Caloric intake cancer

Total Caloric Intake. Neither the epidemiological studies nor the experiments in animals permit a clear interpretation of the specific effect of total caloric intake on the risk of cancer. Nonetheless, the studies conducted in animals show that a reduction in the total food intake decreases the age-specific incidence of cancer. The evidence is less clear for human beings ... 

The data on anticancer effects of DR on humans are limited. It has been shown in humans that obese persons subjected to DR have decreased rectal cell proliferation, a biomarker related to colon cancer. In a recent retrospective study in Swedish women, it was noted that women with less caloric intake had substantially lower incidence of breast cancer. These reports indicate that the anticancer effects of DR observed in the experimental models are reproducible in humans. 

Another interesting item supplied is that reducing caloric intake also reduces the chances for cancer. 

In addition to meat consnmption, there is a correlation between a high intake of satnrated or animal fat and an elevated risk of CRC (Potter, 1999 Zock, 2001). Excess caloric intake has also been shown to be a risk factor, possibly due to hyperinsuhneamia associated with excess caloric intake and obesity. Finally, a high level of alcohol intake is also a risk factor for CRC (World Cancer Research Fnnd, 1997). 

As the largest study ever undertaken to study the relationships between dietary habits and disease states including cancer, The European Prospective Investigation into Cancer and Nutrition found a reverse correlation between fluid intake and bladder cancer frequency [30]. As expected, higher caloric intake was correlated with higher incidence of bladder cancer in men older than 60 [31]. Similar results were obtained with fruit and vegetable, green tea polyphenol, and vitamin supplement consumption, despite the fact that the results were sometimes unexpected for different cancer cases [32-34]. 

Due to the resources required, the carcinogenicity of ethanol has been examined in only a few lifetime feeding studies in experimental animals. Ketcham et al (1963) found no increased incidence of cancer in mice fed ethanol in a 20% w/v solution offered in place of the drinking water for up to 15 months. However, the ethanol intake was low when compared to the levels which human alcoholics are able to consume (Scheig, 1970 Patek et al, 1975). For example, no more than 20% of total caloric intake could be obtained from ethanol when provided in the drinking water of experimental rats (Missibeck, 1983). In contrast, alcoholics can consume as much as 50% of their calories from ethanol (Mills et al., 1983). In another study, Schmahl et al. (1965) administered either brandy (38% of caloric intake) or a 25% ethanol solution to rats until their natural death. They found no increase in the incidence of cancer and... 

Dietary fat also shows a positive correlation with age-adjusted mortality from cancer at certain other sites in the body, including the colon, rectum and prostate (Carroll Khor, 1975). It should be noted, however, that other dietary variables, such as caloric intake and intake of animal protein, show similar correlations. This simply reflects the fact that fat intake, caloric intake and animal protein intake in different countries each tend to be correlated with one another. One should therefore be wary of assuming that correlations between dietary variables and cancer mortality imply a causative relationship, unless there is other supporting evidence. 

Caloric intake—Many animal studies have shown that caloric restriction generally inhibits cancer formation and increases life expectancy. Conversely, obesity seems to be associated with uterine (endometrial) and kidney cancer in women. 

A report of the National Cholesterol Education Program (NCEP) indicates that the percentage of total fat in the diet, independent of caloric intake, has not been dociunented to be related to cancer risk in the general population. The Women s Health Initiative Dietary Modification Trial, involving approximately 49,000 subjects, showed that those exposed to dietary intervention including an 8.1% lower fat... 

The possible role of dietary fat on colon carcinogenesis has received support from studies in animal models. In several earlier studies on dietary fat and colon cancer, interpretation of results between high- and low-fat diets was complicated by the use of diets of varying caloric density and confounded by different intakes of other nutrients. However, recent studies in which the intake of all nutrients and total calories were controlled between the high-fat and low-fat groups, indicated that the amount of dietary fat is an important factor in colon carcinogenesis (27). 

---