Being a fat mother doesn’t necessarily mean your children will be overweight too, scientists say
- Academics have argued that whether a child is fat or thin may be down to genes
- But now scientists say lifestyle and diet are more important factors in weight
- Almost one in ten teenagers in the UK are obese, according to official figures
Being born to an overweight mother is not an excuse for being fat in your teens, a study suggests.
Academics have argued for years about whether being chubby or thin as a child is determined by diet or inherited genes.
One leading theory was that mothers with excess bodyfat during pregnancy were more likely to have children who grow up to be overweight.
But British researchers have found there is ‘no strong association’ between the BMI of teenagers and their mothers.
They said other factors — such as diet and lifestyle — were the most important for determining a teenager’s weight.
Imperial College London and Bristol University looked at 9,000 mother and offspring pairs.
There was, however, a ‘moderate’ link between body weight of mothers and children under the age of four.
The researchers said that having fatter babies may be due to foetal over-nutrition — when overreating by the mother results in too many nutrients being passed to the foetus.
Having a fat mother is not an excuse for being overweight in your teens, a study suggests. (stock image)
Almost one in ten teenagers in the UK are obese, figures suggest, while more than a third are overweight. In the US about one in five children are either overweight or obese.
The paper, published in BMC Medicine, looked at mothers and their children between 1992 and 2010.
Childhood obesity hits record high during Covid
Childhood obesity rates in England soared to record levels in the pandemic, official figures show.
One in seven youngsters are obese by the time they start Reception now, compared to one in 10 before Covid struck.
By the time they get to Year 6, the proportion who are too fat rises to one in four, up from one in five in 2019.
The NHS Digital data also shows children from the poorest areas are twice as likely to be obese as those from the least deprived parts.
Obesity campaign groups called the figures ‘alarming’, warning that lockdowns and school closures had taken a huge toll on youngsters’ physical health and widened health inequalities.
More than 2.5million children in England are either overweight or obese and experts fear they are on course to become the fattest generation in history.
Women were monitored either shortly before falling pregnant or when they were already carrying a child.
Children had their BMI — or body mass index — looked at in two age brackets, between the ages of one and four, as well as 10 to 15.
Women were 28 years old on average, and one group had a BMI of 23 — putting them inside the healthy range.
A second group had a BMI of about 26 — classing them as overweight.
About five per cent of mothers included in the study were obese during pregnancy, defined as a BMI above 30.
Previous research has linked being fat during pregnancy to having children who also go on to be overweight.
But in their latest study, the researchers found only a ‘small to moderate link’ — and only in babies and toddlers.
But after the age of four the link starts to diminish and by their teenage years there is no link at all.
They say complex genetic factors, foetal overnutrition and overfeeding could all be playing a role in such young children.
Lead author and epidemiologist at Bristol University, Dr Tom Bond, said: ‘We found that if women are heavier at the start of pregnancy this isn’t a strong cause of their children being heavier as teenagers.
‘This is important to know. Supporting women and men at all ages to keep a healthy weight will be needed to prevent obesity.’
He added: ‘It isn’t enough to just focus on women entering pregnancy. So prospective mothers should still be encouraged and supported to maintain a healthy weight.’
Despite the results, the researchers are encouraging women to achieve a healthy weight before conceiving.
Being overweight or obese is dangerous for both woman and child, and can lead to high blood pressure, blood clots and diabetes in the mother.
It also raises the risk of a premature birth and other complications.