A recent study published in Primary Care Diabetes has explored the potential association between coffee and cola consumption, caffeine intake, and the risk of developing gestational diabetes mellitus (GDM).
GDM, a condition often accompanying late childbearing and prevalent obesity, affects over one in five women in Finland, where the study was conducted. Infants born to mothers with GDM are at increased risk of being macrosomic, experiencing neonatal hypoglycemia, and facing complications during delivery or in utero.
Long-term complications for mothers with GDM include the heightened likelihood of developing type 2 diabetes and metabolic syndrome later in life. This risk also extends to their adult offspring, along with an increased susceptibility to obesity.
Coffee consumption is widespread in Western nations, with Finland boasting the highest levels, averaging 9 kg per person annually. The study was conducted in Finland to investigate this context.
Outside of pregnancy, coffee consumption has been associated with a reduced risk of type 2 diabetes, possibly due to coffee compounds favoring lipid and glucose metabolism. However, the specific effect of high caffeine and coffee intake on GDM risk remains uncertain.
Pregnancy guidelines typically advise limiting caffeine intake to 200 mg per day, roughly equivalent to one mug or two small cups of coffee. This caution stems from reported links between caffeine consumption during pregnancy and fetal growth restriction (FGR) or small for gestational age (SGA) babies. Nonetheless, studies have indicated that moderate caffeine and coffee intake may offer protection against GDM.
The study aimed to examine the relationship between caffeine, coffee, and cola consumption and the incidence of GDM. Data were sourced from the Kuopio Birth Cohort (KuBiCo), which tracked pregnant women attending prenatal clinics in outpatient health centers, all of whom delivered at Kuopio University Hospital in Finland.
Key Findings:
The study encompassed over 2,000 pregnant women, whose first-trimester dietary habits were documented via a food frequency questionnaire. Most participants underwent an oral glucose tolerance test between 24 and 28 weeks to diagnose GDM, with approximately one in five women receiving such a diagnosis.
Women diagnosed with GDM tended to be older, possess a higher body mass index (BMI), and exhibit lower weight gain during pregnancy compared to their non-GDM counterparts. Additionally, their infants were more likely to be delivered prematurely but with higher birth weights.
The median total caffeine intake among participants was 122 mg/day overall, with similar figures observed between women with and without GDM. Coffee intake was also comparable between the two groups, although those with GDM reported slightly higher consumption levels.
While cola and energy drink consumption showed marginal differences between women with and without GDM, those diagnosed with GDM tended to consume more of these beverages on average.
Notably, a third of pregnant women exceeded the recommended 200 mg daily caffeine limit, with half of coffee drinkers surpassing this threshold. Conversely, approximately 30% of participants abstained from coffee consumption entirely during the first trimester.
Moderate coffee consumption displayed a slight protective association against GDM, with a 13% reduction in risk compared to non-coffee drinkers. However, this effect became statistically insignificant when adjusting for multiple confounding factors, suggesting that moderate coffee consumption does not significantly influence GDM risk.
First-trimester caffeine intake did not demonstrate any association with GDM incidence.
Conversely, increased cola consumption was associated with a higher risk of GDM. Women consuming more than 33.3 mL of cola daily exhibited approximately a 30% increased risk of GDM compared to those consuming less.
While sugary cola consumption did not show a significant link to increased GDM risk, the odds of developing GDM were 34% higher among those consuming low-calorie cola drinks after adjusting for age and 24% higher after accounting for additional factors.
Implications:
High coffee consumption is prevalent in Finland, with a significant portion of pregnant women exceeding recommended caffeine limits. However, the study’s significant findings were primarily associated with low-calorie cola drinks, warranting replication in future research.
The absence of a protective effect from caffeine or coffee consumption, combined with the known risks of high caffeine intake during pregnancy, underscores the importance of further investigation in this area.
The observation that women diagnosed with GDM tended to have higher pre-pregnancy weights but lower weight gain during gestation suggests the potential efficacy of pregnancy weight management programs offering dietary advice and lifestyle counseling.
Finland’s comprehensive screening and treatment protocols for GDM make it an ideal setting for such research endeavors, benefitting from systematic and reliable data collection across nearly all pregnant women in the country.
