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

Chapter 4 – Milk and dairy products as part of the diet 119
suggest that the protein in milk maybe a marker for other factors in the nonlipid
component of milk.
Another study looked at milk consumption and height in American children by
analysing NHANES data from 1999–2002 (Wiley, 2005). For adults, data on early
consumption were obtained from questions about milk consumption in childhood.
Results indicated that adult height was positively associated with milk consumption
at ages 5 through 12 years and 13 through 17 years. For children (5–18 years), two
types of data were used: participants rated the frequency of their milk intake in the
last 30 days and information was gathered from a 24-h dietary recall, which provided
a snapshot of current milk intake. Among these children, frequency of milk
consumption over the past 30 days had no effect on the height of 5–11-year-olds,
but 30-day frequency of milk consumption and milk intake (measured as grams of
milk, or protein or calcium from milk) were significant predictors of the height of
12–18-year-olds, along with age, gender, household income and ethnicity. However,
the authors note that the effect of milk on height was modest (Wiley, 2005).
A study of 250 children in New Zealand aged 3–10 years found that long-term
avoidance of cow milk was associated with small stature and poor bone health
(Black et al., 2002). Similar results were reported by Rockell et al. (2005), who
followed changes over two years of a group of 46 Caucasian children in the United
States with an initial mean age of 8.1 years. The children had low calcium intakes
at baseline and were short in stature. At follow-up, modest increases in milk consumption
and calcium intake had occurred. Although some catch-up in height had
taken place, the group remained significantly shorter than the reference population
of milk-drinking children from the same community (Z scores −0.39±1.14). A
longitudinal study conducted in Japan involving 92 children, average age 9.5 years,
reported that the mean height gain in those consuming more than 500 ml of milk/
day was greater than that of those consuming less than 500 ml/day; the difference
in height gain between the two groups was 2.5 cm over three years (Okada, 2004).
In conclusion, much of the evidence suggests that milk promotes linear growth in
well-nourished children, although gains may be modest and not always statistically
significant. The two available studies on well-nourished preschool children suggest
that this effect may be more pronounced in younger children.
4.3.4 Secular trend of increasing adult height
During recent decades, adult height has increased steadily in most European countries
and in the United States (see Hoppe, Mølgaard and Michaelsen, 2006 and references
therein). These changes have been ascribed to a general improvement in living
conditions, accompanied by a change in nutritional status and food consumption
patterns, including a greater consumption of milk and other ASFs. The secular trend
in height in Japanese children has been mainly ascribed to increased milk consumption:
regional differences in height were found to correspond to milk consumption
in the national school lunch programme in Japan (Takahashi, 1984). These results
are consistent with the observation that nomadic or pastoral people living on milk
in arid areas are usually taller than people whose livelihoods are cultivation-based
(Takahashi, 1984).
A recent study conducted in India on a large nationally representative sample of
people shows that a secular trend in adult height has also begun to occur in some