Formulation of the Total Western Diet (TWD) as a Basal Diet for Rodent Cancer Studies

Abstract

Rodent cancer studies typically use defined diets with nutrient profiles optimized for rodent health. However, a defined rodent diet that represents typical American nutrition in all aspects, including calorie sources and macro- and micronutrient composition, is not yet available. Thus, a nutrient density approach was used to formulate the new Total Western Diet (TWD) based on NHANES data for macro- and micronutrient intakes. The TWD has fewer calories from protein and carbohydrate sources and twice that from fat as compared to the AIN-93 diet. The new diet contains more saturated and monounsaturated fats, less polyunsaturated fat, fewer complex carbohydrates, and twice the level of simple sugars. The TWD includes less calcium, copper, folate, thiamin, and vitamins B6, B12, D, and E, but much more sodium. This newly devised diet that better represents typical American nutrition will be highly useful for studies employing animal models of human disease, including cancer.

Effects of Walnut Consumption on Colon Carcinogenesis and Microbial Community Structure

“…AIN-76A diet is a purified diet containing micronutrient profiles optimized for growth and fertility and is widely used in preclinical research to provide "standardized" results among different animal experiments (31). On the other hand, as reported by Hintze and colleagues (14), TWD is formulated to recapitulate the typical American intake of macro-and micronutrients and can be used for dietary chemopreventive studies in rodent models of human disease. Compared with the AIN-76A diet, TWD contains less fat but uses a diverse set of sources to match patterns of fat consumption as reported by the National Health and Nutrition Examination Survey (NHANES), resulting a wide range of dietary fatty acids (14).…”

“…On the other hand, as reported by Hintze and colleagues (14), TWD is formulated to recapitulate the typical American intake of macro-and micronutrients and can be used for dietary chemopreventive studies in rodent models of human disease. Compared with the AIN-76A diet, TWD contains less fat but uses a diverse set of sources to match patterns of fat consumption as reported by the National Health and Nutrition Examination Survey (NHANES), resulting a wide range of dietary fatty acids (14). Interestingly, the TWD diet alone did not cause a significant increase in tumor numbers compared with the AIN-76A diet, which is likely due to the potency of AOM treatment in strain A mice.…”

“…2A). The TWD is a modified diet that contains fat from multiple sources, which can reflect consumption patterns of a typical American (14). All fat sources in the basal diet for each experimental group have been reduced proportionately to contain approximately 35% total fat by calories in the complete diet.…”

“…14). To gain further insight into potential mechanisms by which walnuts may affect colon cancer development, fecal samples were collected to examine dietinduced changes to the community structure of the microbiome.…”

CARD9 Promotes Sex-Biased Colon Tumors in the APCmin Mouse Model

“…Intriguingly, CARD9 has an established role in Candida response (15,22), and simple sugars, prevalent in Western diets, can increase the presence of intestinal Candida (23,24). Although this is just one of many microbes that may enhance CARD9-dependent inflammation, it is an attractive hypothesis that Candida species promote male-specific colorectal cancer associated with Western diets.…”