The 1,000 days that can change your child’s fat(e)

A combination of “fat genes” and growing up in an environment that promotes weight gain can predispose a child to obesity – especially in the first 1,000 days (conception to two years of age) of life. However, our newest research shows that even children born at high risk for developing adiposity can beat the odds and grow up healthy.
By Anna Fogel

Feeding a child

Through the years, it’s been observed that obesity runs in families. Commonly referred to as “fat genes”, this predisposition (pre)determines our body shape in the early months of life. Another factor that often goes hand in hand with a predisposition to adiposity is the “obesogenic environment”, which refers to an environment that promotes unhealthy weight gain.

The higher the number of such unfavourable factors during the first 1,000 days of life, the higher the likelihood of developing obesity in one’s later years. But is obesity really inevitable for those who are supposedly predisposed to it? Our latest research shows that even children born at high risk for developing obesity can beat the odds and grow up healthy.

What is the first 1,000 days and why does it matter?
The first 1,000 days is the period from the beginning of pregnancy until the child's second birthday. This period is sometimes referred to as the ‘golden window’ as it is the most sensitive time in a baby’s life, characterised by dramatic physical, mental and developmental changes. Various familial and environmental factors during the first 1,000 days can have long-term negative (or positive!) influences on growth and development. Unfavourable conditions in the first 1,000 days strongly influence a child’s likelihood to develop obesity in subsequent years. This is problematic because we know that childhood obesity tracks to adulthood, which means that children with obesity will likely grow up to become obese adults, who then have babies with increased obesity risk, and the cycle continues.

The importance of the ‘golden window’ is supported by data from the local Growing Up in Singapore Towards Healthy Outcomes (GUSTO) cohort. Maternal or paternal overweight, excessive weight gain or high blood glucose levels in pregnancy, and environmental factors occurring after birth like short duration of breastfeeding or introducing solid foods early, all increased children’s risk of developing obesity at six years of age, despite these factors occurring in the first 1,000 days of life.

We also found that not all risk factors are equally influential. Children born to mothers who had pre-pregnancy overweight or a father with overweight, and those who were introduced to solid foods before four months of age, had the highest odds of developing obesity at six years of age. At the same time, children who were exposed to multiple risk factors – particularly those most influential – were 6.5 times more likely to develop obesity at six years of age as compared to those who did not have any risk factors in the first 1,000 days, or only had one or two of the less impactful ones.

But as it turns out, it may be possible to beat the obesity odds.

The next 1,000 days and the importance of eating behaviours
Although the first 1,000 days are undeniably an important period for programming of trajectories of growth, children’s behaviours in the subsequent 1,000 days (essentially early childhood) is equally important. Eating behaviours have been increasingly recognised as a key predictor of children’s weight status.

Findings from the GUSTO cohort show that the size of food portions, the speed with which children consume their meals, the size of the bites they take and the number of chews they take to swallow food are important predictors of their weight. Children who select larger portions of food, who take larger food bites, fewer chews and who finish their meals faster are more likely to overeat and ultimately, are more likely to be obese. But is the reverse also true? Can we prevent the development of obesity by maintaining optimal eating behaviours?

Nurture trumps nature
The way children eat can mitigate their early life risk for developing obesity. In our recent study, we demonstrated that GUSTO children with multiple risk factors for obesity in the first 1,000 days are at a higher risk for developing obesity at six years of age only if they exhibit eating behaviours that promote overeating, such as selecting larger food portions, eating fast and consuming food when they are no longer hungry. Children with multiple risk factors in the first 1,000 days – even with the most influential ones – did not develop obesity at age six when they selected smaller food portions, ate slowly and ate less overall.

Risk factors in the first 1,000 days can be used to identify children who are at higher risk of developing obesity to target those families in intervention programmes focused on promoting eating behaviours that facilitate healthy growth. Teaching children to select appropriate food portions, promoting a slower eating pace, with smaller bites and longer chewing and training the child to terminate eating when no longer hungry can go a long way in mitigating early life risks on future weight gain, and ultimately health. 

These findings show that obesity is not inevitable and that we can beat the odds and develop a healthy weight by promoting and cultivating healthy eating behaviours in the early years of life.

Dr Anna Fogel has a keen interest in behavioural and psychosocial factors pertaining to (un)healthy growth in childhood, and her research is largely focused on individual differences in behavioural susceptibility to obesity in the first years of life – particularly the role of intrinsic and environmental influences on children’s appetite and their expression in the four aspects of eating behaviour (What, How, How much and When children eat). Involved in GUSTO, she’s been investigating modifiable eating behaviours that promote increased energy intakes and obesity in children, with particular focus on oral processing characteristics, portion size preferences, snacking patterns and general dietary habits.