Consumers and Nutritional Supplements: Could This Be Me? This Is Me!

ABSTRACT - Increasingly, athletes and health-conscious consumers may take supplements to enhance physical performance. In this study, we report interviews with recreational body builders exploring their use of nutritional supplementsCparticularly their initial trial, development of committed use, and the informational and social influences on those decisions. The interaction of personal and media sources lead to initial trial. The informants became committed users after investing significant time, energy, and money exploring supplements. They undertook the committed behavior as a way to improve their perception of self. Informants did not seem to be at all critical of the objectivity of various sources of information.

Citation:

Marlys J. Mason and Debra L. Scammon (1999) ,"Consumers and Nutritional Supplements: Could This Be Me? This Is Me!", in NA - Advances in Consumer Research Volume 26, eds. Eric J. Arnould and Linda M. Scott, Provo, UT : Association for Consumer Research, Pages: 107-112.

Advances in Consumer Research Volume 26, 1999      Pages 107-112

CONSUMERS AND NUTRITIONAL SUPPLEMENTS: COULD THIS BE ME? THIS IS ME!

Marlys J. Mason, University of Utah

Debra L. Scammon, University of Utah

ABSTRACT -

Increasingly, athletes and health-conscious consumers may take supplements to enhance physical performance. In this study, we report interviews with recreational body builders exploring their use of nutritional supplementsCparticularly their initial trial, development of committed use, and the informational and social influences on those decisions. The interaction of personal and media sources lead to initial trial. The informants became committed users after investing significant time, energy, and money exploring supplements. They undertook the committed behavior as a way to improve their perception of self. Informants did not seem to be at all critical of the objectivity of various sources of information.

As consumers search for alternatives to enhance their health and athletic performance, sales of dietary supplements are soaring. In the last 4 years since the passage of the Dietary Supplement Health and Education Act, he supplement industry has grown from $8 billion to $12 billion (Editorial in New York Times 1998). Creatine alone has become a $100 million industry (Springen and Peyser 1998). New products and brands are inundating the supplement market. With this rapid growth, consumers are facing a marketplace with increasing numbers of alternatives and many sources of information.

Information about supplements can be gleaned from articles in scientific journals and specialty sports/health magazines, from media advertising, point-of-purchase promotional material, input from sales representatives, and users. Supplement advertising has risen considerably with expenditures in 1996 increasing by almost 30% (Wilke 1997). Many supplements are sold exclusively through network sales organizations and many sales reps are users. Currently, available information about the affects of supplement use is incomplete since very few controlled and long-term studies have been conducted. Additionally, because of the different regulatory standards for information disclosure in various sources (e.g., product labels, advertising, and personal selling), consumers are likely to find inconsistent or even contradictory information as they consider the use of supplements.

In addition to commercial information about supplements, consumers may also be influenced by many professional and collegiate athletes who tout the performance enhancement benefits of new supplements. Despite the NFL, NCAA, and Olympic bans on androstenedione (touted as a natural steroid), the supplement has gained great popularity after Mark McGwire praised its use in helping him break baseball’s homerun record. Another supplement, Creatine (taken to enhance muscle size and strength gains), was reported to be taken by one third of the 14,000 collegiate athletes in America even though the NCAA recommends against it (Schrof 1998). The publicity surrounding the use of supplements by collegiate and professional athletes is likely impacting consumer use.

In this paper, we examine the commitment of consumers toward maintaining the health behavior of dietary supplement use. Our specific objectives are to: 1) explore the motivation behind initial trial of supplements; 2) examine the social and intrinsic influences on continued, committed use; and 3) investigate consumer expectations for and evaluation of product performance. We are particularly interested in understanding how consumers evaluate the impact and value of taking supplements, if and how supplement usage relates to/affects other health behaviors (e.g., seeking medical treatment, eating a nutritious diet), and the extent to which supplement users tell and ask other consumers about their positive and negative experiences. We attempt to better understand consumers’ reliance on the variety of information sources available and ways in which these sources interact to establish, expand, and/or confuse consumer knowledge of supplements’ potential effects, both positive and negative.

