[Underestimation of energy intake in a group of young female university students of Madrid]. / Infravaloración de la ingesta energética en un colectivo de jóvenes universitarias de Madrid.

The validity of estimates of energy intake in a group of young women, and the influence of body mass index (BMI) and concern over bodyweight on such estimates, were determined with the aid of a food record intake. The study subjects were a group of female university students between 20 and 32 years of age. Participants maintained a steady weight over the month-long experimental period. Their energy intake was, therefore, very similar to their theoretical energy expenditure. Discrepancies between intake and expenditure data can be used as an indicator of the degree of over or underestimation of intake. 29.7% of subjects had a BMI < 20 kg/m2, 5.5% showed BMIs of > 25 kg/m2, and none exceeded the lower limit of obesity (BMI > 30 kg/m2). Of those with BMI < 20 kg/m2, no significant differences were seen between intake and expenditure (-2.3%). However, those with BMI > or = 20 kg/m2 showed discrepancies of 10.4%. In those with BMI > 25 kg/m2, this figure rose to 22.2% Concern over bodyweight, and the amount of weight that subjects wished to lose, increased with BMI (r = 0.72). However, even some subjects with BMI < 20 kg/m2 showed a desire to lose some weight (2.1 +/- 1 kg). A tendency was seen for subjects with BMI > or = 20 kg/m2 to underestimate their food intake. This became more obvious with increasing BMI (r = 0.36). This could mean that obese women habitually underestimate food intake; a factor that could invalidate many dietetic studies published to date. In the present group, when BMI did not exceed 24 kg/m2, mean underestimation was 4.8%. However, subjects with BMIs > or = 24 kg/m2 underestimated their intakes by 20.4%. Concern over bodyweight (assessed as kg a subject wished to lose) did not change the observed increase in underestimation with rising BMI. Anxiety, therefore, probably parallels true weight and BMI.

Concern about nutrition and its relation to the food habits of a group of young university students from Madrid (Spain).

The aim of this investigation was to study the relationship between concern about nutrition and food consumption in 533 university students (112 men and 421 women), aged 21.7 +/- 2.1 years old. Fish, dairy products and fruit were consumed in quite satisfactory quantities though cereals and vegetables were consumed less frequently than recommended. Men were found to consume greater quantities of milk, meat, bread and alcoholic drinks, while women ate more fruit and vegetables than men. 35.4% of subjects said they were especially concerned about the intake of fat and cholesterol, 24.5% expressed special interest in weight control and 18.2% recorded worries about the intake of vitamins and minerals. 21.6% of subjects expressed no worries at all. Multiple regression analysis showed no differences in concern about nutrition with respect to the sex or body mass index (BMI) of subjects. However, as age increased, the number of subjects expressing no concern fell whilst worries over the quantity of vitamins and minerals in the diet increased. Worries about bodyweight were found to rise with BMI. However, amongst those who wanted to lose weight, 42.2% of women and 7.4% of men had a BMI < 20 kg/m2. These persons, already very slim (below recommended values), still wished to lose weight and could become susceptible to nutritional imbalances. Relationships between concerns and food habits were scarce. Although fat and cholesterol were a concern in theory, the consumption of foodstuffs such as meat and eggs was quite high. However, relationships were found between concern over the vitamin and mineral content of the diet and the intake of supplements, and concern over bodyweight and intake of products that aid slimming. Nutrition educators may find this information useful in the design of their messages and educational programs.

Estimated energy balance in female university students: differences with respect to body mass index and concern about body weight.

OBJECTIVE: To assess the relationships between concern over bodyweight, anthropometric parameters (both real and ideal) and estimated energy balance. DESIGN: Prospective study. SUBJECTS: 126 young, female university students from Madrid, Spain, between the ages of 19 and 36. MEASUREMENTS: Energy intake was measured by means of a "seven day food record'. Anthropometric data were collected both at the beginning of the study and at 30 d to determine any change in weight. Subjects were grouped with respect to body mass index (BMI) (BMI < 30th percentile, between 30th and 60th percentiles and > or = 60th percentile). Subjects also completed a questionnaire asking if they would like to lose some weight. RESULTS: The concern of these young women about their body image was greater amongst those with higher BMI. However, 31.6% of subjects with BMI falling < 30th percentile (< 20.1 Kg/m2) wished to lose some weight. Though the mean discrepancy between energy intake and estimated energy expenditure was 5.7%, there were great differences with respect to BMI and concern expressed about bodyweight. The declared energy intake was 9.3% greater than estimated energy expenditure in very thin subjects (BMI < 30th percentile) who expressed no desire to lose weight. However, in subjects with BMI between the 30th and 60th percentiles and who wanted to lose weight, declared energy intake was 11.4% below estimated expenditure. Similarly in subjects with BMI > or = 60th percentile, declared energy intake was 15.7% below estimated expenditure. CONCLUSION: In order to gain more exact knowledge of food intake in dietary studies, factors such as subject BMI and desire for a different bodyweight should be taken into account.