Developmental pathways and programming of diabetes: epidemiological aspects

Type 2 diabetes (T2D) is a major, rapidly increasing global public health challenge. The major risk factors for T2D include overweight and obesity, lifestyle-related factors and genetic factors. Early life exposures shape the developmental trajectories and alter susceptibility to T2D. Based on epidemiological studies it has been suggested that fetal undernutrition plays a role in the etiology of T2D. A low birth weight has been considered a proxy for fetal undernutrition. A meta-analysis reported that a 1 kg increase in birth weight is associated with a roughly 20% lower risk of T2D. Although fetal life is of major importance for future health, the period spanning the first 1000 days of life, is characterized by great plasticity and largely influencing later health. Different growth trajectories during this time period have also been associated with an increased risk of T2D. Studies assessing the association between age at BMI rebound in childhood and later risk for T2D have reported a fivefold difference in T2D according to age at BMI rebound. Developmental and epidemiological cohort studies focusing on T2D have major public health implications supporting a paradigm shift; a shift from focusing upon risk factor modification in adult life to adopting a life course perspective when studying T2D. This paradigm shift will not only help us in getting a better understanding of the pathophysiology underlying T2D, but it will also open new possibilities and opportunities in the prevention of T2D and related disorders.