Table 2.
Overview of the 40 studies included in the review (36 publications) with data on potential covariates (participant awareness of study purpose, type of portion size offered (self-selected vs. fixed) and presence of other strategies used alongside portion size modification). All studies were carried out in adults except when otherwise indicated under “Tool and control”. The term calibrated is used to describe a portion control utensil with either printed indicators or indented segments (3D). Overall impact of tool is coded as follows: Green—beneficial impact of the small or intervention tool; Orange—relative impact; No color—insufficient evidence or no impact shown. Abbreviations: CHO, carbohydrate; FV, fruit and vegetables; PRO, protein; PS, portion size. Study outcome A, Portion size awareness; C, Portion size choice; I, Portion size intake; W, Weight status.
| Tool and Control | Study Outcome | Duration of Intervention | Participant´s Awareness of Study Purpose | Type of PS | Other Strategy Used Alongside Intervention | Overall Impact of the Tool | Reference |
|---|---|---|---|---|---|---|---|
| NON-TABLEWARE | |||||||
| EDUCATIONAL AIDS AND MEASURING UTENSILS | |||||||
| Tool set (food scales, measuring cups/spoons, placemat with image of plate depicting recommended PS, reference object PS cards). Control: Standard care |
A, I, W | 12 months (free-living) | Aware | Self-selected | Yes—Part of a portion control intervention (Portion-Control Strategies Trial) | Relative impact: NO—body weight YES—dietary energy density |
Rolls et al. 2017 [12] |
| COMPUTERIZED TOOLS | |||||||
|
ServARpreg application for mobile phone Control: No tool |
A | 2 weeks | Aware | N/A (training tool) | No | Relative impact: NO—PS knowledge YES—CHO content estimation |
Brown et al. 2019 [57] |
|
PortionSize@warenessTool, on-line programme No control (before and after) |
A, I, W | 9 months | Aware | Self-selected | Yes—Part of a portion control intervention (SMARTsize) | YES—portion control behaviour (3 months); BMI (9 months) |
Kroeze et al. 2018 [64] |
|
PortionSize@warenessTool, on-line programme No control (before and after) |
A | Acute study | Aware | Self-selected | Yes—Part of a portion control intervention (PortionControl@ HOME) |
YES | Poelman et al. 2013 [65] |
|
PortionSize@warenessTool), on-line programme No control (before and after) |
A, I, W | 12 months (free-living) | Aware | Self-selected | Yes—Part of a portion control intervention (PortionControl@ HOME) |
YES (3 months) | Poelman et al. 2015 [66] |
|
Food Portion Tutorial computer programme, two comparisons: (a) No training vs. training (immediately before meal); (b) No training vs. training (delayed) |
A, I | Acute study | Aware | N/A (training tool) | No | NO | Riley et al. 2007 [67] |
|
ServAR application for tablet vs. Verbal information on recommended PS, vs. Control: No tool |
C | Acute study | Aware | Self-selected | No | YES | Rollo et al. 2017 [68] |
| TABLEWARE | |||||||
| DIFFERENTLY SIZED TABLEWARE | |||||||
| Bowls | |||||||
| Small vs. standard size bowl | I, W | 3 months (free-living) | Aware | Self-selected | No | YES | Ahn et al. 2010 [53] |
| Small vs. large bowl | C,I | Acute study (lab setting) | Unaware | Self-selected | No | NO | Robinson et al. 2015 [27] |
| Small vs. Large bowl Small rice portion size vs. large rice portion size |
I | Acute study (lunch in a classroom) | Unaware (cover story used) |
Fixed and self selected (refills) | Yes —rice portion size (small vs. large) | NO | Shimpo and Akamatsu 2018 [45] |
| Large vs. small cereal bowl (6–12 years old) | C | Acute study (schools) | Not reported/ insufficient information |
Self-selected | No | YES | Van Ittersum and Wansink 2013 [48] |
| Small vs. large bowl (pre-school children) | C, I | Acute study (schools) | Unaware-not clear (with the researcher) | Self-selected | No | YES | Wansink et al. 2014 (Study 1) [49] |
| Large vs. small bowl (6–12 years old, deprived families) | C,I | Acute study (summer camp) | Unaware | Self-selected | No | YES | Wanskink et al. 2014 (Study 2) [49] |
| Cutlery and serving utensils | |||||||
| Serving teaspoon vs. serving tablespoon (4–6 years old, ethnically diverse, some deprived) | C,I | Acute (lab setting) |
Unaware | Self-selected | Yes—amount of entrée available | YES | Fisher et al. 2013 [46] |
| Small vs. large fork | I | Acute study (restaurant) | Not reported/ insufficient information |
Fixed | No | NO (reverse effect detected i.e., those given small fork ate more) | Mishra et al. 2012 [69] |
| Small vs. large fork | I | Acute study (lab setting) | Not reported/ insufficient information |
Fixed | No | YES | Mishra et al. 2012 [69] |
| Small vs. large spoon | C, I | Acute study | Unaware (cover story used) |
Self-selected | Yes—tea served hot or cold as part of an additional research question | YES | Venema et al. 2020 [70] |
