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

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Milk and dairy products in human nutrition
consumption of butter, meat, pastries, milk and sugar. In contrast, significant negative
correlation coefficients were seen for legumes, alcohol and oils. Food patterns
associated with high CHD mortality rates were characterized by high consumption
of butter, dairy products and other animal products (excluding fish), usually rich
in SFAs and cholesterol. The authors noted that their results justify interest in the
Mediterranean diet for prevention of CHD, as it is rich in plant foods and relatively
poor in animal foods.
Another large-scale study that supports cutting down high-fat dairy products
is the North Karelia Project in Finland. This comprehensive community-based
programme was started in 1972. The population of the neighbouring province
Koupio was used as a control. At the start of the project, smoking among men was
extremely common, and blood pressure levels and serum cholesterol levels were
extremely high in North Karelia, ascribed to a diet high in saturated fat, especially
dairy fat (Puska, 2010). Although the evaluation of the first five years of the project
did not show any differences in the trends in coronary mortality between North
Karelia and Kuopio (Salonen et al., 1983), annual CVD mortality rates among the
working age population in Finland as a whole have been reduced by 80 percent
since 1969 (Puska, 2009). Total fat consumption has reduced from close to 40 percent
of dietary energy to a little over 30 percent, with major reductions in saturated
fat intake and some increase in polyunsaturated fat intake. The national butter consumption
per capita has reduced from about 18 kg in 1965 to less than 3 kg in 2005
(Puska, 2009). Use of vegetable oil for cooking has increased from close to 0 percent
in 1970 to about 50 percent. Fruit and vegetable consumption has increased and
salt intake has reduced. The dietary changes have caused a remarkable reduction
in blood cholesterol levels, with a subsequent reduction in blood pressure levels in
men aged 30–59 years. However, there has been much criticism of both the original
hypothesis and subsequent representation of results of the North Karelia Project
(see Maijala, 2000 and references therein). The criticisms have included the claim
that the decrease in CHD mortality rates seen in the population of the neighbouring
province used as a control was similar to or even sometimes larger than those seen
in North Karelia.
The DASH study was a multicentre, randomized controlled clinical trial involving
459 participants that tested the effects of dietary patterns on blood pressure
(Appel et al., 1997). For three weeks prior to the intervention phase, all subjects
were fed a control diet that was low in fruits, vegetables and dairy products, with a
fat content typical of the average diet in the United States.The intervention consisted
of eight weeks on a “combination diet” that was rich in fruit and vegetables and
low-fat dairy products. This was compared with subjects assigned to a control diet
(“typical American diet”) and with subjects assigned to a fruit-and-vegetable diet
that provided high levels of potassium, magnesium, fibre, fruit and vegetables, and
fewer snacks and sweets than the control diet. The combination diet reduced blood
pressure more than the other two diets both in subjects with hypertension and in
those without hypertension. The reductions in blood pressure were achieved after
two weeks and sustained for six more weeks. The study concluded that a diet rich
in fruits, vegetables and low-fat dairy foods and with reduced saturated and total
fat contents can substantially lower blood pressure. The authors emphasized that
DASH was an 11-week feeding study. As such, it was not designed to assess either