A new systematic review has summarised the findings of observational research into the association between coffee and type 2 diabetes.
Is coffee intake associated with an increased risk of developing diabetes?
The reviewers wanted to explore whether different amounts of coffee intake affected the risk differently.
The reviewers searched MEDLINE for cohort studies published between 2001 and 2011. They combined the data from 13 studies, they found that:
Participants who drank 4 to 6 cups and more than 6 to 7 cups of coffee per day had a lower risk of type 2 diabetes compared with those who drank less than 2 cups per day.
Users of this research should consider:
- The literature search was not exahustive and probably missed important studies.
- It’s not clear whether the reviewers rigorously evaluated the quality of the individual studies.
- Did they adjust the data for other important confounders?
- It’s not clear whether the review included both retrospective and prospective studies.
- Were the participants assembled at equivalent stages or levels of risk of developing diabetes?
- Were the findings consistent from one study to another?
- We can’t say from this review of observational research that coffee reduces the risk of type 2 diabetes.
Muley A, Muley P, Shah M. Coffee to Reduce Risk of Type 2 Diabetes? : A Systematic Review. Curr Diabetes Rev. 2012 Apr 12. [Epub ahead of print]