Take Test
Abstract
The escalating obesity epidemic has prompted healthcare professionals to seek interventions that can reach large numbers of individuals in a timely and cost-effective manner. The Internet, with its growing audience, seems an obvious solution. Commercial weight loss programs already abound on the Internet. The purpose of this review is to describe the efficacy of weight loss programs delivered via the Internet in the United States. A search for clinical trials evaluating weight loss via Internet programs was conducted using PubMed, CINAHL, Cochrane Library, Academic Search Premier, the National Institutes of Health Clinical Trials Database, and the Internet as well as a cross-check of reference lists. Eight published studies that met the inclusion criteria were reviewed. Data were extracted on study design, sample characteristics, attrition, weight loss, duration of treatment, and maintenance of weight loss. Of the 8 studies, 3 evaluated the Internet as a means to maintain long-term weight loss. All studies examining weight loss via Internet programs reported positive results, except for one investigating a commercial program. Results from the 3 weight loss maintenance programs conducted on the Internet were equivocal. Because the subjects of all these studies were predominately white, educated women, generalization of findings is limited. Data from the reviewed studies suggest that the Internet may be an alternative to traditional face-to-face weight loss programs. Questions still remain as to the efficacy of using the Internet for long-term weight loss maintenance. Findings from these studies provide beginning guidelines for healthcare providers who may choose to use Internet-based weight loss interventions. Future research is still needed to determine the applicability of such interventions in diverse age, ethnic, and socioeconomic groups.
Today, it is difficult to pick up a newspaper or magazine without reading about the escalating obesity epidemic. These headlines are not sensational but are backed by alarming statistics. According to the 1999-2002 National Health and Nutrition Examination Survey,1 almost two thirds of adult Americans are overweight and close to one third are obese. The prevalence of overweight and obesity has steadily risen, particularly over the last 10 years, among both sexes, all ages, all racial and ethnic groups, and all educational levels.2
Results of a recent study based upon the nationally representative data of the National Health and Nutrition Examination Survey from 1971 to 2002 have adjusted downward the estimates of death due to overweight and obesity.3 Although the findings show that overweight (body mass index [BMI] of 25 to <30) was not associated with excessive mortality, 111,909 deaths were attributed to obesity (BMI >=30), with the majority occurring in persons younger than 70 years and in those whose BMI is 35 or greater. This is not an inconsequential number and still makes obesity the second largest killer following cardiovascular disease. In addition, the new figures address only the risk and not disability or disease. Most likely, these numbers will rise given the fact that the incidence of morbid obesity (BMI >=35) has almost doubled from 4.4% to 8.3% from 1971 to 1994. Medical costs associated with obesity are estimated at approximately $100 billion annually.4 Even more alarming, researchers at the University of Illinois predict that the US life expectancy, after rising steadily for centuries, could level off or decline by 2050 because of the rise in obesity.5
Obesity is an independent risk factor for cardiovascular disease, the number one cause of death for adult Americans in the United States. This is formidable yet remediable. Interventions that target obesity resulting in weight loss also decrease serum cholesterol levels, blood pressure, and insulin insensitivity-the 3 leading modifiable risk factors for heart disease.6
Healthcare professionals and the overweight individual constantly seek ways to lose weight. A meta-analysis of weight loss research revealed that a 15-week diet in obese adults produces a weight loss of approximately 10.7 ± 0.5 kg.7 The addition of behavioral therapy that identifies and attempts to modify eating, activity, and cognitive patterns that contribute to overweight and obesity can improve the success of weight loss programs.8 Although several interventions already exist to assist health professionals in managing obesity,9 the difficulty lies in reaching the large numbers of overweight and obese individuals and providing support for losing weight and maintaining the weight loss they achieve.
