Plate size affects how much food we serve and consume. Larger plates (modern 12-inch dinner plates) lead to larger portions and more consumption. Smaller plates (10-inch) produce smaller portions that feel equally satisfying.
What the research shows
Same food on different plate sizes is perceived as different portion. Smaller plate feels 'full', larger plate feels 'half-empty' — and people serve themselves accordingly.
How to apply
Use side plates or salad plates as your dinner plates. Original-size dinner plates (10 inches) from older sets. Avoid the 12-inch modern plates that drive portion creep.
Most users find they eat less without conscious restriction by using smaller plates. The visual signal works without requiring willpower.