Obesity is an important issue that modern society is facing due to the health problems that it causes to individuals which in avertedly affects society. In this issue of The Medical Journal of Australia, the role of exercise in maintaining health from childhood, adolescence period, and reproductive years were examined.

The importance of exercise and fitness was also emphasized in this research as exercise in itself is a good habit regardless if a person is trying to lose weight or not. Aside from that, the researchers also proposed that exercise and fitness are better in terms of predicting cardiovascular and all-cause mortality as opposed to obesity.

Skouteris and colleagues observe that it does indeed seem to be good to start young. They look at existing guidelines for physical activity in preschoolers (what would our grandmothers have thought of guidelines for preschoolers?), and acknowledge that we really have no idea about appropriate guidance. Guidelines are inconsistent, and their basis uncertain. Furthermore, there is a lack of information about what is a normal level of activity, and a lack of knowledge about what activity (moderate or intense?) should be measured and how to measure it.

Nearly one in four Australian adolescents are overweight or obese, according to Morley and colleagues. Being male, less wealthy, inactive, sleep-deprived and frequently hooked to a computer or TV is characteristic of those at highest risk. The most important factor was found to be low socioeconomic status, but the way this is associated with obesity is still to be ascertained. One thing Rissel and colleagues have confirmed is a significant association between soft drink consumption and obesity in school students.

McIntyre and colleagues argue that overweight and obesity are now endemic in pregnant women. They found that, despite some missing data, the overall prevalence of overweight and obesity had increased little over a decade, but the obese had become more obese. In a large cohort, about one in 20 pregnant women had a BMI of 35 kg/m2 or higher. As with adolescents, obesity was associated with lower socioeconomic status. The authors confirm that being overweight or obese confers significant maternal and neonatal risk, requiring more obstetric resources. From an obstetric point of view, it is challenging to care for people who are this large, and more challenging to safely deliver their babies. Women need to know that obesity, like tobacco and alcohol, is a risk factor in pregnancy.

Despite all the unknowns in our understanding of overweight and obesity, the simple principle of energy in and energy out should underpin much of our thinking. Magarey provides some practical suggestions for redressing the imbalance between food consumption and exercise that is so prevalent in our society. If we want our children to enjoy a long and healthy life, we need to work on this equation.