The simultaneous burgeoning of Americans' waistlines and their Internet use may be a fortuitous coincidence. The Internet continues to grow as a source of health information for many Americans. In 2002 more than 90 million Americans searched the Internet for health information alone.10 According to a 2001 US Census Bureau report, over 80% of US adults aged 18 years and older use the Internet, including more than 65% at all income levels and greater than 69% across all ethnic categories. Even 59% of Americans 65 years and older use the Internet at home.11 Considering the large number of overweight and obese persons in this country, an intervention that is accessible to a large portion of the population could potentially have a profound effect on reducing obesity's associated morbidity and mortality. Computer-tailored nutrition education aimed at dietary change has been shown to be more effective than general nutrition education.12 Internet-based tailored interventions that incorporate feedback have a greater immediate impact than does general nutrition information on changing dietary behaviors.13
Using the terms "weight loss program" and "weight loss diet" on the Internet search engine Google obtained 678,000 results, a daunting number for anyone browsing the web in search of a weight loss solution. Miller et al7 examined the first 50 Web sites identified by an Internet search that they conducted for "weight loss diets." They compared the content of those 50 sites with published guidelines for obesity management and found an enormous variation in relevance and quality.
Although the US Department of Health and Human Services currently does not classify obesity as a disease, it announced in 2004 that it will expand Medicare coverage to include obesity treatments.14 Although some private insurance companies may cover some aspects of weight loss interventions in select populations, it is likely that more will follow suit given their custom of following the government's intents and actions in health and illness situations. The possibility of Medicare and private insurance reimbursement for weight loss programs almost guarantees the proliferation of such treatments on the Internet.
With more choices for the treatment of obesity and overweight available to consumers and the likelihood of insurance coverage for such treatments, determining the effectiveness of interventions for weight loss becomes even more urgent. The purpose of this review was to examine the efficacy of weight loss programs offered via the Internet.
Methods
A search for clinical trials using the terms "weight loss," "diet," "Internet," and "web-based" in PubMed, CINAHL, Cochrane Library, The National Institutes of Health Clinical Trials database, and the Internet as of June 2005 and cross-checking reference lists produced 14 citations dating back to 1995. Prior to that date, the public did not use the Internet widely or have access to commercial search engines.
Studies included in this review were selected according to 5 criteria: (1) publication in a peer-reviewed journal, (2) randomized controlled trial, (3) overweight and/or obese adults as subjects, (4) the Internet as at least 1 mode of delivery for a weight loss treatment, and (5) weight loss as an outcome measured by a change in either pounds or kilograms. Of the 14 citations, 8 studies met these inclusion criteria. One citation15 was an interim report of a randomized controlled trial being conducted in the United Kingdom whose results are not yet available. Three studies16-18 did not report weight loss in either pounds or kilograms or BMI, and subjects in another 2 studies19,20 were adolescents. Of the 8 remaining studies, 5 examined Internet-based weight loss programs either as stand-alone programs or as part of amore comprehensive health intervention, and 3 examined Internet-based weight loss maintenance programs.
Studies evaluating weight loss and those evaluating weight loss maintenance were examined separately. Because of the varied nature of the interventions, no attempt was made to combine the data for statistical analysis.
Results
The studies evaluating weight loss via the Internet (Table 1) show that weight loss can be accomplished with success similar to that reported by weight loss programs that are not web based.7 The one exception was the study21 that compared eDiets.com , a commercial program available on the Internet to the public, to a 16-lesson, step-by-step manual program, LEARN Program for Weight Management 2000.22
 | TABLE 1 Weight Loss Studies |
The eDiet.com group received a virtual visit from a dietitian, a diet prescription to match their needs, likes, and lifestyles, and customized grocery lists. Online meetings moderated by a professional, a 24-hour help desk staffed by customer service representatives, an animated fitness instructor, online bulletin board, e-mail reminders, and biweekly diet and fitness e-mail newsletters provided support. In addition, participants met with a psychologist for approximately 20 minutes at baseline and at weeks 8, 16, 26, and 52. These meetings provided an opportunity for the therapist to discuss the participant's progress and satisfaction. The treatment manual arm of the study also met with a psychologist on the same schedule as the eDiets.com group. The manual contained behavior therapy lessons addressing changes in diet, activity, and attitude as well as dietary guidelines for weight loss. Participants also were encouraged to keep daily records of their dietary intake. After 16 weeks, treatment manual participants went into a maintenance phase and received The Weight Maintenance Survival Guide.27 Participation for both groups was assessed by the completion of food diaries during the first 16 weeks. In addition, the e.Diets.com group recorded the number of times they logged on. The treatment manual group lost significantly more weight than the Internet group did at weeks 16 (-3.0 ± 3.1 kg vs -0.7 ± 2.7 kg; P = .01) and 52 (-3.3 ± 4.1 kg vs -0.8 ± 3.6 kg; P = .04). Weight loss was positively correlated with the number of visits with the psychologist at 16 weeks (r = 0.41; P = .004) and 52 weeks (r = 0.38; P = .01) and with the number of food records maintained during the first 16 weeks (r = 0.65; P < .001) and at week 52 (r = 0.40; P < .006). However, there was no correlation with log-ins for the eDiets.com group. Despite the unlimited availability of support, the eDiets.com group made little use of those services. In contrast, the treatment manual repeatedly emphasized the importance of keeping food records and was more structured than eDiets.com .
