Monday, October 2, 2023
| Low-carbohydrate, higher-protein diet use: |
| 1. "Are you currently on or have you ever been on a low-carbohydrate, higher-protein diet such as Sugar Busters, The Zone, The Carbohydrate Addict's Diet, or The Atkins Diet?" Response categories were: "Yes, I am currently on the diet", "Yes, I have been on the diet in the past but am not on it now", "No, I have never been on the diet." |
| 2. "The last time you were on this diet, how long were you on it?" Or, if currently on it, "How long have you been on this diet?" Responses were open-ended. |
| 3. "How much weight have you lost using the diet?" Responses were open-ended. |
| Weight-control product use: |
| "We would like you to tell us about products you have used to try to control your weight -- that is, to lose weight or to prevent weight gain." |
| 1. "Have you ever used any food supplied by a weight loss program or used any special meals such as Weight Watchers, Lean Cuisine, or Healthy Choice to control your weight?" |
| 2. "Have you ever used any meal-replacement shakes or bars to control your weight?" |
| 3. We would like you to tell us about any other products that were NOT prescribed by a doctor that you have taken to control your weight, including over-the-counter products such as pills, powders, and liquids. This includes dietary supplements and natural or herbal weight loss aids not prescribed by a doctor. "Have you ever taken any of these products to control your weight?" |
| 4. "Have you ever used any type of complementary and alternative medicine (CAM) methods or therapies to lose weight, prevent weight gain, or to support your weight control efforts?" |
| Response categories for weight-control product questions 1-4 were, "Yes, in the past 12 months," "Yes, but not in the past 12 months," and "No." |
Survey Questions Used in the National Physical Activity and Weight Loss Survey
| Characteristic | n | % | (se) | OR* | (95% CI) |
|---|---|---|---|---|---|
| Total | 9300 | 3.4 | (0.2) | ||
| Men | 4021 | 3.2 | (0.3) | 1.00 | |
| Women | 5279 | 3.6 | (0.3) | 1.25 | (0.94, 1.65) |
| Age (years) | |||||
| 18-34 | 2544 | 2.1 | (0.4) | 0.57 | (0.38, 0.84) |
| 35-54 | 3849 | 4.0 | (0.4) | 1.00 | |
| ≥ 55 | 2907 | 3.9 | (0.4) | 0.98 | (0.74, 1.31) |
| Race/ethnicity | |||||
| White | 6514 | 3.6 | (0.3) | 1.00 | |
| Black | 1103 | 2.7 | (0.6) | 0.71 | (0.43, 1.18) |
| Hispanic | 1213 | 3.7 | (1.0) | 1.25 | (0.74, 2.09) |
| Other | 470 | 2.2 | (0.7) | 0.65 | (0.34, 1.24) |
| Education | |||||
| Less than high school | 948 | 3.0 | (0.9) | 1.00 | |
| High school or equivalent | 2566 | 3.1 | (0.4) | 1.08 | (0.57, 2.03) |
| Some college | 2570 | 3.2 | (0.4) | 1.19 | (0.63, 2.23) |
| College graduate | 3216 | 4.0 | (0.4) | 1.52 | (0.84, 2.75) |
| Body mass index (kg/m2) | |||||
| < 25.0 | 3896 | 2.6 | (0.3) | 1.00 | |
| 25 - 29.9 | 3395 | 3.8 | (0.4) | 1.52 | (1.08, 2.14) |
| ≥ 30.0 | 2009 | 4.6 | (0.5) | 1.87 | (1.33, 2.63) |
Prevalence and Odds of Currently Being on a Low-Carbohydrate, High-Protein Diet Among Respondents (N = 9300)
OR = odds ratio; CI = confidence interval; se = standard error *Model adjusted for sex, age, race/ethnicity, education level, and current body mass index.
