How Babies Grow: What is a Healthy Weight?

The challenge

We’re all different shapes and sizes and that’s how it should be, but being a healthy weight is really important – especially in childhood because we know that children who are overweight are more likely to be overweight as adults. Also, being a healthy weight reduces our risk of developing heart disease and diabetes in the future. How big or small we are is partly inherited from our parents but it also depends on how we live our lives. In Born in Bradford we want to know more about how and why we all grow differently, how that can make a difference to our future and what we can do to stay healthy

What we are doing about it

In BiB we have been measuring children since they were born. We have measured their height, weight and skinfold thickness. Skinfold thickness is measured to help us estimate how much body fat we have. We have also collected blood pressure measurements from the children at age 4-5. So far, we have seen differences in size, growth and body fat between children of South Asian origin and children of White British origin. South Asian babies were smaller and lighter at birth but we found that they grew quicker in infancy so that by age 2 they had a similar weight to White British children. Although the White British babies were bigger and heavier when they were born, they had less fat than South Asian origin babies. We are still looking into the reasons for these differences and how important they might be to the health and development of children in the future

Our future plans

In the next phase of the study, with the support of BiB parents and schools, we want to repeat some of the measurements we took when the children were born and when they started their first year at school. This time we are also using a test that estimates how much fat and lean tissue each person has. We want to learn how this can affect weight and growth. We will put this information about height, weight and body fat alongside other things that might make a difference to how children grow, such as: family history, how active they are and what they eat. All these things could be important in understanding what a healthy weight is, and how this contributes to a healthy life.

Link to full research

You can read more on this research in the following papers:

• West, J., Lawlor, D. A., Fairley, L., Bhopal, R., Cameron, N., McKinney, P. A., et al. (2013). UK-born Pakistani-origin infants are relatively more adipose than white British infants: findings from 8704 mother-offspring pairs in the Born-in-Bradford prospective birth cohort. Journal of epidemiology and community health, 67(7), 544-551. here
• West, J., Wright, J., Fairley, L., Sattar, N., Whincup, P., & Lawlor, D. A. (2013). Do ethnic differences in cord blood leptin levels differ by birthweight category? Findings from the Born in Bradford cohort study. International journal of epidemiology. here
• Fairley, L., Petherick, E. S., Howe, L. D., Tilling, K., Cameron, N., Lawlor, D. A., et al. (2013). Describing differences in weight and length growth trajectories between white and Pakistani infants in the UK: analysis of the Born in Bradford birth cohort study using multilevel linear spline models. Archives of disease in childhood, 98(4), 274-279. here