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

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Milk and dairy products in human nutrition
Fermented milk products may be better tolerated by people with lactose intolerance,
primarily because they contain less lactose (Panesar, 2011). In particular,
yoghurt containing live bacteria may be better tolerated by lactose malabsorbers
because of the β-galactosidase in the yoghurt or the presence of bacteria in the
yoghurt that produce β-galactosidase in the small intestine. Furthermore, yoghurt
takes longer to pass through the digestive system than does milk, thus allowing
more effective breakdown of lactose (Buttriss, 1997).
Lactic acid bacteria (LAB) in fermented milks can affect food-borne pathogens.
In Zimbabwe, LAB cultures isolated from naturally fermented milk (amasi) were
shown to inhibit the survival and growth of the human pathogens Escherichia coli
and Salmonella enteriditis (Mufandaedza et al., 2006). In a study from Tibet, the
bacteriocins produced by the LAB strains from kurut, a fermented milk, showed
antimicrobial activity and were resistant to high temperatures (Luo et al., 2011).
However, the authors also remarked that “further research is necessary to purify
the bacteriocins and study their detailed characters before its application in food
fermentation” (Luo et al., 2011).
St-Onge, Farnworth and Jones (2000) reported that “existing evidence from
animal and human studies suggests a moderate cholesterol-lowering action of fermented
dairy products”, while Kiessling, Schneider and Jahreis (2002) demonstrated
that daily consumption of fermented milk products for six months increased serum
HDL-cholesterol, and improved the LDL/HDL ratio in women. Andrade and
Borges (2009) examined the effect of milk fermented with Lactobacillus acidophilus
and Bifidobacterium longum on plasma lipids of women with normal or moderately
elevated cholesterol in a double-blind, cross-over study. Women with a baseline
total cholesterol greater than 190 mg/dl who consumed the fermented milk showed
a reduction in LDL-cholesterol. Other studies have explored the relationship
between fermented milk consumption and hypertension. Usinger, Ibsen and Jensen
(2009) reviewed human intervention studies of the possible antihypertensive effect
of fermented milk and concluded that the “results are diverging, and the antihypertensive
effect is still debatable”. Usinger, Reimer and Ibsen (2012) concluded that
fermented milk has no effect on blood pressure and that the results of the review
“do not give notion to the use of fermented milk as treatment for hypertension or
as a lifestyle intervention for pre-hypertension nor would it influence population
blood pressure”. Sonestedt et al. (2011) examined the association between the
intake of milk, cheese, cream and butter and the incidence of CVD in the Swedish
Malmo diet and cancer cohort. The milk was separated into fermented (yoghurt and
cultured sour milk) and non-fermented milk. The authors reported that the highest
intake category of fermented milk was associated with 15 percent (95 percent confidence
interval: 5-24 percent; P trend=0.003) decreased incidence of CVD relative
to the lowest intake category. However, such correlations from epidemiological
studies do not demonstrate cause-effect relationships, hence caution is needed when
interpreting epidemiological results.
Interestingly, it has been reported that yoghurt consumption can benefit vulnerable
populations, including malnourished people and those with human immunodeficiency
virus (HIV) (Solis et al., 2002). Consumption of probiotic yoghurt was
reported to improve gastrointestinal symptoms, nutritional intake and tolerance
to antiretroviral treatment among a sample of people living with HIV in Mwanza,