| Currently on an LCHP Diet | Not Currently on an LCHP Diet | P value | |||
|---|---|---|---|---|---|
| (n = 301) | (n = 6259) | ||||
| % | (se) | % | (se) | ||
| Eating strategies to control weight | |||||
| Fewer calories | 21.7 | (2.6) | 15.9 | (0.6) | .0269 |
| Less fat | 9.0 | (1.9) | 13.2 | (0.5) | .0335 |
| Fewer calories and less fat | 48.4 | (3.4) | 48.4 | (0.8) | .9954 |
| Nothing | 20.9 | (2.7) | 22.5 | (0.6) | .5578 |
| Fewer calories* | 70.1 | (3.1) | 63.2 | (0.7) | .0641 |
| Physical activity | |||||
| Inactive | 7.6 | (1.7) | 10.6 | (0.5) | .0784 |
| Insufficient | 38.0 | (3.2) | 36.7 | (0.7) | .7017 |
| Meets recommendations for health** | 51.9 | (3.4) | 47.8 | (0.8) | .2405 |
| Fewer calories* for weight control and meets physical activity recommendations | 38.0 | (3.4) | 29.8 | (0.7) | .0179 |
| Past year use of foods supplied or special meals | 15.8 | (2.3) | 16.6 | (0.6) | .7163 |
| Past year use of meal replacement shakes or bars | 29.5 | (3.1) | 16.7 | (0.6) | < .0001 |
| Past year use of nonprescription weight control products | 23.1 | (2.8) | 13.5 | (0.5) | .0009 |
| Past year CAM weight loss therapies | 5.1 | (1.3) | 4.2 | (0.3) | .5002 |
| History of chronic disease | 39.1 | (3.3) | 29.5 | (0.7) | .0050 |
| Past year medical advice | |||||
| Lose weight | 26.7 | (2.8) | 15.2 | (0.5) | .0001 |
| Maintain weight | 5.3 | (1.5) | 2.7 | (0.2) | .0861 |
| Not given advice | 59.4 | (3.3) | 71.3 | (0.7) | .0004 |
| Did not see physician | 8.1 | (1.9) | 10.3 | (0.5) | .2534 |
| Gain weight | 0.5 | (0.5) | 0.5 | (0.1) | .9372 |
Prevalence of Weight-Control Advice and Approaches, Including Diet and Physical Activity, by Current Low-Carbohydrate, High-Protein (LCHP) Diet Status Among Respondents Trying to Lose or Maintain Their Current Weight (N = 6560)
CAM = complementary and alternative medicine methods or therapies to lose weight *Summation of both weight loss strategy responses, Fewer calories and Fewer calories and less fat **Those meeting minimal physical activity recommendations were defined as those who reported participating in regular moderate activity, defined as 30 or more minutes of moderate nonoccupational physical activity 5 or more times per week, and/or in regular vigorous activity, defined as 20 or more minutes of vigorous physical activity 3 or more times per week.
| Total | Men | Women | P value* | ||||
|---|---|---|---|---|---|---|---|
| (n = 327) | (n = 136) | (n = 191) | |||||
| Weight lost while on an LCHP diet | |||||||
| Mean lb (se) | 18.3 | (1.2) | 19.5 | (1.9) | 17.2 | (1.6) | .3375 |
| Median lb (se) | 11.7 | (1.1) | 14.2 | (1.9) | 10.9 | (1.3) | .1527 |
| No weight lost, % (se) | 8.8 | (1.9) | 10.9 | (3.2) | 6.9 | (2.1) | .2981 |
| Weight loss ≥ 20 lb, % (se) | 34.0 | (3.0) | 40.2 | (4.7) | 28.7 | (3.7) | .0543 |
| Weight loss ≥ 30 lb, % (se) | 18.2 | (2.4) | 21.8 | (3.9) | 15.2 | (3.0) | .1756 |
| Length of time on an LCHP diet | |||||||
| Mean months (se) | 14.7 | (2.0) | 17.9 | (3.6) | 11.9 | (1.8) | .1386 |
| Median months (se) | 3.9 | (0.6) | 5.7 | (1.5) | 2.8 | (0.6) | .0753 |
| ≥ 6 months, % (se) | 49.3 | (3.3) | 59.9 | (4.7) | 39.9 | (4.3) | .0018 |
| ≥ 12 months, % (se) | 35.5 | (3.1) | 42.2 | (4.9) | 29.6 | (3.9) | .0438 |
| ≥ 24 months, % (se) | 12.9 | (2.3) | 14.9 | (3.7) | 11.2 | (2.8) | .4164 |
Reported Weight Lost and Diet Duration Among Current Low-Carbohydrate, High-Protein (LCHP) Diet Users by Sex (N = 327)
se = standard error *Test for sex difference
| LCHP Diet Duration | ||
|---|---|---|
| ≤ 6 months | > 6 months | |
| Total | (n = 202) | (n = 125) |
| Mean months (se) | 13.4 (0.9) | 25.8 (2.7) |
| Median months (se) | 10.0 (1.1) | 18.2 (2.5) |
| Weight loss ≥ 20 lb, % (se) | 23.2 (3.4) | 50.8 (5.1) |
| Men n = 136 | ||
| Mean months (se) | 15.8 (1.5) | 23.7 (3.5) |
| Median months (se) | 14.1 (1.1) | 13.8 (3.5) |
| Weight loss ≥ 20 lb, % (se) | 33.7 (6.2) | 47.5 (7.2) |
| Women n = 191 | ||
| Mean months (se) | 11.7 (1.0) | 28.6 (4.0) |
| Median months (se) | 9.4 (1.2) | 19.0 (3.1) |
| Weight loss ≥ 20 lb, % (se) | 16.0 (3.5) | 54.9 (7.0) |
Reported Weight Lost by Duration on the Diet Among Current Low-Carbohydrate, High-Protein (LCHP) Diet Users
se = standard error
processing....
