β-Carotene and Ascorbic Acid Retention in Fresh and Processed Vegetables

In this review of the scientific literature on the relationship between vegetable and fruit consumption and risk of cancer, results from 206 human epidemiologic studies and 22 animal studies are summarized. The evidence for a protective effect of greater vegetable and fruit consumption is consistent for cancers of the stomach, esophagus, lung, oral cavity and pharynx, endometrium, pancreas, and colon. The types of vegetables or fruit that most often appear to be protective against cancer are raw vegetables, followed by allium vegetables, carrots, green vegetables, cruciferous vegetables, and tomatoes. Substances present in vegetables and fruit that may help protect against cancer, and their mechanisms, are also briefly reviewed; these include dithiolthiones, isothiocyanates, indole-3-carbinol, allium compounds, isoflavones, protease inhibitors, saponins, phytosterols, inositol hexaphosphate, vitamin C, D-limonene, lutein, folic acid, beta carotene, lycopene, selenium, vitamin E, flavonoids, and dietary fiber. Current US vegetable and fruit intake, which averages about 3.4 servings per day, is discussed, as are possible noncancer-related effects of increased vegetable and fruit consumption, including benefits against cardiovascular disease, diabetes, stroke, obesity, diverticulosis, and cataracts. Suggestions for dietitians to use in counseling persons toward increasing vegetable and fruit intake are presented. Show more

To determine the proportion of youth meeting national recommendations for food group intake and to identify food intake patterns. The US Department of Agriculture's 1989-1991 Continuing Surveys of Food Intakes by Individuals were used to estimate food intake. Intake was determined from 3 days of diet by disaggregating foods into their component ingredients and using weights that correspond to servings. The sample included 3307 youth, 2 to 19 years of age, living in the 48 conterminous United States. Main Outcome Measures. Mean number of servings and percentage of individuals meeting national recommendations for food group intake according to demographic characteristics, patterns of intake, and nutrient profiles associated with each pattern. Mean numbers of servings per day were below minimum recommendations for all food groups except the dairy group (ages 2 to 11). Percentages of youth meeting recommendations ranged from approximately 30% for fruit, grain, meat, and dairy to 36% for vegetables. Sixteen percent of youth did not meet any recommendations, and 1% met all recommendations. The pattern of meeting all recommendations resulted in nutrient intakes above the recommended dietary allowances and was high in fat. Conversely, meeting none of the recommendations resulted in intakes well below the recommended dietary allowances for some nutrients. Total fat and added sugars averaged 35% and 15% of energy, respectively, and levels were similar among most demographic groups. Children and teens in the United States follow eating patterns that do not meet national recommendations. Nutrition education and intervention are needed among US children. Show more