METHODS

Open-ended, in-depth interviews were conducted with health-conscious consumers in the intermountain west. The participants were recruited from three different health clubs in the area. Participants include five men and one woman ranging in age from 22 to 42 years old with varied careers and socio-economic backgrounds. A common characteristic of our participants was that they took a dietary supplement (e.g. creatine) to enhance their strength, stamina, and physical performance and image. Their experience with taking supplements and other performance enhancement substances ranged from 3 months to 22 years. Analysis for emergent themes was conducted separately by the authors. Particular attention was given to motivation and influences on trial and continued use of supplements as well as participants’ expectations for and evaluation of product performance over time.

EMERGENT THEMES

Consumer’s motivation to use dietary supplements for physical enhancement appears to change over the course of their experience with the product. Consumers first go through a phase of exploration in which they begin to take a supplement and evaluate its impact on their body and health. Once the consumer is comfortable with supplement use and has observed/identified the positive effects, he/she is motivated to become a dedicated user by other, deeper influences. In a study of committed behavior, Scammon (1987) observed that as one becomes increasingly intensely committed to a behavior there is likely to be a rejection of alternative activities in order to focus more upon the chosen behavior, investment of 'side bets’ which encourage future commitment, some affective reward for commitment to and achievement in an activity, and a competitive element to the commitment to the behavior. Similar to Scammon’s observations, as the participants in our study become more personally invested in improving their body image and physical performance, their acceptance of and commitment to supplements becomes more pronounced. Within the stages of exploration and committed use, we explore several themes.

The Exploratory Stage

Initial Awareness and Interest. For our participants, the decision to initially experiment with supplements was not a spur-of-the-moment one. These consumers made a conscious choice, and what they thought was an informed one, after searching for information and talking to others about the products. They become aware of the performance enhancing benefits of supplements through media sources such as advertising and news/sports articles and also by talking to others including friends who work out or 'professionals’.

Advertising has a lot to do with it [initial use] and word-of-mouth. Those are the two big things. You have to understand that in advertising, you look at the advertisement because #1 you’ve never taken that product before. 

#5, male, 42 yrs.

I’d heard about it [creatine]. You hear about these things, you hear about a lot of things. And I have some friends that I work with. One of them said, "You should be on creatine. You should try it. It really helps you with the strengthening." So actually he’s the one who first introduced me to it.

#6, female, 33 yrs.

I went to a bodybuilding contest and I talked to a guy who was a bodybuilder. He was a competitive professional bodybuilder and was actually selling these amino acids at the contest. I was just a 16-year-old kid; of course I bought them. Then from there reading the muscle magazines.

#3, male, 32 yrs.

Interaction of Personal and Media Influences. The interaction of both the media and personal sources was crucial to experimenting with supplements. Our participants became aware of supplements and their benefits through advertising, articles, and news/sports reports. However, the consumers did not initially try a supplement without talking to someone who had personal experience with the product. When the seller was an actual user and the consumer could see the results that they were striving for at the point of purchase, the personal testimony seemed particularly strong.

Search and Consideration. Once one supplement has been tried, or participants begin to actively seek information about other products and their benefits. They again search for information from a variety of media and personal sources but now the search becomes more aggressive and focused. Their media search commonly includes reading magazine articles (e.g., Muscle Media, Men’s Fitness), journal articles (e.g., Journal of Sports Medicine), advertisements, and visiting websites. They also may ask different personal sources such as peers in the fitness community, sales personnel at supplement stores, and the customer service personnel of the producers. As described below, our participants invest significant time and effort into finding information about new supplements:

If I see an advertisement or if I hear something on the news, then I study it [the supplement]. In the library there’s the journal of medicine and they have different studiesAlso EAS¹ has a magazine called Muscle Media. I study that and usually if you write to them you can ask them about different supplements. They’ll tell you everything they know about them. They can send you all the articles, all the facts, all the tests that they’ve done and you can study it yourself.

