You probably know someone with diabetes—an increasingly common disease. In 2017, more than 425 million adults were living with diabetes, and more than 1,106,500 children were living with Type 1 diabetes, globally.
There are three common types of diabetes. In Type 1, the body’s immune system attacks the cells that make insulin, the hormone that gets blood sugar (our body’s fuel) where it needs to go. In Type 2, the body makes insulin but the insulin cannot do its job. In both cases, blood sugar levels go up.
The third kind of diabetes, gestational diabetes, is temporary during pregnancy. However, our recent studies show that diabetes in one family member is related to diabetes in other family members.
Gestational diabetes in mothers is linked to future diabetes in the mothers themselves and also in their partners and children.
Couples Share Diabetes Risk
In most cases, Type 2 and gestational diabetes are related to genetics, lower physical activity, and less healthy ways of eating. Improving diet and physical activity can cut Type 2 diabetes risk by half. Studies have shown that many women with gestational diabetes go on to develop Type 2 diabetes in the decade after pregnancy.
We looked at data from about 70,000 couples who were parents in Quebec, Canada. We found that if the mother had gestational diabetes, the father was 20 percent more likely to develop Type 2 diabetes in the 10 years after pregnancy.
If the mother had both gestational diabetes and gestational hypertension—temporary high blood pressure during pregnancy—the father was 80 percent more likely to develop Type 2 diabetes in the future.
Couples share physical activity, eating, and weight patterns. We think that is why they share diabetes risk.
That’s why they should also share in efforts to improve health behaviors together and prevent diabetes development in the future.
What About the Kids?
We had information on the children of the couples we studied, from birth to 22 years old. More than 90 percent of diabetes that starts before the age of 22 in most Canadian provinces is Type 1, not Type 2.
The exception is Manitoba where there are many Indigenous Canadians, a group with an established link with diabetes and a high occurrence of Type 2 in young people.
Studies from Manitoba show a link between gestational diabetes in mothers and Type 2 diabetes in children. One study in Sweden showed a link between having either Type 2 or gestational diabetes in the mother and the development of Type 1 in the children.
We found that between birth and 22 years, the children of mothers with gestational diabetes were twice as likely to develop Type 1 diabetes. If you had 5,000 young people whom you watched for two years, our results indicate that two of them would develop Type 1 if their mom did not have gestational diabetes. Four or five would develop Type 1 if their mom did have gestational diabetes. So it is rare, but it is important.
A study also from Quebec shows that one-quarter of young people who develop Type 1 come to the hospital in a medical crisis the first time they are diagnosed. The early signs of Type 1 may be missed: being really thirsty, having to urinate more often, blurry vision, some unexplained fatigue.
Understanding the link to gestational diabetes might be another useful piece of the puzzle—to push young people, their families, and their health care providers to consider the possibility of diabetes, just as they do when their parents are known to have Type 1 or Type 2.
Gestational Diabetes is a Family Affair
We don’t yet know why there is a link between gestational diabetes in mothers and Type 1 in young people. The important thing to remember though is that gestational diabetes is a family affair.
Future Type 2 diabetes can be prevented in many family members within the home environment—by eating more home-cooked, healthy meals and fruits and vegetables, by reducing fried foods and eating out, and with a whole-family emphasis on being active.
Type 1 diabetes, though rare, might also be diagnosed earlier in children and teens, with an awareness of the link to moms’ gestational diabetes.
is an associate professor of medicine at McGill University in Canada; physician-scientist and director of the Centre for Outcomes Research and Evaluation at the McGill University Health Centre at McGill University. This article was first published on The Conversation.