Portion size can be used strategically to increase vegetable consumption in adults

Area of Science:

• Nutrition science
• Dietary interventions
• Weight management

Background:

• Increasing vegetable consumption is crucial for meeting dietary recommendations.
• Vegetables play a key role in weight management strategies.
• Understanding how to optimize vegetable intake is important for public health.

Purpose of the Study:

• To examine the impact of vegetable portion size and energy density on food and energy consumption.
• To compare the effects of adding versus substituting vegetables in meals.
• To determine the most effective strategies for increasing vegetable intake while managing energy intake.

Main Methods:

• Two crossover studies were conducted with adult participants.
• Vegetable portion sizes (180, 270, 360g) and energy densities (0.8, 0.4 kcal/g) were manipulated.
• Food and energy intakes were measured in both 'addition' and 'substitution' scenarios.

Main Results:

• Increased vegetable portion size led to higher vegetable consumption.
• Substituting vegetables for other foods significantly decreased meal energy intake.
• Lowering vegetable energy density reduced meal energy intake, independent of portion size.
• Combining substitution with reduced energy density lowered meal energy intake by 14%.

Conclusions:

• Serving more vegetables, via addition or substitution, increases vegetable intake.
• Low energy density is key for vegetables to moderate energy intake.
• Substituting vegetables for energy-dense foods is more effective for reducing energy intake than simply adding more vegetables.