A 54-month evaluation of a popular very low calorie diet program

Journal of Family Practice, Sept, 1995 by Michael F. Walsh, Thomas J. Flynn

When the participants entered the program, it was advertised that 85% would lose 18.2 kg and that 60% would maintain the lower weight they achieved.[20] This amount was lost by 59.6% of the patients and maintained by 11%.

Admission BMI classified 2.8% of patients as mildly obese, 34.3% as moderately obese, and 62.2% as severely obese. At the 54-month follow-up, these percentages were 10.5%, 28.7%, and 54.5%. Nonobese weight was maintained by 6.3%. These differences are significantly different (P<.001).

When overweight individuals lose 10% of their body weight, health benefits occur.21 This medically significant weight loss was achieved by 90% of participants and maintained by 26% at 54 months.

Predictors of Maintenance and Reported

Patient Satisfaction

Exercise was associated with improved weight maintenance. Among those who stated at the 54-month follow-up that they exercised regularly, the average weekly exercise reportedly lasted 90 minutes. The initial weight loss at program termination for those exercising was 20.3[ or -]8.9 kg and for nonexercisers, 21.8[ or -]11 kg. The exercisers maintained a 54-month weight loss of 9.6[ or -]14.8 kg. The nonexercisers maintained 1.3[ or -]14.3 kg at 54 months. This positive effect of exercise was significant (P<.001).

After leaving this program, 52 patients (36%) tried other weight-loss programs. These programs included self-help (n=20), VLCD (n=23), over-the-counter weight-loss aids (n=3), multiple (n=2), gastric surgery (n=1), and unspecified (n=4). Patients attending other weight reduction programs reported an average weight of 100.7[ or -]20.3 kg, while those not attending other programs reported an average weight of 100.8[ or -]24.1 kg. There was no significant difference between these groups in reported weight at 54 months.

Patients were asked whether the program helped their sense of well-being. At 54 months, 41.7% reported a positive effect, 35.4% were negative, and 22.9% were neutral.

Discussion

The National Institutes of Health recently convened a second conference to evaluate the available methods of weight loss and control.[9] The incidence of obesity is increasing and now affects almost one third of all Americans. The panel members called for more data on all aspects of obesity, including evaluations of the long-term results of various methods for weight loss.

Very low calorie diet programs should be scrutinized for long-term efficacy, as they are expensive and may be dangerous if not used in a responsible manner.[12,13] The cost of the initial weight loss for these patients was $120.43 for each kilogram, and at 30 months, $395.73 for each kilogram maintained. The estimated cost at 54 months for the 143 patients is $630 for each kilogram of weight loss maintained. Short-term data on patients completing VLCD programs demonstrate initial weight loss of 15 kg to 32 kg and 0% to 78% weight loss maintenance at 18 months.[13,15,22] Results are markedly different when patients are evaluated 2 years or more after program completion, when weight loss maintenance of 0% to 48% is found.[23-28] Most Studies suffer from small study populations, lack of uniform data collection, low percentage of follow-up, or failure to evaluate consecutive patients.[13] With the exception of a 47% follow-up rate, this study does not suffer from these limitations.