Milk-and-Dairy-Products-in-Human-Nutrition-FAO

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Milk and dairy products in human nutrition
Dietary patterns with higher dairy intake have been shown to be associated with
reduced risk of some of the MetS components (Appel et al., 1997; Azadbakht et al.,
2005; Tremblay and Gilbert, 2009). In a systematic review of observational evidence,
Tremblay and Gilbert (2009) reported that the odds for developing MetS was 0.71
(95 percent CI: 0.57–0.89) for the highest dairy intake (3–4 servings per day) versus
the lowest dairy intake (0.9–1.7 servings per day). Dairy consumption was also
found to have favourable effects on blood pressure and obesigenic parameters, albeit
the results were less consistent. Appel et al. (1997) showed that a combination of
fruits, vegetables and low-fat dairy (the so-called “Dietary Approaches to Stop
Hypertension (DASH) diet”) resulted in the greatest reductions in blood pressure,
whereas a fruit and vegetable diet that excluded dairy products was about half as
effective. A DASH diet was also found to increase HDL cholesterol, lower triglycerides,
lower blood pressure, promote weight loss and reduce fasting blood glucose
in both men and women in Tehran as compared with the control diet (Azadbakht
et al., 2005). In a French prospective study with a nine-year follow-up, Fumeron
et al. (2011) reported that “dairy (except cheese) consumption and dietary calcium
density were inversely associated with incident MetS and T2DM and all parameters
were associated with lower diastolic blood pressure and triglycerides”.
Although some studies suggest that consumption of dairy food may have a beneficial
impact on the MetS components (Mensink, 2006; Pfeuffer and Schrezenmeir,
2007; Fumeron et al., 2011), Dietary Guidelines Advisory Committee (DGAC)
(2010) concluded that there is limited evidence demonstrating that consumption of
milk and dairy products is associated with reduced risk of MetS. 28 There is, however,
moderate evidence showing an association between milk and dairy product
consumption and lower incidence of T2DM in adults 29 (DGAC, 2010). A number
of review studies have been published since the DGAC (2010) report. In a systematic
review and meta-analysis involving five cohorts involving 184 454 participants,
the relative risk for T2DM was estimated to be 15 percent lower in people who had
a high milk intake 30 (Elwood et al., 2010). In another meta-analysis of seven cohort
studies involving 328 029 participants, Tong et al. (2011) also found an inverse association
between dairy consumption and T2DM, especially low-fat dairy (RR 0.82,
95 percent CI: 0.74–0.90) and yoghurt (RR 0.83, 95 percent CI: 0.74–0.93). Consumption
of high-fat dairy foods and whole milk was not associated with the risk
of T2DM. In a recent systematic review of dairy consumption and MetS involving
10 cross sectional studies (36 113 participants) and three prospective cohort studies
(13 795 participants), Crichton et al. (2011) reported that the majority of studies
28 The conclusion reached for the relationship between milk/milk products and MetS was based on one
systematic review with meta-analysis (Elwood et al., 2008), one prospective cohort study (Snijder et
al., 2008) and two cross-sectional studies (Ruidavets et al., 2007; Beydoun et al., 2008).
29 The conclusion reached for the relationship between milk/milk products and T2DM was based
on the systematic review with the meta-analysis of four prospective studies on diabetes (Elwood
et al., 2008).
30 Within the studies, the quantity of milk defined as high and low varied. Most of the studies used
quartiles or quintiles of the distribution of intakes while other studies reported the occasion or
frequency, for example two or more servings of dairy foods per week versus less than one serving
per month.