Effects of calorie labelling on macro- and micro-nutrients in main-meal choices made by young adults

Abstract

Background/objectives: There is limited evidence that prominent calorie labelling on out-of-home meals helps consumers reduce calorie intakes and avoid weight gain, but no evidence on its effects on macro- and micro-nutrients. The objective of this study was to assess the impact of prominent calorie labelling on energy, macro- and micro-nutrients.

Subjects/methods: Young adults in a catered residential setting were observed when choosing main meals over three study periods in fixed order in this observational study. Period 1: with calorie labels (20 weeks); period 2: without calorie labels (10 weeks); period 3: with calorie labels plus information on estimated energy requirements (10 weeks). Nutrient contents of meal choices were analysed from food composition tables.

Results: Energy, 4 macronutrients and 19 micronutrients levels were derived from 4200 meals chosen by 120 subjects over 40 weeks. Means (s.d. or Median) for key macro- and micro-nutrients were for period 1: energy=658 (94) kcal, fat=31 (8.6) g, saturated fat=10.5 (2.7) g, B12=2.5 (1.7) μg, folate=119 (46.8) μg, vitamin C=80.0 (42) mg, Ca=278 (129) mg, Na=1230 (119) mg, Fe=22 (10) g, Se=19 (10.1) μg, I=34 (10.1) μg, period 2: energy=723 (87) kcal, fat=35 (7.6) g, saturated fat=12 (2.7) g, B12=3.4 (1.7) μg, Folate=182 (13.3) μg, vitamin C=87.0 (49.7) mg, Ca=379 (149) mg, Na=1352 (114) mg, Fe=41.6 (14) g, Se=26 (10.3) μg, I=38.0 (18.4) μg, period 3: energy=578 (109) kcal, fat=27.3 (9.1) g, saturated fat=8.5 (2.7) g, B12=2.2 (0.5) μg, Folate=90 (50.8) μg, vitamin C=75.0 (34) mg, Ca=277 (119) mg, Na=1205 (99) mg, Fe=14.5 (10.9) g, Se=15.0 (10) μg, I=32.0 (18.4) μg. All macro- and micro-nutrients, except for B1, vitamin C, vitamin E and Ca were significantly different between the three periods (P<0.001), but all mean intakes remained above recommended levels.

Conclusions: Calorie labelling resulted in reductions in calories, fat and saturated fat contents of the meals chosen, without compromising micronutrient consumptions.