#4, male, 26 yrs.

Usually I would go to at least 3 or 4 nutritional stores because every nutritional analyst [sales staff] would tell you something different. They would say 'Well, it’s better if you take it this way or this stuff doesn’t work, this stuff does work." I would kind of make my own notes. I’d go home and write everything down and then just kind of figure I’m going to try this. Also, I would buy a lot of fitness books.

#2, male, 27 yrs.

Our participants used different information sources to learn about the effectiveness and safety of new products. Our examination of available information suggests that reported studies of effectiveness are frequently conducted by the producers and that users often are sellers. Yet our participants do not seem to question the objectivity of this information. The informants simply take the information as fact and do not assess the motivations of the seller or the potential for deception. The following participant discusses his use of a manufacturer’s promotional material for obtaining credible information:

Informant #1: The Sports Supplement Review just talks in general about certain supplements. Not specific brands or anything. Just the supplements in general and what they do, what effects they have. It’s kind of like a dictionary or an encyclopedia about supplements.

Interviewer: Who writes that?

Informant #1: Bill Phillips. He’s the CEO of EAS. He pushes his products a little bit but he also talks about other people’s products too. So he sounds pretty legitimate, credible.

Interviewer: Does he give side effects then?

Informant #1: Yeah, he talks about certain things and he’s really straightforward about stuff. So if there’s something that he doesn’t think is beneficial to anybody he’ll just kind of say "Then there’s this, and there’s really no effect or benefit rom using this" and then he’ll move on.

Interviewer: Does he ever knock his own products?

Informant: (a pause) No. Of course not. He doesn’t. You know, I don’t really remember him knocking too many products.

Furthermore, the informants seemed to disregard or rationalize negative information and feedback about the supplements. When faced with a FDA disclaimer on supplement labeling, rather than question the type and quality of studies (e.g., longitudinal tests of long-term effects) that have been conducted, the participants dismissed the FDA’s role in ensuring product safety and effectiveness. Even greater rationalization occurred when confronted with a negative personal experience with use of the supplement. This disregard for negative information is seen in the following informants:

If I’ve read all the studies on it [creatine] and all the studies don’t have anything wrong with it, then I don’t worry. I think that it’s [the FDA disclaimer] mainly just to protect themselves [the manufacturers] from a lawsuit.

#4, male, 26

One of the side effects from creatine is that you get a lot of cramps. I get cramps off itIf I’m cramping I know it’s because I’m not getting enough water [to counter the effects of creatine]. If I was getting some side effects that I didn’t know why I was getting it, I would stop.

#3, male, 32

The participants rationalize the negative information that they have received and focus on the positive, and potentially one-sided, information that is distributed or funded by the producer. This behavior suggests they are motivated by a more latent motivation than pure information.

Self Image. Although our informants reported that their initial trial of supplements was a considered choice, they were stirred to purchase and use by a deeper motivation. Underlying their experimentation with supplements was a discontent with their self-image, particularly their physical image. The participants reveal their feelings of inadequacy and the desire to change their appearance in order to have a better perception about themselves. They are concerned both with how others see them,

I care about what other people think about my appearance for some stupid reasonI feel like if my appearance isn’t right then people might not take me seriously.

#4, male, 26 yrs.

and about how they see themselves,

I’m a real hard judge on myself. I judge myself really harshly. When I don’t do certain things the way that I should be doing them I really bug myself. I feel like a failure. That’s what drives me.

#4, male, 26 yrs.

When you’re dealing with yourself, public image, and the fact that you’re growing older, you always look back at your personal best at one time. Being a former athlete, obviously your personal best was supposedly during those times when you were in college, which isn’t always true. I think I’ve always had that competitive edge just with myself. My own contest and little bit of narcissism where you go 'oh I think I can be a little better here. I can look a little better this way.’

