ORLANDO, Fla. — A review of prospective, observational studies suggests there is a 4% to 10% decrease in the risk for developing diabetes with higher dairy consumption, but more studies are needed to solidify the association, according to a speaker here.
“It has been shown that dairy food is associated with an overall healthier eating pattern, [along with a] healthier lifestyle and higher socioeconomic status,” Joanna Mitri, MD, MS, a research associate in the section on clinical, behavioral and outcomes research for the lipid clinic at Joslin Diabetes Center and clinical instructor at Harvard Medical School, said during a presentation. “However, with the self-reporting of dietary information [from food frequency questionnaires], there are always errors. It relies on subjective reporting, [which leads to an] inaccurate capturing of data.”
To examine the role of dairy foods in diabetes risk prevention, Mitri reviewed several observational studies, meta-analyses and clinical trials.
Mitri discussed a sample of prospective, observational studies. One suggested that the risk for developing diabetes was about 32% lower in participants who consumed high quantities of dairy vs. low dairy, whereas another showed no association between diabetes and dairy intake.
Meta-analyses looking at the effect of dairy on diabetes prevention may be more reliable, but still examine data from prospective, observational studies and depend on the quality of those studies, again creating difficulty in determining whether the data correlate to actual dairy consumption patterns, according to Mitri. Nevertheless, there seems to be a good correlation between food frequency questionnaire and dairy intake.
Data from meta-analyses of observational studies consistently show that dairy and, specifically, yogurt are closely associated with decreased risk for diabetes. Milk and cheese have less consistently been associated with diabetes. Results for high-fat dairy predominately show a neutral association with diabetes; these foods neither increase nor decrease diabetes risk, she said.
A variety of short-term trials in small cohorts suggest that consuming dairy has little or no effect on HbA1c and may increase weight. However, dairy intake might help in weight loss if part of an energy restricted plan. This could be due to the fact that dairy is such a dense food, made of fatty acids, amino acids, vitamins, minerals and probiotics. Mitri noted the difficulty in conducting useful trials relating dairy to glycemic outcomes since it cannot be compared to a placebo. Furthermore, it is sometimes difficult to attribute the effect of adding dairy in the intervention arm when the control arm has also made an intervention of decreasing dairy, for example, or adding another food item that might itself have an effect on glucose.
Most of the evidence we have points toward reduced risk of diabetes with dairy intake. However, we are in need of higher evidence studies. Whether dairy reduces the risk for diabetes, Mitri said, people shifting between diet patterns should aim for isocaloric substitutions to maintain weight.
“Just adding dairy without replacing it might not work, even if you believe the food is good,” Mitri said.
She finished her presentation by recommending to include dairy in the overall eating pattern and to substitute it to another food item rather than simply adding to the rest of the habitual eating pattern. – by Melissa J. Webb
Mitri J. The role of dairy food in diabetes risk reduction. Presented at: American Diabetes Association 78th Scientific Sessions; June 22-26, 2018; Orlando, Fla.
Disclosures: Mitri reports receiving research support from the National Dairy Council and KOWA. She has received consultant fees from Cut Health.