Eating fried food regularly before conceiving significantly increases a woman’s risk for gestational diabetes, according to study results published in Diabetologia.
Fried food is both popular and prevalent, particularly in Western countries, although little is known about how regular consumption affects humans. Recent data have linked frequent consumption with overweight and obesity in two Mediterranean cohorts, but few epidemiological studies have assessed the connection between eating fried food regularly and other health outcomes.
To learn more, researchers evaluated 21,079 singleton pregnancies from 15,027 women in the ongoing Nurses’ Health Study II (NHS II). In the NHS II, every 2 years, participants received a questionnaire regarding disease outcomes and lifestyle behaviors. Every 4 years after 1991, the NHS II investigators polled participants on their diets, including consumption of fried foods at home and away from home using a validated food frequency questionnaire.
A total of 847 women were diagnosed with gestational diabetes during 10 years of follow-up.
Analyses yielded risk ratios for developing gestational diabetes of 1.13, 1.31 and 2.18 for women who consumed total fried foods one to three times per week, four to six times per week and seven or more times per week vs. less than once per week, respectively. After adjustments for BMI, risk ratios were 1.06, 1.14 and 1.88, respectively.
The researchers also found a statistically significant association between gestational diabetes and fried food consumption away from home but not fried food consumption at home.
“Deterioration of oils during frying is more profound when the oils are reused, a practice more common away from home than at home. This may partly explain why we observed a stronger association of GDM risk with fried foods consumed away from home than fried foods consumed at home,” the researchers wrote.
Although the exact mechanism through which frequent fried food consumption increases the risk for gestational diabetes remains unclear, the researchers speculated that the frying process may be to blame.
“Frying deteriorates oils through the processes of oxidation and hydrogenation, leading to an increase in the absorption of oil degradation products by the foods being fried, and also a loss of unsaturated fatty acids such as linoleic and linolenic acids and an increase in the corresponding trans fatty acids such as trans-linoleic acids and trans-linolenic acids.”
Higher levels of dietary glycation end products, which have been linked to insulin resistance, pancreatic beta-cell damage and diabetes, are also seen with frying, they added.
“Our study indicates potential benefits of limiting fried food consumption in the prevention of [gestational diabetes] in women of reproductive age. Further studies are warranted to confirm our findings and to discover the underlying mechanisms,” the researchers concluded.