#5, male, 42 yrs.

Belk (1988) proposed that a consumer’s self-identity is an extension of their possessions including his/her body. Our participants reflect this thinking through their attempts to improve their body in order to raise their overall perception of themselves. Our informants reveal an aspirational motivation (Sherif 1953) in which they have an ideal body image that they attempt to achieve, even if that ideal was a personal best from their youth. Our participants also reveal a dissociative motivation in which they have a negative image from which they want to dissociate themselves:

And for God’s sake please don’t make me an 80-year old man, or a 40 year old man, in a little teabag bikini bottom with the stomach hanging out.

#5, male, 42 yrs.

They maintain certain behaviors (e.g., working out, using supplements) in order to avoid this unfavorable image.

Belk (1988) further suggests that some body parts may be more central in defining a person’s image of self and that this importance is seen in the care and maintenance of the body part. Our participants viewed their bodies as critical elements of their self-image. They focused on specific body parts such as biceps, chest, and waist in their workout routines and judged them more closely to assess improvements. One participant reveals this focus on specific body parts when he discussed stopping his workouts for two weeks when he got married:

I stopped working out and I lost a lot of weight up here [his chest] and it went down to my stomach. I gained about 4 inches on my stomach. I was just kind of ugh. That’s why I’m back on track again.

#4, mle, 26 yrs.

Our participants’ behaviors may also be compared to consumers undergoing aesthetic plastic surgery on various body parts (e.g., nose, breasts) (Schouten 1991). Through surgery, Schouten’s participants reconstructed an inadequate body part to an idealized one in order to improve their body image and create a more positive perception of self. Our participants may identify even more strongly with their new self-image than surgery consumers because they have 'earned it’. Using steroids would be the quick fix like surgery. But our participants view supplements as a complement to other health behaviors including intense workouts and optimal nutrition.

I can’t spend $50 on a bottle of Creatine and go eat this or drink a bunch of beersYou’re not going to get the maximum benefit out of your supplements if you’re not eating correctly, or changing your routine or really working hard in the gym. I could take Creatine all day, but if I’m not in the gym doing what I’m supposed to do its not going to have an affect on me.

#3, male, 32 yrs.

When I take supplements it encourages me to eat better because I want to complement the money that I’m spending on these supplements with a good diet. I don’t want to take good protein with the creatine and then complement it by eating lots of chocolate candy bars and ice cream because I’m basically just wasting what I’m spending money on. So I’ll complement them with a good diet of some white meat, vegetables and fruits, rice and beans, potatoes and things like that. Also, I really work out hard during the times that I’m taking the protein and the creatine. I look to maybe adding more weight to my workouts; maybe a different, longer routine; adding different exercises and something I haven’t tried before. It makes me feel like maybe I’ll get more for my money if I work out harder.

#2, male, 27 yrs.

The informants reveal their commitment to achieving a better self-image through a commitment to a combination of workouts, supplement use, and nutrition. They also reinforce their commitment through sacrifices, particularly financial sacrifices. The supplements are a notable financial cost for these informants or may even be considered a 'side bet’ as discussed by Scammon (1987). By making significant financial investments in supplements (as well as health club memberships, magazine subscriptions, workout clothing) they helped to ensure that the behaviors would continue. The following informants talk about the amount of money they invest in supplements:

If I had more money, I’d spend around $200-$300 a month. Right now, I spend probably around $100 a monthIf you do have anything for guinea pigs, if you want me to test anything. [I’m willing] for free.

#4, male, 26 yrs.

It [supplement use] affects me that way more financially than anything. I spend about anywhere from $150 to $200 a month.

#3, male, 32 yrs.

