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

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Milk and dairy products in human nutrition
increased risk of malignancy (Huxley et al., 2009), with cigarette smoking believed
to cause almost 50 percent of cases in high-income countries (WCRF and AICR,
2007). As most metabolites are excreted through the urinary bladder, food such as
milk could influence the risk of bladder cancer (Larsson et al., 2008).
4.9.5 Childhood consumption of milk and dairy products and risk of cancer
in adulthood
Recent research has focused on the “programming effects” of milk via the IGF-1
axis, as discussed in Section 4.3.5 (van der Pols et al., 2007; Martin, Holly and
Gunnell, 2011). High concentrations of IGF-1 are associated with an increased
risk of prostate, breast and colorectal cancer (Hoppe, Mølgaard and Michaelsen,
2006). The Boyd Orr study found that a family diet rich in dairy products during
childhood resulted in a greater risk (with a near-tripling of the odds) of colorectal
cancer in adulthood (van der Pols et al., 2007). Milk intake was also associated with
colorectal cancer risk. However, high milk intake was weakly inversely associated
with prostate cancer risk. Childhood dairy intake was not associated with breast and
stomach cancer risk, while a positive association with lung cancer was confounded
by smoking during adulthood (van der Pols et al., 2007). Some of these finding are
in contrast to findings of adult intake by WCRF and AICR (2007) (see below).
4.9.6 Recommendations by the World Cancer Research Fund/American
Institute for Cancer Research
WCRF and AICR (2007) examined the relationship between diet and the risk of
cancer. The key aims of the report were to summarize, assess and judge the most
comprehensive body of evidence yet collected and displayed on the subject of
food, nutrition, physical activity, body composition and the risk of cancer. To keep
the evidence current and updated into the future, an ongoing review of scientific
literature is carried out under the Continuous Update Project (CUP). The CUP
provides an impartial analysis and interpretation of the data as a basis for reviewing
and, where necessary, revising WCRF/AICR’s Recommendations based on the
Second Expert Report. Table 4.5 shows the relationship between milk and dairy
product consumption and cancer, as identified by the report (WCRF and AICR,
2007, 2008a, 2008b).
WCRF and AICR (2007) concluded that milk probably protects against colorectal
cancer and that there is limited evidence suggesting that milk also protects
against bladder cancer. There is limited evidence that cheese is a cause of colorectal
cancer. Diets high in calcium are a probable cause of prostate cancer and there is
limited evidence suggesting that high consumption of milk and dairy products is a
cause of prostate cancer. These conclusions were supported by WCRF and AICR
(2008a, 2008b). However, WCRF and AICR (2008a, 2008b) were not able to reach
a conclusion regarding the relationship between milk and dairy products and breast
cancer due to insufficient data. Although the reports emphasized that the overall
recommendation is not for diets containing no meat or foods of animal origin, they
note that most diets that are protective against cancer are mainly made up from
foods of plant origin.
Several review studies on the role of milk and dairy and risk of cancer have been
published recently (Lampe, 2011; Li et al., 2011; Mao et al., 2011; Aune et al., 2012).