Dairy reduces inflammation and oxidative stress in metabolic syndrome

More evidence that dairy foods contain agents with antiinflammatory and antioxidant properties is presented in a study published recently in The American Journal of Clinical Nutrition showing reductions in damaging inflammatory biomarkers. The authors state:

"Oxidative and inflammatory stress are elevated in obesity and are further augmented in metabolic syndrome. We showed previously that dairy components suppress the adipocyte- and macrophage-mediated generation of reactive oxygen species and inflammatory cytokines and systemic oxidative and inflammatory biomarkers in obesity...The objective of this study was to determine the early (7 d) and sustained (4 and 12 wk) effects of adequate-dairy (AD) compared with low-dairy (LD) diets in subjects with metabolic syndrome."

Their forty overweight or obese subjects with metabolic syndrome were randomly assigned to receive either an 'adequate dairy diet' (defined as 3.5 daily servings) or 'low dairy diet' (less than half a daily serving) form of weight-maintenance diet for 12 weeks. They measured oxidative and inflammatory biomarkers at the start and after 1, 4, and 12 weeks as primary outcomes, along with body weight and composition to start and after 4, and 12 weeks as secondary outcomes. Their data showed a dramatic difference for the 'adequate dairy' diet:

"AD decreased malondialdehyde and oxidized LDL at 7 d (35% and 11%, respectively), with further decreases by 12 wk. Inflammatory markers were suppressed with intake of AD, with decreases in tumor necrosis factor-α at 7 d and further reductions through 12 wk (35%); decreases in interleukin-6 (21%) and monocyte chemoattractant protein 1 (14% decrease at 4 wk, 24% decrease at 12 wk); and a corresponding 55% increase in adiponectin at 12 wk. LD exerted no effect on oxidative or inflammatory markers. Diet had no effect on body weight; however, AD significantly reduced waist circumference and trunk fat, and LD exerted no effect."

While these findings don't obviate the need to attend to the possibility of dairy allergies or the quality of dairy foods consumed, this is strong evidence that there agents in an 'adequate dairy' diet that can do more than a low dairy diet even when the same amount of weight is lost.

"Data from this study show that an increase in dairy intake from suboptimal to adequate levels (≈3.5 servings/d) significantly attenuates both oxidative and inflammatory stress in metabolic syndrome. Notably, although these effects may result, in part, from reductions in adiposity on higher dairy diets, the rapid onset (within the first 7 d of dietary change) suggest that there is an adiposity-independent effect as well. This is further supported by our previous evidence that showed direct effects of dairy components on adipocyte cytokine expression and secretion."