Potatoes Before Pregnancy Linked to Gestational Diabetes, Study Suggests

Potatoes are the world’s fourth largest food crop, with Americans eating an average of 125 pounds of spuds per person each year. But according to new research from the National Institutes of Health (NIH), higher potato consumption before pregnancy is associated with increased rates of gestational diabetes.

Gestational diabetes develops during pregnancy, generally during the second or third trimester, as a result of certain hormones released during that time that work against the action of insulin. It affects roughly seven out of every 100 pregnant women in the United States and increases the baby’s risk of conditions such as obesity and Type 2 diabetes and the mother’s risk of Type 2 diabetes.


Although potatoes are high in a variety of nutrients, previous research has indicated that they can cause spikes in blood sugar due to their large amounts of quickly absorbed starch. Roughly 35% of women of reproductive age in the U.S. eat potatoes on a daily basis. To evaluate the association between eating potatoes before becoming pregnant and the risk of developing gestational diabetes, researchers looked at data from 1991–2001 of over 15,000 women from the Nurses’ Health Study II. The participants, who were more than 90% white and had no history of chronic disease or gestational diabetes, were asked to fill out questionnaires every four years reporting on the types of foods they had eaten in the previous year. For potatoes specifically, the women were asked whether they had eaten them baked, boiled, mashed, as fries, or as chips, with frequencies ranging from “never” to “six or more times a day.”

The researchers found that women who reported eating more potatoes before becoming pregnant had a higher risk of gestational diabetes, which developed in 854 of the 21,693 pregnancies over the study period. The association remained even after controlling for other factors that can increase the risk of the condition, such as age, family history, general diet quality, and body-mass index. Those who ate a serving (roughly a cup) or more of the tubers a week were at higher risk than those who ate few or no potatoes, with increased consumption being associated with increased risk.

Study limitations include the possibility of errors in the self-reported amount of potato consumption and self-reported cases of gestational diabetes.

Although the research was observational, and not intended to show cause and effect, the findings raise concerns about U.S. guidelines that encourage consumption of potatoes, the study authors say. “Higher levels of potato consumption before pregnancy are associated with greater risk of gestational diabetes mellitus, and substitution of potatoes with other vegetables, legumes, or whole-grain foods might lower the risk,” they note.

However, according to Doctor of Education and registered dietitian Keith-Thomas Ayoob, EdD, RD, FAND, in an interview with Medscape, the study has many limitations, including that it did not take into account the effect of weight gained during pregnancy. “Anybody who’s got gestational diabetes didn’t get it because of potatoes. If you have gestational diabetes, you better watch your total diet, period,” he states.

For more information, see the article “Pre-pregnancy potato consumption may be linked to gestational diabetes risk” or the study’s abstract in the journal The BMJ. And to learn more about risks of and treatment approaches for gestational diabetes, read our three-part series on gestational diabetes by certified diabetes educator and registered dietitian Amy Campbell.

If you are a high school senior with Type 1 diabetes, you may be interested in applying for one of the college scholarships being offered by the Diabetes Scholars Foundation. Bookmark DiabetesSelfManagement.com and tune in tomorrow to learn more.