of water you cramp up quite a bit. I’ve always felt thirsty, but no side effects really,” he said. “My best friend and I bought (bottles of creatine) together and he experienced a lot of problems with pulled muscles and stomach cramps because he didn’t drink enough water.”
Landry-Ayres said the only side effect she noticed was the weight gain.
“(I felt) more motivated to work harder. I think I struggled with (the weight gain) a little but I knew why it was happening so I learned to accept it, but that’s part of the reason I went off it eventually.”
She said she thinks women would mind the weight gain more than men in general.
“For a woman, it’s kind of a mental thing because … most women see themselves at a certain body weight and when you’re on creatine you put on weight, mostly water weight, and most of them (stop because they) don’t want the extra weight even if it’ll make them stronger in the long run,” Landry-Ayres said.
Landry-Ayres used creatine on and off for a couple years and hasn’t taken any consistently for three years now. There were several reasons she discontinued its use.
“I wasn’t competing and I didn’t feel like I wanted to be five pounds more and it seemed like to take anything in excess is dumb and a waste of money,” she said.
Foos said supposed side effects can include weight gain, dehydration, a higher rate of muscle cramping, and nausea when loading creatine. She said it’s also a potential carcinogen. “None of that stuff has been proven yet,” she said.
“Unlike drugs that are tested for years and you know (the effects), no research like that has ever been done on creatine or any other of these so-called natural supplements,” McGuine said. “Because it’s considered a food supplement it doesn’t have to meet FDA guidelines.”
McGuine said that in his study with Sullivan, one out of five high school students using creatine had experienced unwanted side effects.
“A lot of boys think there’s a side effect of sexual dysfunction like with steroids,” McGuine said. “That’s a common misconception.”
According to the Canadian Journal of Applied Physiology article, “the one “side effect” supported by research is a very rapid weight gain. … Consensus today is that weight gain after the creatine loading … can range from no gain to a gain of about 2 kilograms after five days. … It is still far from clear what proportion of that weight gain is due to fluid retention and what proportion is due to an increase in lean body mass.”
Is creatine safe for long-term use?
One of the problems with creatine supplementation is that most studies, like the one by Mihic et al, only evaluate the supplement for a short period of time. Very few studies have actually examined the long-term effects of creatine. In fact, the Canadian Journal of Applied Physiology asserts, “There are no prospectively designed published investigations documenting the incidence of side effects in healthy individuals with long-term use of creatine.”
“Creatine might cause a little more stress on the kidneys,” Tio said. “It tends to make the muscles hold on to more water, which makes people think they’re bulking up.”
“The safety of the long-term use of creatine really hasn’t been established,” he said.
McGuine agrees that the kidneys may be overworked because of creatine supplementation.
“Theoretically (it can harm) the liver and kidneys, which get excess protein out of your system,” McGuine said. “The liver has to transform it to flush it out. If you make an organ work hard day after day it gets tired, it gets sick, it gets cancer.”
Given these potential risks, McGuine said he doesn’t think creatine is worth its supposed benefits. He said French researchers are concerned about a cancer risk, so creatine is banned in France.
“There’s very limited evidence that it will help you,” McGuine said. “You’re really taking a large risk in taking it for the benefits you’re going to get from it. If you’re consuming enough protein you won’t need (to supplement) creatine.”
McGuine said taking 1 gram of protein for every 1 kilogram of body weight each day is sufficient.
“I don’t know (about long-term effects),” Van de Loo said. “You just don’t know ‘til you get down the road.”
Landry-Ayres doubts scientists will discover any negative long-term effects from creatine use.
“I think (creatine) is probably fine,” she said. “I never had any negative side effects.
“I was really surprised to find out they were linking it to cancer. I think anything can cause cancer, hotdogs or whatever, but because (creatine is) something our bodies already produced, I’d recommend it with caution. I would never recommend people staying on anything long term.”
As a fitness trainer, Landry-Ayres tries to stay well educated about products on the market.
“Even scientific studies are biased. … (the results are usually) what the scientist expects to happen,” she said. “You have to be really careful as a professional what you promote because … the media can turn it all around and make it hard for people to believe anyone else.”
Peterson, having heard about the possible long-term risks of creatine use, isn’t too worried.
“There’s always that uncertainty,” he said. “What if it is hurting me, hurting my kidneys? It’s better not to use it ‘til you really need it. You gotta know that the pro-athletes (like the St. Louis Cardinals’ Mark McGwire or the Chicago Cubs’ Sammy Sosa) are taking way more than we are, anyway.”
Why hasn’t creatine been studied more closely? Will it be soon?
“It’s really hard to study something like that with a minimal effect and only some people responding,” Van de Loo said. “…It’s hard to discuss the maximum dosage.”
“(There’s) no incentive for research because so many people sell it,” McGuine said. “(You) couldn’t get a patent for showing it works.”
Tio says the outlook for future research is favorable.
“There’s not a lot of motivation for the companies selling it because they’re selling the heck out of it already,” he said. “(But) there’s so much interest in it already that researchers might migrate to that.”
What would you say to someone considering creatine use? Would you recommend it?
Tio offers advice to those considering using creatine as a supplement.
