Table 2.
Meta-Analyses of Effects of Food Labeling Interventions on Consumer Dietary Behaviors (Continuous Outcomes)a
| Dietary factor | Number of study estimates (individual studies) |
Number of consumers or purchases |
Percent difference with labeling (95% CI)b |
|---|---|---|---|
| Calories | 31 (23) | 43,707 | −6.6 (−8.8. −4.4) |
| Total fat | 13 (12) | 4,409 | −10.6 (−17.7.−3.5) |
| Total carbohydrate | 8 (7) | 1,928 | 2.2 (−5.1, 9.5) |
| Total protein | 6 (5) | 1,110 | 0.6 (−2.8, 4.0) |
| Saturated fat | 5 (5) | 2,227 | −8.4 (−23.7, 6.8) |
| Sodium | 5 (5) | 2,016 | −15.3 (−31.3, 0.7) |
| Vegetables | 5 (5) | 1,497 | 13.5 (2.4.24.6) |
| Fruits | 3 (3) | 1,103 | 10.9 (−16.0, 37.7) |
| Whole grains | 3 (2) | 760 | 14.4 (−11.8, 40.6) |
| Other healthy optionsc | 30 (11) | 2,685 | −0.5 (−2.8, 1.7) |
| Other unhealthy optionsd | 16 (7) | 5,548 | −13.0 (−25.7.−0.2) |
Food labeling (i.e., standardized provision of nutrition or health information) included product package, menu, or other point-of-purchase labeling. Dietary behaviors were evaluated by direct observation (e.g., weighed plate waste) or self-report from single sessions, 24-hour diet recalls, food diaries, or food frequency questionnaires; or as consumer purchases, food outlet sales, or choices/orders as a proxy for consumers’ self-reported dietary intakes. When the same study evaluated both sales/purchase data and consumer intake data, the authors utilized sales/purchase data given its objectivity. Pooled findings prioritizing consumer intake data for these studies were not appreciably different (Appendix Table 12). Appendix Figures 1–18 show individual forest plots and more details on each meta-analysis. Results stratified by consumer intake vs purchases/sales are also available but not shown.
Based on the units reported in the study (e.g., most commonly kcal for calories, gram or percent energy for dietary fats, servings or g/d for foods, etc).
Items recommended by labels to consume, such as salads, soups, low-fat dairy, lean meat, low-fat desserts, fish and seafood, water, diet soda, and foods higher in dietary fiber, vitamin C, and calcium.
Items recommended by labels to avoid, such as sugar-sweetened beverages, alcoholic beverages, non-alcoholic caloric beverages, French fries, potatoes, white bread, and foods higher in saturated fat, trans fat, added sugars or sodium.