Southard et al25 investigated the effectiveness of a 6-month Internet cardiac rehabilitation and risk factor reduction program conducted over the Internet wherein one component of the program was weight loss. The subjects were randomly assigned to 1 of 2 groups: Internet program or usual care. The authors did not define usual care. An effort was made to have the case manager who saw the participants during the routine office visits be the same person who interacted with them electronically to impart a human feel to what might otherwise be perceived as an impersonal computerized interaction. The Internet subjects lost more weight compared with their usual care counterparts (-3.6 lb vs +0.47 lb; P = .003). The Internet participants' responses to a Likert-scale survey showed that they were, on average, "very pleased" with the program and commented that they had received "quite a bit of social support" from the nurse case managers. A time analysis showed that each Internet participant received 10.8 hours of clinical time over 6 months from nurse case managers and the dietitian. The cost of the 6-month program was estimated at $453 per participant. Both the time and cost figures include calculations that account for components other than dietary, which suggest that a dietary-only intervention would require less time and expense.
Veverka et al26 observed weight loss as a consequence of a 6-month Internet program designed to increase physical fitness in enlisted Air Force men. The airmen were randomly assigned to either a control group with no access to an Internet-based program or the treatment group with access to an Internet program that provided individually tailored nutrition and exercise instruction. Neither group showed improvements in physical fitness, as measured by maximum oxygen consumption, but the treatment group did show the secondary outcome of significant weight loss (-2.2 ± 2.6 kg vs +1.0 ± 3.3 kg; P = .0016). In this study and in the study by Southard et al,25 the control group actually gained a small amount of weight over the course of the study.
Internet interventions that included a behavioral therapy component showed greater weight loss. In a study by Tate et al,23 the behavior therapy group had almost twice as many participants lose >=5% of their initial body weight (45% vs 22%; P = .05) by 6 months. In a second study, Tate et al24 used the Internet as part of a weight loss program but this time targeted adults at risk for type 2 diabetes. This 12-month study compared the effects of an Internet weight loss program alone with that of one with the addition of behavioral counseling through e-mail for 1 year. As in the previous study,23 the addition of behavior therapy doubled the percentage of initial weight loss compared with the basic Internet group (4.8% vs 2.2%; P = .03) and larger mean weight losses at 12 months (-4.4 ± 6.2 kg vs -2.0 ± 5.7 kg, P = .04). These findings imply that an Internet program with e-counseling may be an alternative tomore time-consuming and financially demanding clinic programs.
Weight loss programs using behavioral techniques have increased the average amount of weight loss over the last 20 years by approximately 75% primarily because of increased length of treatment from 12 to 24 weeks.7 In contrast, similar improvements in the maintenance of weight loss have not been achieved. Long-term success of dietary treatment of obesity, defined as maintenance of all weight initially lost or maintenance of at least 9 to 11 kg of initial weight loss for a minimum of 3 years, is only at 15%.8 These findings are regardless of diet type. However, the number of sessions that the participants attended during follow-up correlated positively with weight loss maintained.8 Thus, the Internet could provide an affordable means to maintain prolonged contact with individuals who have lost weight regardless of weight loss program type. Three studies investigating the feasibility of the Internet (Table 2. Available at www.jcnjournal.com ) to deliver weight maintenance programs had equivocal results.