“I would first of all tell them to let their physician know they were doing this, and as a dietician question them seriously about their diet practices…try to educate them on the product, let them know about detriments,” Tio said. “When a person comes in to a health professional, a lot of times they’ve already made up their mind on what they’re going to do with it. It comes down to the person’s decision and that’s why education is so important.”
“It has no approval of any kind from a medical standpoint,” Van de Loo said. “I do not directly discourage its use but I wouldn’t recommend it either.”
“(At Big 10 schools) physicians have advised the athletic programs not to provide it to the team members,” McGuine said. “If it causes cancer they will sue the university later. Let them use it, but don’t provide it.”
Although she wouldn’t recommend using creatine, Foos says the youngest age a person should begin creatine use at is 18 because a person’s body is mature and the creatine is less likely to interact with other hormonal changes. “All studies have been done on people older than 18, the age of consent,” she said.
Foos said she thinks there are alternative ways to achieve a healthy, toned body without using creatine.
“There are other ergogenic aids that could improve performance that are safer and have been proven to work,” she said. “Fluids and carbohydrates, pure and simple.”
Tio agrees. “(People should) place less emphasis on supplementation and more on doing what they need to do to help them improve their technique and be successful in their sport…through hard work and coordinated training and a planned schedule.”
Peterson says he’s pleased with the results he gets from using creatine and would definitely recommend it.
“You better be lifting to use it,” he said.
Peterson says people should have the right motivation for taking creatine.
“I wouldn’t recommend it to a young kid. I think maybe you shouldn’t start taking it ‘til you’re 16,” he said. “I think kids are just too quick to say ‘I want to lift weights and I want to take creatine right now.’”
Landry-Ayres says the safety of creatine is too sketchy for her to confidently recommend it anymore.
“Now there’s news that creatine may be carcinogenic and until all that’s ironed out I don’t know if I’d recommend it to anybody,” she said. “Creatine is more of an ergogenic for competitive athletes. I don’t think the average person needs to take it or even should be.
“(If someone wanted to use creatine) I’d ask them why, and if they had (a good answer) … I would hope they would do some self study on it before they get into it or anything.”
Although she no longer uses creatine, Landry-Ayres takes several supplements, including a multi-vitamin, calcium, magnesium, anti-oxidants, co-enzyme Q and Omega-3 fatty acids.
Can creatine be trusted?
Whether creatine is really safe to use long-term remains questionable and certainly warrants some careful thought. McGuine and Sullivan’s article, “Creatine & other dietary supplements: Help or hype?” published in the Nov. 2000 issue of Wisconsin School News, offers several tips for those considering using creatine or any other supplement. First, ask your health care provider for information about the supplement you are considering. They may not know everything about the product, but they may have access to more information that they could pass along to you. Contacting your physician is also important to ensure that the supplement you may be using would not interact with any other medication or supplements you are taking.
Also, remember that supplements are not substitutes for tried-and-true methods for achieving better health and a better physical appearance. As the Wisconsin School News article says, “in the long run, a supplement cannot make up for other poor health choices (lack of rest, improper nutrition, recreational drug and alcohol use, and so forth).”
Get educated: examine the “Supplement Facts” label on the product and contact the NIH-ODS online at http://odp.od.nih.gov/ods/databases/ibids.html, which has information from both researchers and consumers about various products. If you have a negative reaction or serious harmful effect that you think may have been caused by a supplement you are using, report it to FDA MedWatch at http://www.fda.gov/medwatch/report/hcp.htm or call 1-800-332-1088.
Beware of red flags: Just because a product is “natural” doesn’t ensure that it’s safe to use. Many compounds that are good in moderation can be dangerous if consumed in excess. Also, phrases like “new discovery,” “breakthrough,” “miracle,” etc. that make a product sound too good to be true means that it probably is. If a product points to science that supports its results, but relies on the results of only one study, has no reference list or uses data collected at a company lab, the results may be biased. Remember that if a product is powerful enough to have amazing effects, it is also strong enough to have side effects. Finally, beware of ads that claim the medical profession or the government withheld a product that could benefit many. While there are many supplements that may assist a person in improving their athletic performance, the potential benefit isn’t worth the risk if a product’s safety is uncertain.
Landry-Ayres says supplementation safety comes down to personal responsibility.
“I think it’s important that people take responsibility for their own health and know what they’re putting into their bodies,” she said. “If people don’t take responsibility for what they put into their bodies you get the same sort of consequences as what’s happened with the tobacco industry. The lawsuits are kind of frivolous with people saying, ‘Well, I didn’t know tobacco was bad for me.’”
A primer on creatine supplementation. Madison, WI: UW Health – University of Wisconsin Sports Medicine.
Jacobs, I. (1999). Dietary creatine monohydrate supplementation. Canadian Journal of Applied Physiology, 24, 503-514.
McGuine, T., & Sullivan, J. (2000, November). Creatine & other dietary supplement: Help or hype? Wisconsin School News, pp. 5-8.
Mihic, S., MacDonald, J., McKenzie, S., & Tarnopolsky. (2000). Acute creatine loading increases fat-free mass, but does not affect blood pressure, plasma creatine, or CK activity in men and women. Medicine & Science in Sports & Exercise, 32 (2), 291-296.
Williams, M. & Branch, J. (1998, June). Creatine supplementation and exercise performance: An update. Journal of the American College of Nutrition, 17 (3), 216-234.
To read more, a subscription is needed: Click here to subscribe