Health: Obese mothers are 60% more likely to have children who develop mental illness as adults

Children of very obese mothers are significantly more likely to have mental health disorders such as schizophrenia and substance abuse problems as adults, a study finds.

Experts led by the University of Helsinki looked at the relationship between maternal weight and offspring mental health in 68,571 births in Aberdeen from 1950-1999.

They found that adults born to severely obese women in the period 1975-1999 had a 60 percent higher risk of developing some form of mental illness as adults.

However, the researchers also found that underweight mothers were the greater predictor of adult mental illness among the children born in 1950-1974.

For this group in particular, children born to mothers with a BMI of less than 18.5 during pregnancy were 74 percent more likely to develop a mental illness later in life.

The first finding builds on previous studies that have shown that children born to obese and overweight mothers are at greater risk for childhood mental health problems.

Obesity has become more common among pregnant women in recent years, with a prevalence of 7-25 percent in Europe and over 30 percent in the US.

Last year, the UK government set out a new anti-obesity strategy, with a ban on unhealthy food advertising before 9pm and a campaign to encourage healthy lifestyles.

And recently, plans were unveiled for a ‘rewards program’, to start later this year, that will benefit families who eat healthier and exercise more.

Children of obese mothers are 60 percent more likely to develop mental health conditions, including schizophrenia and substance abuse problems, a study finds.


Body mass index (BMI) is a measure of body fat based on your weight in relation to your height.

Standard formula:

BMI = (weight in pounds / (height in inches x height in inches)) x 703

Metric formula:

BMI = (weight in kilograms / (height in meters x height in meters))


Under 18.5: underweight

18.5–24.9: Healthy

25–29.9: overweight

30–34.9: obese

35 or higher: Severe obesity

The study was conducted by psychologist Marius Lahti-Pulkkinen of the University of Helsinki, Finland, and his colleagues.

“Our findings of time-specific associations between maternal prenatal BMI and mental disorders in adult offspring may have important public health implications,” the researchers wrote in their paper.

The results, they added, “are particularly concerning given the increasing prevalence of severe obesity among pregnant women.”

In their study, the researchers analyzed health data related to 68,571 firstborns who took place at Aberdeen Maternity Hospital between 1950 and 1999.

Based on their body mass index (BMI) at around 15.7 weeks of pregnancy, each mother was given a weight rating on a five-point scale, from underweight to severely obese.

Finally, the team consulted the Scottish Morbidity Records and the National Records of Scotland to determine which of the children had received a mental health diagnosis between January 1, 1996 and June 8, 2017.

(The researchers had excluded from their study any child who died before this time and therefore would not have any mental health problems.)

The findings revealed that a mother’s weight during pregnancy can have long-lasting effects on their children’s mental health — with the team identifying two main trends.

In children born between 1950 and 1974, having an underweight mother (BMI less than 18.5) was associated with a 74 percent increase in the risk of developing a mental illness such as schizophrenia during adulthood.

But in the offspring born between 1975 and 1999, it was instead severe maternal obesity that led to an increased risk of mental health problems in adulthood.

Adult children born to mothers with a BMI of 35 or higher in the period 1975-1999 had a 60 percent higher risk of some form of mental disorder and, in particular, a 91 and 180 percent chance, respectively, of developing an addiction problem ( photo) or schizophrenia

Adult children born to mothers with a BMI of 35 or higher in the period 1975-1999 had a 60 percent higher risk of some form of mental disorder and, in particular, a 91 and 180 percent chance, respectively, of developing an addiction problem ( photo) or schizophrenia

What is No. 10 doing to help Britons get slimmer?

Here are some of the anti-obesity policies that have been confirmed or considered by the government in the past year:

  • Ban on junk food advertising before 9 p.m.;
  • restrictions on online advertising of unhealthy food;
  • Mandatory calorie labeling on restaurant menus;
  • Appointments with general practitioners for weight management;
  • Funding for the NHS app to help people keep track of exercise and meals;
  • Extra training for children’s medicines to prevent overweight in young people;
  • Prescribing weight loss diets, including a plan to beat diabetes, restricting people to 3x 400 kcal meals;
  • Shops will be prevented from doing BOGOF junk food deals and from placing treats at the tills.

In fact, adult children born to mothers with a BMI of 35 or higher had a 60 percent higher risk of some form of mental disorder and, in particular, a 91 and 180 percent chance, respectively, of developing an addiction problem or schizophrenia.

Of the mothers who gave birth between 1950-1974, only 4 percent were obese and 0.9 percent were severely obese. In the 1975-1999 group, however, these figures had risen to 7.1 and 2.6 percent, respectively.

As maternal obesity is more common, maternal underweight appears to have increased inversely, from 3.2 to 2.1 percent between the two groups.

However, the researchers noted that while relative risks had increased significantly, the absolute risk of children developing mental illness as adults was low, at only 1.4 percent for the children born in 1975-1999.

“The age-specific findings in our study were particularly evident in those age groups where the exposure in question was more common,” the researchers wrote.

‘Maternal underweight was more common in the older and severe maternal obesity in the younger cohort. The incidence of underweight decreased over time and severe obesity increased.’

However, the nature of the study’s dataset, the team explained, means the subjects born in earlier years would have been older when their mental health status was recorded in the Scottish Morbidity Records and National Records of Scotland databases.

Given this, it is unclear whether the time-specific findings stem from changing consequences of maternal BMI during pregnancy or whether there are different effects on different age groups of adult offspring.

In addition, the correlative nature of the study means the researchers were unable to determine exactly what it is about a mother’s underweight or obesity that increases the risk of later mental illness in their children.

However, the team speculated that this may be related to physiological stress.

“Obesity during pregnancy is a highly pro-inflammatory condition and prenatal inflammation has been associated with psychopathological risk in offspring,” they wrote.

The study’s full findings were published in the journal Scientific Reports.


Obesity is defined as an adult with a BMI of 30 or higher.

A healthy person’s BMI – calculated by dividing weight in kilograms by height in meters, and the answer again by height – is between 18.5 and 24.9.

In children, obesity is defined as being in the 95th percentile.

Percentiles compare young people with others of the same age.

For example, if a three-month-old child is in the 40th percentile for weight, that means 40 percent of the three-month-old weighs the same or less than that baby.

About 58 percent of women and 68 percent of men in the UK are overweight or obese.

The condition costs the NHS around £6.1 billion each year, out of its estimated budget of £124.7 billion.

This is because obesity increases the risk of a number of life-threatening conditions.

Such conditions include type 2 diabetes, which can cause kidney disease, blindness, and even limb amputations.

Research suggests that at least one in six hospital beds in the UK is occupied by a diabetic.

Obesity also increases the risk of heart disease, which kills 315,000 people in the UK each year – making it the leading cause of death.

Carrying dangerous amounts of weight has also been linked to 12 different cancers.

This includes breast, which affects one in eight women at some point in their lives.

In children, research suggests that 70 percent of obese youth have high blood pressure or elevated cholesterol, which puts them at risk for heart disease.

Obese children are also significantly more likely to become obese adults.

And if children are overweight, their obesity in adulthood is often more severe.

As many as one in five children in the UK attend school who are overweight or obese, rising to one in three by the time they turn 10.