2nd Summit on the Health Effects of Yogurt -San Diego- Yogurt and type 2 Diabetes - Prof N. Forouhi

Nita Forouhi, PhD -University of Cambridge School of Clinical Medicine, UK

With the unrelenting escalation in the global burden of type 2 diabetes and its related consequences, strategies for its prevention are urgently needed. Despite evidence that lifestyle interventions are effective in the primary prevention of diabetes, in day-to-day practice there is uncertainty on the specific dietary factors that relate to diabetes risk or the optimal dietary advice for individuals and populations. There is accumulating evidence that dairy products intake may be inversely associated with risk of type 2 diabetes, but limitations of research have included inconsistencies of findings, and lack of clarity on associations with dairy sub-types. We set out to address these research uncertainties using two distinct but complementary approaches.
Firstly, within the EU-funded InterAct project across 8 countries of Europe, we investigated the association of the consumption of the amount and type of dairy products, assessed using food frequency questionnaires, with the development of new-onset type 2 diabetes1. In a large nested case-cohort design based on cohorts from 26 European centres of the European Prospective Investigation into Cancer (EPIC) study, we ascertained 12,403 cases of type 2 diabetes and randomly selected 16,835 sub-cohort participants from a total cohort with nearly 4 million person years of follow-up. We found no significant association with total dairy products intake, but higher combined intake of fermented dairy products (cheese, yogurt, and thick fermented milk) was inversely associated with diabetes (hazard ratio 0.88; 95% CI: 0.78, 0.99; P-trend = 0.02) in adjusted analyses comparing extreme intake quintiles. In a second approach, we took advantage of the greater detail of information from a prospective 7-day food diary in a nested case-cohort design (892 type 2 diabetes cases; 4000 sub-cohort participants) in the UK-based EPIC Norfolk study2. We found that higher consumption of low-fat fermented dairy products was associated with a lower risk of new-onset diabetes over 11 years, compared with non-consumption. Low-fat fermented dairy products largely (87%) consisted of yoghurt but also included unripened cheese, such as fromage frais and low-fat cottage cheese, in a middle-aged population in the UK. Other types of dairy, and total dairy, were not significantly associated with type 2 diabetes risk.
While we try to understand mechanisms of association and investigate cause-effect relationships, our collective epidemiological findings suggest that specific types of dairy product may help prevent diabetes within overall healthy lifestyles. They also highlight the importance of considering food group subtypes, rather than overall food-group categories, when examining the role of diet in the prevention of chronic diseases.

About The Yogurt in Nutrition Initiative (YINI)