How much we eat as an infant may predict how we age, a new study suggests.
Researchers at Baylor College of Medicine found that mice that are overfed as babies showed genetic changes linked to aging prematurely compared to mice that ate adequate amounts as pups.
These same kinds of changes happen to humans who develop type 2 diabetes and some studies suggest they may predict the onset of the disease.
As the obesity epidemic rages on, the study authors believe their work demonstrates how over-eating – even in the earliest days of our lives – may drive weight-gain and, in turn, declining health earlier in life.
Making sure a newborn is well-fed is priority number one for new parents.
It’s extremely rare for a baby to be technically ‘overfed,’ but it’s possible.
And while there may not be much risk of doing immediate harm to infants by feeding them too much, the new study, published in Environmental Epigenetics, suggests it might have an impact down the line.
To find out if this might be the case, the Baylor scientists raised two groups of mice. The control group was fed normal, measured meals for the first 21 days of their lives – the rough mouse equivalent of ‘infancy.’
The other group was given the run of an ‘all you can eat buffet.’
With no researchers taking away their smorgasbord, the mouse pups ate far too mcuh.
And as the researchers suspected, the mice not only became overweight but showed genetic changes the team believes are related to over-nutrition.
Studies of humans with type 2 diabetes, for which obesity is a major risk factor, have identified epigenetic changes not seen in people that don’t have the disease.
Cells called islets in the pancreas don’t function properly in people with either type 1 or type 2 diabetes.
Both involve inherited risks but type 1 – also called juvenile diabetes – typically develops in childhood or adolescence.
Type 2 diabetes develops in later adulthood in most people and may be preventable if someone keeps up a healthy lifestyle and eating habits.
In people with type 2, the DNA in their islet cells tend to pick up rogue chemical tags, called methyls.
These bits of chemicals may disrupt the function of the islet cells, potentially triggering type 2 diabetes.
Other research has suggested the this tagging process, called methylation, may be a predictor of age-related health issues.
Methyls don’t typically start appearing until later in life – but in the mouse pups that were given access to the endless buffet, the chemical tags showed up right away.
‘By the age of weaning, islets of overnourished mice show an epigenetic profile resembling that of much older mice,’ said study co-author Dr Robert Waterland.
‘Our interpretation is that postnatal overnutrition causes accelerated epigenetic aging in the islets.’
Previous studies have shown that overfed mouse pups tend have more health problem of all sorts s they age – but issues related to blood sugar levels are particularly common.
‘Since the ability to regulate blood sugar declines with age, this premature epigenetic aging may help explain how overnutrition during infancy increases the risk of diabetes later in life,’ Dr Waterland explained.
And the same phenomenon may be at play in people who were fed excessively as infants and set up for lifetime risks of obesity and diabetes.
‘In these days of escalating pediatric overnutrition and obesity, we urgently need to understand the adverse consequences of overnutrition in human infancy,’ said Dr Waterland.
‘I believe that optimizing nutrition during these critical periods of development will prove to be an effective approach to prevent adult disease.’