There have been previous studies that found a possible relationship between the consumption of dairy and a lower risk of diabetes, high blood pressure, and metabolic syndrome. However, these studies primarily focused on North America and Europe and excluded other regions of the world. This new study looked to a broader range of countries using data collected from the Prospective Urban Rural Epidemiology (PURE) study.
For this study, participants were aged 35 to 70 and came from 21 countries including Argentina; Bangladesh; Brazil; Canada; Chile; China; Colombia; India; Iran; Malaysia; Palestine; Pakistan; Philippines, Poland; South Africa; Saudi Arabia; Sweden; Tanzania; Turkey; United Arab Emirates, and Zimbabwe.
Food Questionnaires
Researchers analyzed dietary intake over 12 months using Food Frequency Questionnaires. Dairy intake included milk, yogurt, yogurt drinks, cheese, and dishes prepared with dairy products and were classified as full or low fat (1-2%). Butter and cream were assessed separately because they are not commonly consumed in some of the countries studied.
Approximately 190,000 participant’s health records were tracked for an average of nine years as part of the study. During this time, 13,640 people developed high blood pressure and 5,351 developed diabetes.
Of these participants, an 11–12% lower risk of both high blood pressure and diabetes was recorded in those who consumed at least two servings of dairy a day. This number rose to 13-14% lower risk for three daily dairy servings. All associations were stronger for full fat compared to low-fat dairy.
It was found that two servings a day of total dairy were associated with a 24% lower risk of most components of metabolic syndrome and 28% for full-fat dairy alone, compared to no daily dairy intake. Data on all five components of metabolic syndrome were assessed including high blood pressure, waist circumference, high-density cholesterol, blood fats, and blood glucose. The greatest association was found in countries with normally low dairy intakes.
The authors of the study do acknowledge that the patterns they noticed may be due to participants’ overall diet, although it had been adjusted for in the analysis.
Researchers also caution that this is purely an observational study and can’t fully establish cause. They hope future studies will entail large randomized trials of the effects of different types of dairy-rich diets on long term blood pressure and diabetes.
However, they do suggest, “If our findings are confirmed in sufficiently large and long term trials, then increasing dairy consumption may represent a feasible and low-cost approach to reducing metabolic syndrome, hypertension, diabetes, and ultimately cardiovascular disease events worldwide.”