Dairy Products May Lower Risk of Type 2 Diabetes in Men

[Guest guest]

May 10, 2005 - Men who have a high dairy intake have a lower risk of type 2

diabetes mellitus (DM), according to the results of a prospective study

published in the May 9 issue of the Archives of Internal Medicine. The

editorialist reviews the purported benefits of milk and dairy products.

" Diet and lifestyle modifications can substantially reduce the risk of type

2 diabetes, " write Hyon K. Choi, MD, from Massachusetts General Hospital in

Boston, and colleagues. " While a strong inverse association has been

reported between dairy consumption and the insulin resistance syndrome among

young obese adults, the relation between dairy intake and type 2 diabetes is

unknown. "

The investigators prospectively examined the relationship between dairy

intake and incident cases of type 2 DM in 41,254 male participants with no

history of DM, cardiovascular disease, and cancer when enrolled in the

Health Professionals Follow-up Study.

During 12 years of follow-up, there were 1,243 incident cases of type 2 DM.

Dairy intake was associated with a modestly lower risk of type 2 DM.

Compared with men in the lowest quintile of dairy intake, the relative risk

(RR) for type 2 DM in men in the top quintile of dairy intake was 0.77 (95%

confidence interval [CI], 0.62 - 0.95; P for trend = .003), after adjustment

for body mass index (BMI), physical activity, dietary factors, and other

potential confounders.

For each serving-per-day increase in total dairy intake, there was a 9%

lower risk for type 2 DM (multivariate RR, 0.91; 95% CI, 0.85 - 0.97). The

corresponding RR was 0.88 (95% CI, 0.81 - 0.94) for low-fat dairy intake and

0.99 (95% CI, 0.91 - 1.07) for high-fat dairy intake. BMI did not affect

this association (< 25 vs >/= 25 kg/m2; P for interaction, .57).

" Dietary patterns characterized by higher dairy intake, especially low-fat

dairy intake, may lower the risk of type 2 diabetes in men, " the authors

write.

Study limitations include observational design, potential for unmeasured

confounding, self-reporting of DM with possible underdiagnosis, and study

population limited to men 40 years old and older with no history of type 2

DM.

The National Institutes of Health supported this study in part. The authors

report no financial disclosures.

In an accompanying editorial, Janet C. King, PhD, from Children's Hospital

Oakland Research Institute in California, calls this study " a further

reminder of the potential importance of dairy intake and the continuing

value of research in this area. " She notes that milk contains amino acids,

vitamins, minerals, and additional bioactive components.

" Many of these components protect individuals from exogenous stresses,

toxins, and pathogens; encourage adaptation to the environment; and promote

metabolic regulation, while other milk components cause negative effects in

susceptible individuals, " Dr. King writes. " Research shows that the role of

dairy foods in health is very complex and probably varies with the genotype

and phenotype of the individual. "

Dr. King reports no financial conflicts of interest.

Arch Intern Med. 2005;165:975-976, 997-1003