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

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Milk and dairy products in human nutrition
result of the additional energy intake. Fat intake (total or from dairy, vegetable or
other source) was not significantly associated with weight gain after energy adjustment,
suggesting that the most important predictor of weight change is total energy
intake. Notably, dietary calcium and low-fat milk (skim and 1 percent milk) were
also associated with weight gain. The effects of dietary calcium and milk appear to
be explained by energy intake as the associations were attenuated when energy was
adjusted (Berkey et al., 2005).
4.6.3 Dairy as part of a weight loss strategy
Calcium and 1,25-hydroxyvitamin D regulate lipid metabolism in adipose cells by
stimulating fatty acid oxidation and suppressing lipogenesis. Studies also suggest
that calcium may decrease fatty acid absorption and increase faecal fat losses (Caan
et al., 2007). However, experimental data in this area are inconclusive. Few studies
have investigated the effect of calcium on weight and these have tended to be of
short duration with small sample sizes and results should be interpreted with caution
(Theobald, 2005; Caan et al., 2007).
Cross-sectional epidemiological studies indicate that high dairy food intake
can affect weight management, but prospective studies and randomized controlled
intervention trials have yielded inconsistent results. Some clinical studies have
shown that diets that include three servings of dairy foods per day may enhance
body weight and/or fat loss and reduce abdominal fat compared with those that
contain little or no dairy (Zemel et al., 2004; Zemel et al., 2005a, 2005b). However,
this effect is generally seen in obese and overweight individuals when calories are
moderately restricted and dairy/calcium intakes are increased from inadequate to
adequate (Zemel et al., 2004; Zemel et al., 2005a, 2005b).
Tremblay and Gilbert (2011) reported that low dietary calcium is a risk factor
for overweight and obesity and that calcium/dairy supplementation may accentuate
the impact of a weight-reducing programme in obese people with a low calcium
intake. However other studies refute any impact effect of calcium supplementation
on weight loss, and some suggest that intakes of milk and dairy must surpass a
threshold before beneficial effects on body weight are seen (Harvey-Berino et al.,
2005; Ferland et al., 2011; Rosado et al., 2011). In a systematic review of the effects
of calcium supplementation on body weight, Trowman et al. (2006) concluded
that supplementation with calcium supplements or dairy products has no statistically
significant association with a reduction in body weight. The Women’s Health
Initiative RCT of calcium and vitamin D supplements, which involved 36 282
postmenopausal women and lasted more than seven years, reported a minimal
effect of calcium on weight, primarily in participants who had reported inadequate
calcium intakes (Caan et al., 2007) . The authors also remarked that the benefit of
calcium on weight maintenance may be small, and may have been detected in this
RCT only because of its large sample size. Using data from the prospective cohort
Health Professionals Follow-up Study, Rajpathak et al. (2006) concluded that the
data do not support the hypothesis that an increase in dairy or calcium intake is
associated with lower long-term weight gain in men. Theobald (2005) states that
“further research is required in this area to determine whether or not calcium plays
a role in weight management and if so what the mechanisms may be. It is too early
to promote weight-loss benefits of additional calcium” (Theobald, 2005).