Y.H. Blauw

Short-term effects of different amounts of sweet and nonsweet carbohydrates on satiety and energy intake

If a sweet taste sensation increases appetite it can be hypothesized that sweet carbohydrates (CHOs) are less satiating than nonsweet CHOs. We studied this hypothesis in two experiments. In two within-subjects repeated measures experiments, subjects (n = 28 in study 1, n = 29 in study 2) got lunches of varying energy content. There were five energy levels (250, 350, 450, 550, and 650 kcal) in the first experiment, and three energy levels (250, 500, and 750 kcal) in the second experiment. Within each energy level there was one lunch with sweet, and one lunch with nonsweet CHOs. The weight, protein, fat, carbohydrate, and fibre level was kept constant within each energy level. The results of the first study confirmed the hypothesis that sweet CHOs were less satiating than nonsweet CHOs. The results of the second study did not show a difference between the satiating effect of sweet and nonsweet CHOs. There was a strong sensory specific effect in both studies. Sweet CHOs had a suppressing effect on appetite for something sweet, whereas nonsweet CHOs suppressed appetite for something savoury. In the second study, sweet CHOs suppressed the intake of sweet food items in a test meal 2 h later in a dose-response manner. Nonsweet CHOs suppressed the intake of nonsweet food items, also in a dose-response manner. It is concluded that energy (or a food property related to energy) has a strong effect on appetite. The taste had a sensory specific effect on subsequent appetite and food selection.

Effect of a nutrient-enriched drink on dietary intake and nutritional status in institutionalised elderly

Objective:(1) To determine whether nutritional supplementation (energy and micronutrients) in institutionalised elderly has a positive effect on dietary intake and nutritional status. (2) To investigate whether individuals tend to compensate for the energy content of the intervention product by decreasing their habitual food consumption.Methods:A 24-week, randomised, double-blind, placebo-controlled, intervention trial in homes for the elderly (n=3), in nursing homes (n=3) and ‘mixed’ homes (n=3) in The Netherlands. Institutionalised elderly people (n=176) older than 60 years of age, with a body mass index ⩽30 kg/m2 and a Mini-Mental State Examination score of 10 points or higher, randomly received a nutrient-enriched drink or a placebo drink twice a day during 24 weeks in addition to their usual diet. Allocation to treatment took into account of sex, the Mini-Mental State Examination score and the plasma homocysteine level. Body weight and several nutrition-related analyses in fasting blood samples were measured in all participants. Data on dietary intake were collected in a subsample (n=66).Results:A significantly favourable effect (P<0.001) of the intervention drink was observed on vitamin intake, mineral intake and vitamin status in blood (for example, homocysteine decreased from 14.7 to 9.5 μmol/l in the intervention group as compared with that in the placebo group (17.2–15.9)). The difference in change in total energy intake between the two treatment groups was 0.8 MJ/day (P=0.166). Energy intake from food decreased in both groups to the same extent (−0.5 MJ/day). Therefore, this decrease cannot be considered as compensation for the energy content of the product.Conclusions:This group of institutionalised elderly people does not compensate for the energy content of a concentrated nutritional supplement. Therefore, this supplement is effective for counteracting the development of malnutrition in this population.

Development and relative validity of a food frequency questionnaire for the estimation of intake of retinol and β‐carotene

The aim of this study was to develop and validate a semiquantitative food frequency questionnaire to classify individuals according to their intakes of retinol and beta-carotene. Food items for the questionnaire were selected both on the basis of their contribution to total population intake of retinol and beta-carotene and on the proportion of between-person variation explained, which was as calculated from data of two study populations in the Netherlands. Thus, 15 products containing retinol and 15 products containing beta-carotene were selected. These contributed over 90% to the total intake and explained 99% of the variation of retinol and beta-carotene, respectively. The questionnaire was validated against a dietary history in a population of 82 women (aged 30-49 years). The time elapsed between the two interviews was (on average) 25 days. Spearman rank-order correlation coefficients comparing the questionnaire with the dietary history were 0.54, 0.59, and 0.64 for retinol, beta-carotene, and total vitamin A, respectively. The proportion of exact agreement in the two extreme categories of vitamin A intake, based on quintiles, was 56%. The corresponding gross misclassification (from 1 extreme category into the opposite) was 3%. These data indicate that a very short questionnaire can classify subjects into categories according to their vitamin A intake.