| Small vs. medium-size serving bowl | C, I | Acute study | Not reported/ insufficient information |
Self-selected | No | YES | Van Kleef et al. 2012 [60] |
| Glasses | |||||||
| Five glass sizes (250 mL,300, 370 mL (350 in restaurants), 450 mL and 510 mL | I | Mega-analyis of 8 acute studies (5 bars and restaurants) |
Unaware | Fixed | No | Relative impact: NO—bars YES—restaurant (370 mL glass increased sales vs. 300 mL) |
Pilling et al. 2020 [44] |
| Plates | |||||||
| Small vs. medium-size vs. large plate | I | Acute study |
Unaware (cover story used) | Self-selected | No | NO | Ayaz et al. 2016 [54] |
| Small vs. large plate | I | Acute study | Unaware (cover story used) | Self-selected | No | NO | Kosite et al. 2019 [71] |
| Small vs. medium-size vs. large plate | I | Acute study | Unaware (only 1 subject guessed) |
Self-selected | No | NO | Rolls et al. 2007 (Study 1) [72] |
| Small vs. medium-size vs. large plate | I | Acute study (personal buffet) | Aware (55% of subjects guessed) |
Self-selected | No | NO | Rolls et al. 2007 (Study 3) [72] |
| Small vs. large plate | I | Acute study | Unaware (blinded) | Self-selected | No | NO | Shah et al. 2011 [55] |
| Small vs. large plate | C, I | Acute study (all-you can eat Chinese buffet) | Unaware | Self-selected | No | YES | Wansink and Van Ittersum 2013 (Study 2) [62] |
| Small vs. large plate | C | Acute study (health conference buffet) | Unaware | Self-selected | No | YES | Wansink and Van Ittersum 2013 (Study 3) [62] |
| Small vs. large plate | I | Acute study (palatable buffet) | Aware | Self-selected | No | NO | Yip et al. 2013 [56] |
| Tool combinations | |||||||
| Child-sized vs. adult tableware (plate and bowl); (4–5 years old) | C, I | ~1 week | Not reported/ insufficient information |
Self-selected | No | YES | DiSantis et al. 2013 [50] |
| Small vs. large plate with either a shared serving bowl or an individual serving bowl | C, I | Acute study | Unaware (cover story used) | Self-selected | Yes—meal eaten with a friend or stranger as part of an addition research question | YES | Koh and Pliner, 2009 (Study 4) [52] |
| Large vs. standard size tableware (dinner plate, bowl) with side plate | C | Acute study | Not reported/ insufficient information |
Self-selected | No | Relative impact: NO—energy intake YES—larger vegetable PS |
Libotte et al. 2014 [73] |
| Medium-size plate with standard size spoon vs. large plate with large spoon (50% more vs. standard size) | I | Acute study | Unaware | Fixed | No | NO | Rolls et al. 2007 (Study 2) [72] |
| Small vs. large bowl with small vs. large ice-cream scoop | C, I | Acute study (Nutritionists social event) |
Unaware | Self-selected | No | YES | Wansink et al. 2006 [61] |
| Small vs. large tableware (plate, spoon and fork); both served with 120 mL glass | I | Acute study | Not reported | Self-selected | No | Relative impact: NO—total energy YES—rice PS reduction |
Vakili et al. 2019 [63] |
| PORTION CONTROL/CALIBRATED TABLEWARE | |||||||
| Portion control Plates | |||||||
| Calibrated plate (glass with print) with tele-coaching vs. no plate and standard advice (leaflets) | I, W | 6 months (free-living) (Mayo Clinic) |
Aware | Self-selected | Yes—tele-coaching present | YES (3 months) |
Huber et al. 2015 [74] |
| Calibrated plate with 5 sectors (printed) for Rice, PROT and 3 types of vegetables, vs. standard care | C, W | 3 months (free-living) | Aware | Self-selected | Yes—given alongside standard care for CVD | YES (3 months) | Jayawardena et al. 2019 [58] |
| 3D plate with indented sectors for CHO, PROT and FV vs. regular plate | C | Acute study | Aware | Self-selected | No | YES | Hughes et al. 2017 [75] |
| Calibrated tool combinations | |||||||
| Calibrated DietPlate plate plus bowl vs. no tableware (both groups received nutritional counseling) (8–16 y olds) | I, W | 6 months (free-living) | Aware | Self-selected | Yes—part of FOCUS family intervention programme | NO | Ho et al. 2016 [51] |
| Calibrated glass plate and bowl with print vs. standard care | I, W | 6 months (free-living) (Mayo Clinic) |
Aware | Self-selected | Yes —food poster and nutrition advice customized | YES (3 months) | Kesman et al. 2011 [76] |
| Calibrated DietPlate plate plus bowl and book vs. standard care (dietitian contact at start and then as needed) | I, W | 6 months (free-living) (private clinic) |
Aware | Self-selected | Yes—Part of a portion control intervention receiving follow-ups by dietitians and required to complete a daily log | YES | Pedersen et al. 2007 [59] |
| Calibrated plate, bowl and glass (Precise Portions) or portion control serving spoons (Healthy Steps) calibrated protein, carb and veggie ladles/spatula). No control (before and after) |
A | 2 weeks each tool (free-living) | Aware | Self-selected | No | Relative impact: NO—glass YES—plate, bowl, serving spoons |
Almiron-Roig et al. 2016 [77]; 2019 [78] |