Dairy food consumption

The aim of this chapter is to review the current knowledge on dairy food consumption and obesity-related chronic illness. Recent articles published in PubMed and Medline databases were critically appraised to describe the current knowledge and propose directions for future research. 

While the association between dairy food intake and obesity is less clear, observational studies have indicated that dairy food consumption may be protective against the development of metabolic syndrome and type 2 diabetes. Pereira et al. (2002) reported an inverse relationship between dairy product consumption and insulin resistance syndrome in a prospective study of 3157 young adults (18-30 years) with 10 years of follow-up. Further, Mennen et al. (2000) reported that more than four servings of dairy products per day was associated with a nonsignificant inverse association with the metabolic syndrome in women, while a significant association in men was found. 

Massey, L. K. (2001). Dairy food consumption, blood pressure and stroke. J. Nutr. 131, 1875-1878. 

Rosell, M., Hakansson, N. N., and Wolk, A. (2006). Association between dairy food consumption and weight change over 9 y in 19,352 perimenopausal women. Am. J. Clin. Nutr 84, 1481-1488. 

The hypothesis that dairy foods contain a cholesterol-lowering milk factor evolved from the observation that Maasai tribesmen of East Africa have low serum concentrations of cholesterol and a low incidence of cardiovascular disease in spite of their consumption of 4 to 5 liters/day of fermented whole milk (Mann and Spoerry 1974). Subsequently, sufficient amounts of yogurt, as well as unfermented milk (whole, lowfat, skim), were reported to exhibit a hypocholesterolemic effect both in humans and in laboratory animals in several studies (Mann 1977 Howard and Marks 1977, 1979 Nair and Mann 1977 Kritchevsky et al 1979 Richardson 1978 Hussi etal. 1981). However, not all investigators have observed a hypocholesterolemic effect of milk. This inconsistency may be explained in part by differences in the experimental design and in the specific type of dairy food used by investigators. 

PCBs are deposited atmospherically onto plants and waters consumed by animals and fish. Because of their bioaccumulation in the food web, the major resource of non-occupational exposure to these contaminants (> 90%) is via food consumption, particularly fish, meat and dairy products. The half-lives of PCBs are of the order of several years. Since they are apolar and highly lipophilic, the highest concentrations are found in fatty foods, rather than in vegetables cereals and fruits [37]. 

Information on annual per capita food use In the U.S. Is obtained from published (17. 18) and unpublished data from the Economic Research Service of USDA. Quantities are measured of approximately 350 foods that "disappear" Into the food distribution system. The amounts are derived by deducting data on exports, military use, year-end Inventories, and nonfood use from data on production, Imports, and beglnnlng-of-the year Inventories. Because of the complexity of the food distribution system, use of each food Is not measured at the same point In the system. Some foods are In a raw or primary state while others are retail products when their use Is measured. Subsequent losses that occur In processing, marketing, and home use are not taken into consideration. Food supply data used In the preparation of this report reflect, for the first time, revised population estimates for 1970-1981 based on the 1980 Census and revised estimates for fluid milk and cream use from 1909-1981. Dairy product consumption data for 1981 In this paper are preliminary. 

Dairy products group. Zinc provided by the use of dairy products has Increased about 50 percent during the past 70 years (Table IV). The largest amount of zinc contributed by dairy products was 2.8 mg per capita per day In 1945 and 1946. These were the years In which total dairy product consumption was the highest. After a slight decline, the level of zinc from this food group has remained relatively constant since the late 1940 s. 

Even the water we drink contains some sodium but only about 1 percent of our total consumption. Obviously, we don t want to restrict our water drinking. Next, foods in their natural state, even fruits and vegetables and, more notably, dairy foods, provide about 12 percent of our salt intake. Surely, we don t want to eliminate any... 

We consume them directly, combine them with other foods directly or through cooking, convert them into sauces, etc. There seems to be no end to the creative way we utilize and consume fermented dairy products. The lesson is clear, we use these products because we enjoy their odor and taste. In the selection process, their nutritional value is secondary when compared to their flavor. Since food consumption is a necessary part of life, and in most societies food selection is primarily based on hedonics, then a priori, the biological origin of aromas is an important subject. 

Thus, the coplanar PCBs contribute about one third of the total dioxin TEQs in human breast milk. The daily TEQ intake per kg body weight is about 50 times higher in breast-fed infants and 3 times higher in toddlers than in adults. Based on a model that included intake measures, food questioimaires, and national food consumption and contamination data, breast-feeding for 6 months contributed about 12% (boys) or 14% (girls) of the cumulative PCB/dioxin TEQ intake until 25 years of age. In toddlers, dairy products contribute 43% of the PCB-TEQ, meat and meat products contributed 14%, and processed foods 23%. Further information on exposures of children can be found in Section 6.6. 

Milk has been a source for food for humans since the beginning of recorded history. Although the use of fresh milk has increased with economic development, the majority of consumption occurs after milk has been heated, processed, or made into butter. The milk industry became a commercial enterprise when methods for preservation of fluid milk were introduced. The successful evolution of the dairy industry from small to large units of production, ie, the farm to the dairy plant, depended on sanitation of animals, products, and equipment cooling faciUties health standards for animals and workers transportation systems constmction materials for process machinery and product containers pasteurization and sterilization methods containers for distribution and refrigeration for products in stores and homes. 

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