The Committed Stage

Self-Identity. As consumers continue their use of supplements and experiment with new products, they become committed users of supplements. They’re no longer questioning the value of the supplements they’re taking because they 'know’ they work. The participants are avid believers in the effectiveness of the product and strongly identify with their positive body image. In fact, they define themselves and are defined by others by this image.

It is as much a part of my personality as anything else. Its not solely what defines me but it is a huge piece of what defines how people know mepeople pop their head into my office and they don’t ask me how work is. They ask me about my workout or they’ll ask me questions about creatine.

#3, male, 32 yrs.

This positive, new self-image and the feelings of achievement that supplements have helped them obtain seem to bolster their self-confidence in other aspects of their lives:

It’s good just because you’re achieving things. It helps you out in life because you know you can achieve things. When you reach that [a goal] it just adds a new spark. Like you get excited and then it just gives you that much more motivation for the next goal. That’s why I like it.

#1, male, 22 yrs.

This new self-image is also reinforced by social influences. As other people notice changes in the participants’ bodies, they begin to feel better about themselves. Furthermore, this recognition provides an opportunity for them to share information with other people about their supplement use and workouts. Our participants are recognized by others for their commitment and achievement and are sought out by others for their knowledge:

The guys on the other end of the gym and again it’s divided up into bigger guys, smaller guys. Guys who know, they’ll go'what have you been taking because I notice you’re cutting more. You’re gaining more size, more strength.’ So everybody shares a little information.

#5, male, 42 yrs.

Informant #1: Some things I tell people not to even take in here [the supplement store in the health club]. They ask my advice and I’ll tell them what my advice is. Sometimes I tell people not to even get anything, but to do something else, just stay on their diet. They don’t need to spend all that money. And they’ll come back to me for more information and stuff.

Interviewer: For some people, you’re an expert. I mean, you’re their expert.

Informant #1: (laughs) Yeah, just because I know more than them. I’m no expert.

Contact with others using supplements also gives them an opportunity to gain information:

I talk to a lot of people I know, but then again I talk to people I don’t know. Like I’ll be in the club and I’ll see someone and I’ll just ask him what he uses. When you workout for a long time you see people, what changes they’re making so it just kind of sparks an interest.

#1, male, 22 yrs.

A Community Identity. Consumers who participated in advanced skydiving jumps were socially motivated by a sense of community (Celsi, Rose and Leigh 1993). They engaged in a risky behavior partially for the social recognition and a desire to belong to the skydiving community in which acceptance is dependent upon one’s role as a jumper rather than social status or career. Our participants felt this same sort of identity with a group:

There’s really kind of a whole lifestyle. There’s a whole community of people. If you’re in the gym every day you’re talking to the same people who are trying to make the same gains that you are so you start talking. Everybody’s passing information.

#3, male, 32 yrs.

Celci and his colleagues (1993) report that with greater experience, participants in their study developed an increasing interest in achievement and mastery of the activity. This mastery was also socially rewarding because it distinguished individuals within the skydiving community just as our informants were distinguished as 'the bigger guys, guys in the know’. Celci et al’s (1993) skydivers and our supplement users revealed a similar shift in sense of self as their skill level increases, greater goals are reached, and community identification is strengthened.

Individuality Within the Community. Finally, all informants revealed an additional source of motivationBa sense of control over their individuality. Participants very carefully planned their work out and supplementation routines. Their daily schedules were designed around their workouts and times for taking supplements. Eating patterns, and sometimes even work, were shifted in order to ensure time for these routines. The following informants demonstate their desire for control when describing the routine they follow and in planning for it:

I work out everyday at the same time. I usually go between 11:00 and 12:30. I could start anytime between there. I take andro about 30 minutes before I go and I always have nothing in my stomachso I take andro before I go and then when I get back from the gym. There’s about an hour window of opportunity to take the creatine where it’s at its most effective. So when I get back here to the office, I’ll usually drink some creatine and try to have a nice carbohydrate, high protein mid-carb mealIt’s gotten to the point, sometimes I feel guilty about it. I won’t take appointments between 12:00 and 2:00. Yeah, my day is really organized around working out.

