This thesis involved a longitudinal study of 30 healthy infants from 6 weeks to 15 months to investigate the relationship between feeding behaviour and weight gain in infancy. Poor infant weight gain is associated with adverse outcomes in childhood (e.g. Skuse, Pickles, Wolke, et al 1994) and adulthood (e.g. Fall, Vijayakumar, Barker, et al 1995). Previous research has investigated the relationship between feeding behaviour and concurrent weight, but with a few exceptions there has been little previous work on the relationship between feeding behaviour and weight gain in infants. Feeding behaviour was measured at four breastfeeds in 32 infants at six weeks and later in 30 of the same infants at 12 months during solids feeding. Birthweight was obtained from parents' child health records and weight was measured at 6 weeks, 3 months and thereafter every 3 months until 15 months. Sucking patterns during milk feeding were found to be independently associated with infant weight gain, but there was no independent association between solids feeding behaviour and weight gain. Other independent predictors of weight gain were; infant sex, milk intake during breastfeeding and age of introduction of solids. An analysis of associations between milk and solids feeding behaviour found some evidence of parallels within infants across the two different types of feeding and the implications of this are discussed. A new method for the analysis of breastfed infants' sucking patterns which resolves the serious problems of the already published methods was developed during die course of the study and an outline of this is provided. Previously unavailable data on (1) the behaviour of one year olds during solids feeding and (2) the components of variation in milk and solids feeding behaviour are discussed