 | TABLE 2 Weight Loss Maintenance Studies |
Harvey-Berino et al28 investigated 46 participants who underwent a 15-week, in-person behavioral weight loss program followed by 22 weeks of maintenance in 3 randomized groups: in-person therapist-led, Internet therapist-led, and a control group. There was no difference in weight loss, percentage of weeks that self-monitoring data were submitted, attrition, or number of peer contacts made in the therapist-led and Internet groups during maintenance conditions. Only 9% of therapist-led participants indicated in a survey done to assess the acceptability of the maintenance protocol that they would have preferred the Internet group, whereas 66% of Internet therapist-led group participants were undecided on satisfaction with their group assignment. These findings suggest that Internet-based weight maintenance programs may be as effective as in-person programs but less appealing to some participants.
In another approach to weight loss maintenance using the Internet,29 122 participants who completed a 6-month behavioral in-person weight control intervention were randomly assigned to one of three 12-month maintenance groups: a frequent in-person support group (F-IPS), a minimal in-person support group (M-IPS), or an Internet support group (IS). The F-IPS and IS groups attended biweekly meetings in person and online, respectively, and submitted self-monitoring records. During maintenance, the Internet group gained more weight and earlier than did the M-IPS and F-IPS groups with in-person support and sustained a significantly smaller weight loss (-5.7 ± 5.9 kg vs -10.4 ± 9.3 kg vs -10.4 ± 6.3 kg; P < .05) at the conclusion of the maintenance program. No significant difference was found in attendance between the 3 groups during the first 6 months of maintenance, but a difference in attendance was significant for the F-IPS and IS groups (54% vs 39%; P = .04) during the second 6 months. Attendance alone cannot explain the difference in weight gain because the M-IPS had no required encounters during the second 6 months of maintenance. The authors suggested that maintenance of weight loss was not related to intensity of contact but to face-to-face contact. At the conclusion of the study, 70% of the IS group stated that they would have preferred to be in a group that met in person. Despite the convenience of the Internet and supposed removal of barriers caused by shame or guilt, the investigators speculated that online sessions negatively impacted communication for participants with group members and therapists.
In the third study of Internet-based weight loss maintenance,30 a 6-month behavioral weight loss program conducted in person using interactive television was followed by a 12-month maintenance program, with 250 participants randomly assigned to 3 groups: frequent in-person support (F-IPS), minimal in-person support (M-IPS), and Internet support (IS).30 During maintenance, the F-IPS group met biweekly in person, submitted self-monitoring records to the therapist team, and participated in therapist-led discussions. The IS group attended biweekly online meetings, submitted self-monitoring data on dietary intake and activity, and participated in online discussions facilitated by the group therapist. Participants in the M-IPS treatment attended monthly in-person meetings over interactive television for the first 6 months of maintenance but had no contact from months 7 to 12. There were no differences among the 3 groups in weight loss during the initial 24-week weight loss treatment or in the percentage of participants who sustained at least a 5% loss of initial body weight at the end of the study at 18 months (IS, 62%; F-IPS, 46%; M-IPS, 49%). As in previous studies, there was a positive correlation between weight loss from baseline to 18 months and attendance (r = 0.26; P < .01) and self-monitoring (r = 0.33; P < .01). A comparison of the IS and F-IPS groups showed that the IS group made more peer contacts (27.1 ± 58.2 vs 4.9 ± 17.4; P < .01) and submitted self-monitoring diaries more frequently (18.6 ± 13.2 vs 11.6 ± 13.2; P < .01). Although not statistically significant, attrition was highest in the IS group (IS, 33%; F-IPS, 21%; M-IPS, 20%), suggesting, as in a previous study,28 that Internet-based weight loss maintenance may have limited appeal. An analysis to determine differences between IS participants who withdrew and those who remained found only a difference in education level, with participants with less education more likely to drop out. The reason for this discrepancy was unclear. These results suggest that sustaining contact over a long period of time via the Internet may be part of an effective weight loss maintenance program for a select population.
The studies of Tate et al,23 Tate et al,24 Southard et al,25 and Veverka et al26 suggest that the Internet is at least as successful as traditional face-to-face programs in producing initial weight loss. The reason for the discrepancy in the results of Womble et al21 is unclear. Even though eDiets.com participants had ample opportunities for support and met in person with a psychologist, the Internet may be too easy to ignore. Perhaps, a commercial program, despite any individualization and support it offers, cannot overcome the appearance of being impersonal. The weight loss programs developed for the other studies may have imparted a sense of the study team's personal touch.
