Eating Habits and Illness

The main target of most published research during the 1960s, the 1970s and even the 1980s was the isolated effect of each macronutrient (i.e. carbohydrates, protein or the different types of fat). During the late 1980s and early 1990s the interest shifted to micronutrients with a predominant emphasis on vitamins and antioxidants (carotenoids, tocopherols, vitamin C, selenium) (Martinez 2004). It was noted in the 1970s that developed Western countries have diets high in animal products, fat and sugar, and high rates of cancers of the colorectum, breast and prostate. In contrast, developing countries typically have diets based on one or two starchy staple foods, low intakes of animal products, fat and sugar, low rates of these ‘Western’ cancers, and sometimes high rates of other types of cancer such as cancers of the oesophagus, stomach and liver. Several carefully researched Mediterranean and Asian populations, whose traditional diets consist largely of foods of vegetable origin, show the lowest recorded rates of certain chronic diseases and the highest adult life expectancies (Ortega 2006). Therefore, investigators have focused on environmental factors in attempting to explain temporal trends or international differences in cancer rates. Especially, migrants’ studies strongly suggest that lifestyle-related diets can affect promotion of the aforementioned cancers (Irigaray 2007). For example, colorectal cancer (CRC) rates for Japanese migrants to the United States increased rapidly to surpass the level of the host population. CRC rates for the Japanese in Hawaii and California are now the highest in the world. Rates for this disease have also increased in Japan, presumably as the result of the westernization of the diet (Michels 2003). Some of the main hypotheses that were derived