Differential effects of sucrose, fructose, glucose, and lactose on crying in 1- to 3-day-old human infants: Qualitative and quantitative considerations.

This study assessed the potency of different sugars as calming agents in human infants. Five 0.1-ml aliquots of 0.51 M sucrose, fructose, glucose, or lactose were presented to 1- to 3-day-old infants who were crying spontaneously. Sucrose and fructose were equally effective calming agents, glucose slightly less so. Lactose, the milk sugar, was not at all effective and did not reduce crying any more than did water. In fact, some babies cried more when given lactose. A second experiment established quantitative, dose-response functions for sucrose as a calming agent: 0.17 M, 0.42 M, and 0.51 M sucrose reduced crying equally effectively