Healthcare professionals who seek to help formerly overweight and obese patients sustain the physiological and psychological rewards that accompany maintenance of their weight loss face a difficult challenge. The literature suggests that the more frequent and longer the contact, the more likely weight loss will be maintained. It is not clear that the Internet can solve this dilemma because the weight loss maintenance results from 3 of these studies are equivocal.
Implications for Nursing Practice and Research
The Internet continues to evolve as a method of healthcare delivery. Although the findings from the 5 weight loss studies suggest that the Internet may be no more effective in producing weight loss than are traditional face-to-face weight loss programs, Internet-based programs still have an immediate advantage over in-person programs because of their the time and cost savings.
Losing just 5% to 10% of body weight can positively impact cardiovascular risk factors, which include hypertension, dyslipidemia, and glucose intolerance. Data from the Framingham Offspring Study found that a weight loss of >=2.2 kg (>=5 lb) over 16 years reduces these risk factors by 40% to 50%.31 Tate et al23 reported that >=5% losses of initial body weight could be achieved through an Internet-based weight loss program, particularly one that included behavior therapy.
Most of the studies reviewed reported a positive correlation between Internet session attendance, submission of self-monitoring reports, and weight loss. Although the Internet allows health professionals to reach large numbers of people, this can be a double-edged sword because it is also easier for individuals to avoid contact. Any intervention that can personalize the Internet experience, such as occasional face-to-face encounters with the health professionals who will be facilitating the online communications, may increase attendance. Research has shown the importance of keeping dietary intake records in maintaining weight loss.32 Weekly e-mail and occasional telephone call reminders may increase the number of self-monitoring records submitted.
Comments from study participants indicated that they prefer face-to-face interventions. Frequent Internet contact through e-mails, bulletin boards, and chat sessions should be supplemented with face-to-face contact. Support group members who have a chance to meet in person before communicating online may perceive a more personalized interaction online.
Diet alone typically is not enough to maintain weight loss. Data show that physical activity is an important determinant of long-term weight loss maintenance. The National Weight Control Registry, the largest study of individuals who have successfully maintained a minimum weight loss of 30 lb for at least 1 year, reveals behavioral strategies, which included high levels of physical activity.32 The studies that investigated the use of the Internet in helping individuals to maintain weight loss encouraged increased physical activity, but they did not include a specific exercise component. The American Heart Association's Choose to Move program is a 12-week Internet program for women that promotes a heart-healthy lifestyle with an emphasis on increasing physical activity. Women who completed an evaluation of the program reported that they had significantly increased their physical activity.33 Adding an exercise component to an Internet-based weight loss maintenance program may increase the likelihood of success and should be investigated further.
The participants in these studies ranged in age from 30 to 62 years and included both men and women. However, in totaling subjects from all the reviewed studies, women outnumber men more than 2 to 1 (women = 587, men = 209). Results from the reviewed studies are therefore difficult to generalize to men, and more studies that include larger numbers of men are needed. Program design may play an important role in gender appeal and is worth examining.
Although this review did not consider studies involving participants under age 30, only 2 randomized controlled trials19,20 found in the literature search investigated the role of the Internet in weight loss for children and adolescents, a population that has more exposure to computers and the Internet than do other age groups9 and at the same time faces rising overweight and obesity. The 1999-2002 National Health and Nutrition Examination Survey shows that nearly one third of children aged 6 through 19 are overweight or are at risk for being overweight.1 The Internet as a mode of weight loss intervention may have great appeal for individuals under the age of 30 years, and it warrants further investigation in this population.
Participants in the reviewed studies were predominately white with more than a high school education. These demographics make it difficult to apply findings to other ethnic and socioeconomic groups. Data suggest that the "digital divide" is narrowing, with 72% of all Americans having Internet access, including 65% of those with less than a high school education. Use of the Internet by low-income and elderly Americans also has increased.34 This user increase still does not answer the question whether Internet-based weight loss programs would be acceptable or successful with various ethnic groups or with those with less education. The bigger question is not accessibility but suitability.
