Carla Gonçalves

Salt reduction in vegetable soup does not affect saltiness intensity and liking in the elderly and children

Study background Reduction of added salt levels in soups is recommended. We evaluated the impact of a 30% reduction of usual added salt in vegetable soups on elderly and childrens saltiness and liking evaluation. Methods Subjects were elderly and recruited from two public nursing homes (29 older adults, 79.7±8.9 years), and preschool children recruited from a public preschool (49 children, 4.5±1.3 years). This study took place in institutional lunchrooms. Through randomization and crossover, the subjects participated in two sensory evaluation sessions, on consecutive days, to assess perceived saltiness intensity (elderly sample) and liking (elderly and children samples) of a vegetable soup with baseline salt content and with a 30% salt reduction. Elderly rated perceived liking through a 10 cm visual analogue scale [‘like extremely’ (1) to ‘dislike extremely’ (10)] and children through a five-point facial scale [‘dislike very much’ (1) to ‘like very much’ (5)]. Results After 30% added salt reduction in vegetable soup, there were no significant differences in saltiness noted by the elderly (p=0.150), and in perceived liking by children (p=0.160) and elderly (p=0.860). Conclusions A 30% salt reduction in vegetable soup may be achieved without compromising perceived saltiness and liking in children and the elderly.

Sodium and potassium urinary excretion and dietary intake: a cross-sectional analysis in adolescents

Background Hypertension is the leading cause for heart disease and stroke, for mortality and morbidity worldwide, and a high sodium-to-potassium intake ratio is considered a stronger risk factor for hypertension than sodium alone. Objective This study aims to evaluate sodium and potassium urinary excretion, and assess the food sources of these nutrients in a sample of Portuguese adolescents. Design A cross-sectional study with a sample of 250 Portuguese adolescents. Sodium and potassium excretion were measured by one 24-h urinary collection, and the coefficient of creatinine was used to validate completeness of urine collections. Dietary sources of sodium and potassium were assessed using a 24-h dietary recall. Results Valid urine collections were provided by 200 adolescents (118 girls) with a median age of 14.0 in both sexes (p=0.295). Regarding sodium, the mean urinary excretion was 3,725 mg/day in boys and 3,062 mg/day in girls (p<0.01), and 9.8% of boys and 22% of girls met the World Health Organization (WHO) recommendations for sodium intake. Concerning potassium, the mean urinary excretion was 2,237 mg/day in boys and 1,904 mg/day in girls (p<0.01), and 6.1% of boys and 1.7% of girls met the WHO recommendations for potassium intake. Major dietary sources for sodium intake were cereal and cereal products (41%), meat products (16%), and milk and milk products (11%); and for potassium intake, main sources were milk and milk products (21%), meat products (17%), and vegetables (15%). Conclusions Adolescents had a high-sodium and low-potassium diet, well above the WHO recommendations. Health promotion interventions are needed in order to decrease sodium and increase potassium intake.

Hydration status using free water reserve in Portuguese adolescents

Introduction: Few data is available about the hydration status of active adolescents in free living conditions. Cell dehydration may be prevalent in healthy, free-living children at school and they could be in a state of chronic voluntary dehydration. Objective: This study aims to describe hydration status assessed by Free Water Reserve (FWR) in adolescents. Method: Two hundred participants (118 girls), aged 13-18 years completed the study. Urinary volume (ml/d) and urinary osmolality (mosm/kg) were measured by one 24h urinary collection, and coefficient of creatinine was used to validate completeness of urine collections. FWR (measured urine volume minus the obligatory urine volume) was used for characterization of hydration status. Positive values of FWR indicate euhydration, negative values the risk of hypo-hydration. Results: Median urinary volume excretion was 1100.0 ml/d for boys and 1025.0 ml/d for girls (p=0.923). Mean urinary osmolality was 715.7±172.3 mosm/kg for boys and 597.42±193.1 mosm/kg for girls (p=0.247). Median FWR (ml/24h) was positive in both sex groups (173.2 ml/d in boys and 373.2 ml/d in girls); however, 40.2% of boys and 31.4% of girls (p=0.195) were at risk of hypo-hydration status. Conclusions: In this sample of adolescents approximately one third was classified as at risk of hypo-hydration status. Preventive measures to increase the level of total water intake should be considered.

Sodium and Potassium Content of Meals Served in University Canteens

A high sodium intake is associated with high blood pressure, an important risk factor for noncommunicable diseases (NCDs). In contrast, the ingestion of high levels of potassium counteracts this negative effect of high sodium intake on blood pressure, thus reducing the sodium-to-potassium ratio. The aim of this work was to determine the sodium and potassium content of meals served in university canteens in Portugal. The analysis included 35 samples of soup and 35 samples of main dish collected at 5 random days from a total of 7 university canteens. The samples were analyzed for sodium and potassium by atomic emission spectrometry technique. On average, a meal (soup and main dish) had a sodium content of 1,069.4 mg (mean sodium content was 671.4 ± 374.5 mg/portion in the main dish and 398.0 ± 153.0 mg/portion in the soup) and a potassium content of 1,004 mg (mean potassium content was 731.4 ± 385.9 mg/serving in the main dish and 272.6 ± 272.6 mg/serving in the soup). Our results revealed that with a single university meal, students can reach 53% of the maximum daily value recommended for sodium and 27% of the minimum daily value recommended for potassium. An investment to decrease sodium and increase potassium in meals served is imperative in order to prevent NCDs.

Beverages intake and hydration status in adolescents

Introduction: Type and quantity of beverages intake among adolescents may influence their hydration status. Objective: To evaluate the association between hydration status assessed by Free Water Reserve (FWR) and consumption of 5 types of beverages (water, milk, soft drinks, fruit juices and hot beverages). Method: Cross-sectional study including 200 participants (118 girls), aged 13-18 years. Urine collections were validated by 24-hour urinary creatinine excretion in relation to body weight according to age group. FWR was assessed for characterization of hydration status (negative values represent risk of hypo-hydration). A 24-hour dietary recall was also collected and data on beverages (g/d) were analyzed from the following groups: water (tap water, natural mineral water, water from a fountain); hot beverages (coffee, tea, beverages made from cereals); milk; juices (home-made juice, bottled juice, nectar without added sugar, other 100% fruit drinks); soft drinks (carbonated and non-carbonated soft-drinks). Mann–Whitney U test was performed to compare ingestion of beverages with FWR status. Results: Median FWR was positive in both sexes (173 ml/d for boys and 373 ml/d for girls); however, 40% of boys and 31% of girls were at risk of hypo-hydration. Mean ingestion of beverages was: water 656±459g/d (n=159), hot beverages 168±200g/d (n=44), milk 489±290g/d (n=165), soft drinks 467±248g/d (n=107) and fruit juices 249±89g/d (n=10). Euhydrated participants reported to drink more water (p=0.009) and hot beverages (p=0.023) than participants at risk of hypo-hydration. Conclusions: In this sample of participants, euhydrated adolescents ingest more water and hot beverages than those at risk of hypo-hydration.