【文章內(nèi)容簡(jiǎn)介】 population, and there were no notable differences by race or sex (Table 3). Potatoes and salad were more popular among Whites than Blacks. Proportions eating fried potatoes declined with age, while those consuming nonfried potatoes increased (data available on request to author). Dried peas and beans, good sources of fiber, wereeaten by only about 10 percent of the population. About half the population consumed no servings or only one serving of a vegetable (Figure 1). Among those who reported only one serving of a vegetable, salad was the most popular, reported by 39 percent. Twentynine percent consumed a serving of potatoes as their only vegetable, and over half of these servings of potatoes were fried. Among those reporting two servings of a vegetable, some did not achieve variety: 9 percent had two servings of potatoes, 7 percent reported two servings of salad, and 5 percent ate two servings of dried peas and beans. Only slightly more than half of the population (55 percent) had at least one serving of fruit or fruit juice. Of these, 27 percent had juice only, and 45 percent had whole fruit only (data available on request to author). Table 4 shows average intake of dietary fiber, vitamin A, and vitamin C among persons consuming various numbers ofservings of fruit and vegetables. These nutrient levels represent dietary intake from all food sources, but exclude vitamin supplements. Persons who consumed neither fruit nor vegetables had, on average, only grams of fiber in their diet on the recall day, or about onefourth of the 2030 grams remended by the National Cancer The amount of fiber in these selfselected diets increased with the total number of servings of fruit and vegetables consumed, and this increase was similar for both fruit and vegetables. A total of five servings of a bination of fruit and vegetables was associated with an intake of approximately 17 grams of fiber. The remended level of fiber intake was achieved only by those who had three or more servings of both fruit and vegetables, a group representing only 4 percent of the US adult population. In the United States, it is estimated that the usual foods available to consumers provide about half of the total vitamin A activity in the diet as provitamin A carotenoids, found in plant products, and the other half as retinol. 14 Among those eating both fruit and vegetables, the US Remended Daily Allowance (RDA) of 5000 lUs of vitamin A was attained only by those having at least two servings, while five servings of a bination of fruit and vegetables were associated with mean vitamin A intake of about 8000 IUs. If either vegetables or fruit were eaten to the exclusion of the other (true of over half the population), the US RDA was reached only among those having three or more servings. For vitamin C, fruit and vegetables represent the primary source in the US diet,10 and Table 4 shows that fruit in particular is associated with higher intake. Among those consuming no fruit, the US RDA of 60mg was attained only by those who had three or more servings of vegetables. This is notable in view of the fact that 45 percent of the US population consumed no servings of fruit on the day of the survey. Table 5 shows caloric and fat intake by servings of fruit and vegetables. Caloric intake increased as numbers ofservings of either food increased. However, the additional calories were not due to the fruit or vegetables alone, as fat intake also increased substantially. This is presumably due in part to fats such as butter and margarine added to potatoes and other vegetables and to oils in salad dressings。 people who eat more servings of fruit and vegetables may also eat more food in general. The increase in dietary fat intake associated with increased servings of vegetables was greater than that associated with increased servings of fruit (data available on request to author). Those who ate no fruit and three or more servings of vegetables had an average of 95 grams of fat in their diets, while those who ate three servings of fruit and no vegetables had 78 grams.FIGURE 1The top pie chart shows the percentages of individuals who consumed zero, one, two, or three or more servings of vegetables on the recall day. Percentagesare estimates based on data from NHANES II, 1976480. The lower left pie chart displays the type of vegetable consumed by those who consumed only one serving ofa vegetable. The pie chart on the lower right displays the types of vegetables consumed by those who had exactly two servings of a vegetable. The category gardenvegetables includes all vegetables except potatoes, salad, dried peas and beans. Examples are green beans, carrots, and corn. When we express fat as a percent of calories, there was a small increase with increasing vegetable intake, approximately two percentage points from the lowest to the highest serving category. In contrast, with increasing fruit consumption, the percent of calories from fat fell approximately five percentage points from the lowest to the highest consumption category. Percent of calories from saturated fat behaved similarly, reaching its highest value among those who consumed no fruit and two or more vegetables, and its lowest value among those who consumed three or more servings of fruit and no vegetables (data available from authors on request).Although the percent of calories from fat increased slightly with increasing vegetable consumption, this was associated with an increase in the ratio of polyunsaturated fats to saturated fats (P/S ratio), the direction remended by the American Heart Association39。5 (data available from authors on request). This may reflect the use of unsaturated oil in salad dressings. Despite the increase in caloric intake and dietary fat with increasing numbers of servings of fruit and vegetables, there was no associated increase in obesity (data available from authors on request). A monly used measure of obesity, the Quetelet Inde