Internet-based weight loss programs should be designed so that they are consistent with the user's needs, values, and social and cultural patterns and operate at a level of complexity that is understandable. Following such guidelines will allow researchers to systematically evaluate and determine where difficulties in adoption occur. Individually tailored programs that consider the user's needs, motivations, values, and constraints should improve the chances of success.
Conclusion
The obesity epidemic, with its consequent morbidity, mortality, and financial burden to society and the individual, demands that healthcare professionals develop effective weight loss programs capable of reaching the millions who are overweight and obese. The convenience and size of the audience using the Internet allow healthcare professionals to access and maintain contact with large numbers of individuals in a time-saving and cost-effective manner. Preliminary studies suggest that the Internet may be an adequate vehicle for weight loss intervention and possibly for programs directed at weight loss maintenance. Further randomized trials are necessary to determine the specific modalities that target specific populations. It certainly behooves nursing to investigate the Internet thoroughly as a means to this end, especially because it concerns a problem as serious as that posed by overweight and obesity, not only in American society but also worldwide.
REFERENCES
1. National Center for Health Statistics. National Health and Nutrition Examination Survey. CDC. Available at: http://www.cdc.gov/nchs/nhanes.htm . Accessed March 25, 2005. [Context Link]
2. National Institute of Diabetes & Digestive & Kidney Diseases. Weight-control information network. Statistics related to overweight and obesity. Available at: http://win.niddk.nih.gov/statistics/index.htm . Accessed May 24, 2005. [Context Link]
3. Flegal KM, Graubard BI, Williamson DF, Gail MH. Excess deaths associated with underweight, overweight, and obesity. JAMA. 2005;293(15):1861-1867. [Context Link]
4. American Heart Association. Heart Disease and Stroke Statistics-2005 Update. Dallas: American Heart Association; 2005. [Context Link]
5. Olshansky SJ, Passaro DJ, Hershow RC, et al. A potential decline in life expectancy in the United States in the 21st century. N Engl J Med. 2005;352(11):1138-1145. [Context Link]
6. Foody JM, Pardon C. Women and coronary artery disease. In:Foody JM, ed. Preventive Cardiology: Stategies for the Prevention and Treatment of Coronary Artery Disease. Totowa, NJ: Human Press; 2001:193-219. [Context Link]
7. Miller WC, Koceja DM, Hamilton EJ. A meta-analysis of the past 25 years of weight loss research using diet, exercise or diet plus exercise intervention. Int J Obes Relat Metab Disord. 1997;21(10):941-947. [Context Link]
8. Ayyad C, Andersen T. Long-term efficacy of dietary treatment of obesity: a systematic review of studies published between 1931 and 1999. Obes Rev. 2000;1(2):113-119. [Context Link]
9. Harvey EL, Glenny A-M, Kirk SFL, Summerbell CD. An updated systematic review of interventions to improve health professionals' management of obesity. Obes Rev. 2002;3(1):45-55. [Context Link]
10. Lenhart A, Horrigan J, Rainie L, et al. The ever-shifting Internet population: a new look at Internet access and the digital divide. Pew Reports. April 16, 2003. Available at: http://www.pewinternet.org/reports.asp?page=5 . Accessed June 1, 2005. [Context Link]
11. US Census Bureau. Computer Use and Ownership. Available at: http://www.census.gov/population/www/socdemo/computer.html . Accessed April 14, 2005. [Context Link]
12. Brug J, Campbell M, Van Assema P. The application and impact of computer-generated personalized nutrition education: a review of the literature. Patient Educ Couns. 1999;36(2):145-156. [Context Link]
13. Oenema A, Brug J, Lechner L. Web-based tailored nutrition education: results of a randomized controlled trial. Health Educ Res. 2001;16:647-660. [Context Link]