#3, male, 32 yrs.

I have a routine. I go to school in the morning. I eat a little bit of breakfast before I go. I come home and I’ll take creatine. I’ll usually take a protein shake in the morning for part of breakfast because it’s easy and quick. I’ll take my creatine, wait a certain amount of time, go work out, come home, take my creatine. Then I’ll have my meal and I’m off to workWhat I like to do is plan ahead of time a program that I’m going to do. I make it out for myself and plan out what supplements I’m going to use. I like to plan it at the time of day when I’m going to use them just so it’s more efficient for me. I save timeI’ve been planning out my last work out for about the past month because I’m waiting until I get ready to take it. I would have liked to already started just because I have it planned out. But I also like to finish my other workouts too.

#1, male, 22 yrs.

Informants further displayed this focus on control when evaluating what routines have worked by maintaining detailed records of their supplements, workouts, nutrition, and shifts in body. They experiment with different supplements and different rituals surrounding their consumption (e.g., when to take them, what to take them with). Then the informants keep lengthy, detailed records of the outcomes:

The protein and creatine are what really helped me increase my muscle mass, my strength. So I experimented with when to take it. Some of the protein would say take it once before you work out and once before you go to bed, or every 2 hours or every 3 hours. I experimented with all of that. I spent a lot of money trying to find just the right thing that would work for meI kept charts of my strength, my strength conditioning, and my weight on a 30-day monthly basis. I would weigh myself and I would measure my body and check how strong I’m getting, how much weight I was lifting. So I would change every 30 days. I did that beginning from about March to August. I went through a process where every 30 days I would change either protein and I would change when I would drink it, how much I would drink of it, the kind of meals that I would eat, and my workout schedules. Every 30 days I would change and then I would keep track of what was working best for me. Then I finally found the right formula that was best for me.

#2, male, 27 yrs.

I’ll keep a workout diary and list the things that I’ve used, the products, for how many weeks. I’ll note specific gains, how I feel, what muscle fatigue feels like the next day if there is any. For instance, when I first stated using creatine, I noted my weight, size of biceps, size of legs, size of chest, the big muscle groups except for the biceps, obviously the arms, but the big muscle groups. I also noted the water content when I was using the Futrex 5000 which checks your body fat but also gives you water compositionI keep track in the diary and then after an 8-week period I go over where I was in the beginning and then take the measurements and necessary information to see if there was any increase. I also chart strength gains, endurance gains with repetition, how many reps at a specified number of weight, and maximum at weight output. So that way I can judge exactly how much this is helping and if its cost efficient to use and if it’s even viable to use it because there’s some real crap out there.

#5, male, 42 yrs.

By tracking their behaviors they are able to chart their progress toward their ideal body image, to evaluate the effectiveness of the supplements, and identify where additional changes need to be made in order to keep improving. Through their journals they monitor what they are doing and how their body is reacting. They are able to develop a regimen that is uniquely theirs. This appears to simultaneously increase their identification with the community of supplement users/body builders and enhance their sense of individuality.

DISCUSSION

In this study we examined the consumer behavior of commitment to the health behavior of supplement utilization among recreational body builders. We explored their initial trial, the development of commitment to use, and the informational and social influences on those decisions. We identified several elements of supplement use that are consistent with behaviors revealed by other research on committed behaviors. For example, our participants demonstrated extreme focus on a constellation of behaviorsBsupplement use was coordinated with workouts and optimal eating patterns. Together the behaviors seem to define a community with which our participants identify and by which others identify them. Seemingly because of the investment in several related behaviors, commitment to supplement utilization is strengthened. Our informants undertook the committed behavior as a way to improve both their perception of self and the image that they perceived others judged them by. They held distinct ideals about the body image which they aspired to achieve in order to improve their overall self-image. For our informants, their achievements and newly attained body image resulted in more than just extensions of self-image; they became the definition of self. An interesting question for future investigation is whether a compulsion develops to support this new self. One informant revealed that, for him, his workouts, supplementation, and eating patterns actually were his first "job" and that everything else in his life was rearranged to accommodate his participation in those routine.

