First, toddlers eat less because their rate of growth slows. Third, very young children often binge on one food at a time. They may eat a lot of veggies one day, then not touch them for another three days while they overdose on fruit. Between ages 1 and 3, toddlers need between 1,100 and 1,300 calories daily, but they may not eat this amount every single day. That's why you should shoot for a balanced week rather than a balanced meal.
Toddlers like to graze on nutritious nibbles throughout the day.
In fact, eating a number of mini-meals is more physiologically correct than eating three big meals. Use an ice cube tray or a muffin tin and put bite-sized portions of nutritious foods in each compartment. Require him to sit and eat rather than carry food around the house. Toddlers love to dip, so reserve a couple of compartments in the nibble tray for nutritious dips. Many busy toddlers would rather drink their meals than eat them.