: OBJECTIVE: The Barker's hypothesis states that poor nutrition in vitro is linked to low birthweight and major illness, in particular cardiovascular disease, in later life. Reported here is an investigation to establish links with birthweight and minor illness. METHODS: 78 participants whose birthweight ranged from 1.93 kg to 4.88 kg with a mean to 3.31 kg completed a symptom checklist. RESULTS: Analysis of variance indicates that those with a higher birthweight experience less minor illness. Regression analysis indicates that birthweight is significantly predictive of levels of some minor illnesses. CONCLUSION: This investigation adds a new dimension to Barker's hypothesis and shows that early environment can also affect levels of minor illness. It is suggested that susceptibility to minor illness may be explained by coactions between structure, function and environment prior to birth.