Our informants readily discussed the social side of their supplement useBseeking information from others they admired, asking for advice from sales representatives, and giving advice to others. Despite this social influence on their decisions, they saw themselves as very careful and analytical in their decision to begin taking supplements and their evaluation of the affects of supplements. They mention doing extensive search for information and exhaustive reading about supplements. They see themselves as taking in lots of information from journals and magazines, from advertising, and from personal advice and then analyzing it all before deciding what to take and how to take it, before deciding what is right for them.

However, our informants seem not to be at all critical of the objectivity of various sources of information. They appear to be as influenced by the competitive body builder who is selling his/her personal favorite supplement and the company-sponsored research study that is published in the company-owned magazine. Given the state of the science regarding the effects (both immediate and long-term) of supplements, there appears to be the potential for confusion, and possibly even deception, among this group of users who want to and do believe in the benefits of supplements. In this environment of very little scientific information and limited regulatory oversight over the testing of safety and efficacy of supplements, future research is needed which explores the seeming lack of consumer skepticism about information provided by producers and sales representatives. Current warnings on labels rarely mention specific negative side effects or contra indications but rather simply say that the product has not been approved by the FDA. It would be helpful to know what such a warning means to consumers who are focused on the potential positive effects of product consumption.

Probably because our informants were taking supplements to achieve very specific results (e.g. increase muscle mass or body weight) they were generally very focused on measuring and optimizing those results. Not only did they plan elaborate workout and supplementation routines, they kept very detailed journals of their progress and they consciously tried to coordinate attention to diet and workouts while they were taking supplements. These behaviors seem to indicate that our informants felt a good deal of control over the outcomes and that they actively modified related health behaviors to reach optimal results. Future research should explore the element of control and the relationship of supplement use to other health behaviors in other populations of supplement users (e.g., consumers seeking optimal health, those with chronic diseases).

REFERENCES

Belk, Russell W. (1988), "Possessions and the Extended Self," Journal of Consumer Research, 15 (September), 139-168.

Celsi, Richard L., Randall L. Rose, and Thomas W. Leigh (1993), "An Exploration of High-Risk Leisure Consumption through Skydiving," Journal of Consumer Research, 20 (June), 1-23.

Editorial in The New York Times (1998), "Unregulated Dietary Supplements," The New York Times, (September 19), A14.

Scammon, Debra L. (1987), "Breeding, Training, and Riding: The Serious Side of Horsing Around," in Advances in Consumer Research, ed. Melanie Wallendorf and Paul Anderson, p. 125-128.

Schrof, Joannie M. (1998), "McGwire Hits the Pills: Brawn-Building Supplements Also Deliver Serious Risks," U.S. News & World Report, 125 (September 7), 53-54.

Schouten, John W. (1991), "Selves in Transition: Symbolic Consumption in Personal Rites of Passage and Identity Reconstrction," Journal of Consumer Research, 17 (March), 412-425.

Sherif, M. (1953), "The Concept of Reference Groups in Human Relations," Group Relations at the Crossroads, ed. M. Sheriff and Mo. O. Wilson, Harper & Row (1953), 203-321.

Springen, Karen and Marc Peyser (1998), "The New Muscle Candy" Experts Wrestle with Questions About Creatine," Newsweek, 131 (January 12), 68.

Wilke, Michael (1997), "Alternative Remedies Enter the Mainstream: Marketers Wield Bigger Budgets, Star Endorsers as Presence on Shelf Increases," Advertising Age, 68 (Feb 24), 18.

----------------------------------------