14. The Henry J. Kaiser Family Foundation. Medicare removes barriers to obesity treatment coverage, officials announce. Kaiser Daily Health Policy Report. July 16, 2004. Available at: http://www.kaisernetwork.org/daily_reports/rep_hpolicy.cfm . Accessed August 1, 2004. [Context Link]
15. Kirk SFL, Harvey EL, McConnon A, et al. A randomised trial of Internet weight control resource: the UK Weight Control Trial. BMC Health Serv Res. 2003;3(1):19. [Context Link]
16. Wylie-Rosett J, Swencionis C, Ginsberg M, et al. Computerized weight loss intervention optimizes staff time: the clinical and cost results of a controlled clinical trial in a managed care setting. J Am Diet Assoc. 2001;101(10):1155-1162. [Context Link]
17. Glasgow RE, Boles SM, McKay G, Feil EG, Barrera M Jr. The D-Net diabetes self management program: long-term implementation, outcomes, and generalization results. Prev Med. 2003;36(4):410-419. [Context Link]
18. McCoy MR, Couch D, Duncan ND, Lynch GS. Evaluating an Internet weight loss program for diabetes prevention. Health Promot Int. 2005;20(3):221-228. [Context Link]
19. White MA, Martin PD, Newton RL, et al. Mediators of weight loss in a family-based intervention presented over the Internet. Obes Res. 2004;12(7):1050-1059. [Context Link]
20. Frenn M, Malin S, Brown RL, et al. Changing the tide: an Internet/video exercise and low-fat diet intervention with middle-school students. Appl Nurs Res. 2005;18(1):13-21. [Context Link]
21. Womble LG, Wadden TA, McGuckin BG, Sargent SL, Rothman RA, Krauthamer-Ewing ES. A randomized controlled trial of a commercial interest weight loss program. Obes Res. 2004;12:1011-1018. [Context Link]
22. Brownell KD. The LEARN Program for Weight Management 2000. Dallas: American Health Publishing; 2000. [Context Link]
23. Tate DF, Wing RR, Winett RA. Using Internet technology to deliver a behavioral weight loss program. JAMA. 2001;285(9):1172-1177. [Context Link]
24. Tate DF, Jackvony EH, Wing RR. Effects of Internet behavioral counseling on weight loss in adults at risk for type 2 diabetes: a randomized trial. JAMA. April 2003;289(14):1833-1836. [Context Link]
25. Southard BH, Southard DR, Nuckolls J. Clinical trial of an Internet-based case management system for secondary prevention of heart disease. J Cardiopulm Rehabil. 2003;235:341-348. [Context Link]
26. Veverka DV, Anderson J, Auld GW, Coulter GR, Kennedy C, Chapman PL. Use of the stages of change model in improving nutrition and exercise habits in enlisted Air Force men. Mil Med. 2003;168(5):373-379. [Context Link]
27. Brownell KD, Rodin J. The Weight Maintenance Survival Guide. Dallas: American Health Publishing; 1990. [Context Link]
28. Harvey-Berino J, Pintauro SJ, Gold EC. The feasibility of using Internet support for the maintenance of weight loss. Behav Modif. 2002;261:103-116. [Context Link]
29. Harvey-Berino J, Pintauro S, Buzzell P, et al. Does using the Internet facilitate the maintenance of weight loss? Int J Obes Relat Metab Disord. 2002;26(9):1254-1260. [Context Link]
30. Harvey-Berino J, Pintauro S, Buzzell P, Gold EC. Effect of Internet support on the long-term maintenance of weight loss. Obes Res. 2004;122:320-329. [Context Link]
31. Wilson PW, Kannel WB, Silbershatz H, D'Agostino R. Clustering of metabolic factors and coronary artery disease. Arch Intern Med. 1999;159(10):1104-1109. [Context Link]
32. Wing RR, Hill JO. Successful weight loss maintenance. Annu Rev Nutr. 2001;21:323-341. [Context Link]
33. Koffman DM, Bazzarre T, Mosca L, Redberg R, Schmid T, Wattigney WA. An evaluation of Choose to Move 1999; an American Heart Association physical program for women. Arch Intern Med. 2001;161(18):2193-2199. [Context Link]
34. Lebo H. The UCLA Internet Report 2001: Surveying the Digital Future, Year Two. Los Angeles: UCLA; November 2001. Available at: http://www.ccp.ucla.edu/pdf/UCLA-Internet-Report-2001.pdf . Accessed March 28, 2004. [Context Link]