There are many different stages in life when obesity can develop and in fact very few individuals evade risk completely. Our vulnerability is increased in a number of situations.

Pregnancy

It is desirable that pregnancy commences at normal weight, and optimal nutrition is vital before conception. Therefore, care needs to be taken to avoid strict over-restrictive diets during this period.

Physiological mechanisms during a healthy pregnancy facilitate a certain degree of weight gain. However, losing this weight after pregnancy proves difficult for many women, especially if they choose not to breastfeed. This may, in part, explain the increased prevalence of obesity among women when compared with men. A new baby brings extra demands that may affect the mother’s ability to follow a regular eating plan or to engage in regular physical activity. Pregnancy (or pre-conception) is not a time for ‘dieting’ but it is appropriate to encourage women to eat healthily and, if possible, avoid excessive weight gain during this time.

Infants and toddlers

There is some evidence that breastfeeding helps prevent obesity in later life.^26–28 The promotion of healthy eating from an early age is also desirable. 

Childhood and adolescence

The number of overweight and obese children in the UK has doubled since the 1980s with 10% of six-year-olds and 16.8% of 15-year-olds now obese.²⁹ Britain has witnessed its first cases of adolescent-onset type 2 diabetes, indicating that the rise in obesity among children is of grave concern. Childhood is a time when eating habits and food preferences are formed. Concerns that focusing on a child’s or teenager’s weight could have a negative psychological impact need to be weighed against the evidence that children of obese parents are at a greater risk of developing the same condition, and that childhood obesity substantially increases the risk of adult obesity.^29–31 Sensible and sensitive approaches to weight management (prevention and treatment) would seem prudent if the next generation are going to avoid the serious consequences of obesity.

Middle age

Statistics show that ‘middle-aged spread’ is not just a turn of phrase. As we age our weight tends to increase, but this is more likely to be due to environmental factors rather than metabolic ones. Aging is associated with a decline in the level of physical activity undertaken and subsequent loss in muscle strength. In women, hormonal changes through the menopause can bring changes in fat distribution.

Retirement

This can also be a somewhat vulnerable time, with many individuals experiencing a loss of structure to their normal eating and activity patterns.

Learning disabilities

There is a higher incidence of overweight and obesity amongst individuals with learning disabilities e.g. Down’s Syndrome.³²