Context: Although low-carbohydrate, high-protein (LCHP) diets reemerged as popular diets, there are scant data on patterns of use
in the general US population.
Objective: We examined the prevalence of reported LCHP diet use (eg, Sugar Busters, The Zone, The Carbohydrate Addict's Diet, The Atkins
Diet), associated weight control behaviors, diet duration, and amount of weight loss while on the diet.
Design: Population-based cross-sectional survey.
Setting: Telephone survey of US adults conducted from September 2002 to December 2002 (N = 9300).
Main Outcome Measures: We used multivariable logistic regression models to determine predictors of current LCHP diet use.
Results: At the time of the survey, 12.5% of Americans reported ever using a LCHP diet, and 3.4% reported current use. Prevalence of current use was similar across sex, race/ethnicity, and education levels. Among those trying to lose weight (n = 3790), 5.9% reported currently using an LCHP diet. Among current users, mean weight loss was 18.3 (median, 11.7) lb, with 18.2% reporting ≥ 30 lb weight loss, 34.0% ≥ 20 lb weight loss, and 8.8% no weight loss. More men than women reported a duration of use of more than 12 months (42.2% vs 29.6%, P = .04) and median duration was greater in men than women (5.7 vs 2.8 months, P = .08). Among those trying to control weight, a significantly higher proportion of current LCHP diet users reported eating
fewer calories and meeting physical activity recommendations (38.0%) compared with nonusers (29.8%).
Conclusions: LCHP diets were equally prevalent across sociodemographic subgroups and many users reported significant weight loss. Approximately
40% of male users and 30% of female users reported long-term use of the diet, suggesting that for some, this dietary approach
may be well tolerated.
Low-carbohydrate, high-protein (LCHP) diets were first popularized in the 1970s with the publication of Dr. Atkins' Diet Revolution.[1] The popularity of these diets resurged, as reflected in the publication of such books as Sugar Busters,[2]Dr. Atkins' New Diet Revolution,[3] and The South Beach Diet.[4] These books have enjoyed great popularity with millions of copies sold.[5] Although each plan has different recommended foods, exercise advice, and proposed mechanisms, most share common premises regarding protein and refined carbohydrate intake. In the past, health professionals discouraged use of LCHP diets because early versions of these diet plans allowed dieters to consume large amounts of high-fat products and affirmed that physical activity was not an integral part of weight loss.[1] More recent LCHP diet books advise consumption of lean protein sources, allow unrefined carbohydrates including certain fruits and vegetables, and include exercise for improved weight control.[2,4] Most, however, still fail to discuss the association of calories and weight loss.
Despite the widespread popularity of these diets, only recently have the results of randomized trials of LCHP diets become available. The majority of these trials found that LCHP diets led to increased short-term weight loss at 3 and 6 months compared with conventional calorie-restricted low-fat diets.[6-9] However, none of the trials had better weight loss than conventional diets at 12 months.[7-11] Trials also found that use of LCHP diets for 12 months or less was not associated with deleterious effects on risk factors for cardiovascular disease.[6-12] Regardless of the regimen (LCHP or traditional restricted-calorie low-fat diet), clinical trial subjects experienced weight loss primarily because of decreased caloric intake. Many subjects had difficulty in sustaining dietary adherence over time, with high dropout rates in both regimens.[6,11,13]
Although short-term weight loss can be achieved by many diets, sustained behavior change and long-term weight maintenance are far more challenging. LCHP diets are often thought of as fad diets, but there have been scant data from the general population on the amount of time that people stay on a LCHP diet and the amount of weight lost. One purpose of our analysis was to describe the general experience of LCHP dieters outside of the clinical trial setting. Although prevalence of LCHP dieting use may have changed over time, little is known about the characteristics of dieters and whether these dieters use calorie reduction and physical activity as part of their regimen. The purpose of this analysis was to assess data collected in the fall of 2002 from a population-based telephone survey to determine: (1) the prevalence of LCHP dieting by demographic characteristics, and among current LCHP diet users; (2) the prevalence of other weight control behaviors including use of meal-replacement products, herbal weight loss aids, calorie restriction, and physical activity (PA); and (3) length of time on the diet and amount of weight lost.
