Daily Allowance (daily + allowance)

Distribution by Scientific Domains


Selected Abstracts


High-protein Weight-loss Diets: Are They Safe and Do They Work?

NUTRITION REVIEWS, Issue 7 2002
A Review of the Experimental, Epidemiologic Data
Recommendations for increased consumption of protein are among the most common approaches of popular or fad diets. This review summarizes the effects of dietary protein on satiety, energy intake, thermogenesis, and weight loss, as well as its effect on a variety of health outcomes in adults. In short-term studies, dietary protein modulates energy intake via the sensation of satiety and increases total energy expenditure by increasing the thermic effect of feeding. Whereas these effects did not contribute to weight and fat loss in those studies in which energy intake was fixed, one ad libitum study does suggest that a high-protein diet results in a greater decrease in energy intake, and therefore greater weight and fat loss. In terms of safety, there is little long-term information on the health effects of high-protein diets. From the available data, however, it is evident that the consumption of protein greater than two to three times the U.S. Recommended Daily Allowance contributes to urinary calcium loss and may, in the long term, predispose to bone loss. Caution with these diets is recommended in those individuals who may be predisposed to nephrolithiasis or kidney disease, and particularly in those with diabetes mellitus. [source]


Dialysis adequacy and nutritional status of hemodialysis patients

HEMODIALYSIS INTERNATIONAL, Issue 1 2008
Fernanda TEIXEIRA NUNES
Abstract To characterize the nutritional status of renal failure patients and its relationship with hemodialysis adequacy measured by Kt/V, a study was carried out with a population of 44 adult patients with renal failure and mean age 51±15 years. Anthropometric data, such as dry weight, height, arm circumference, triceps skinfold thickness, mid-arm muscle circumference, and body mass index were assessed, and biochemical tests were conducted for urea, potassium, creatinine, serum albumin, and phosphorus levels, in addition to hemogram and quarterly urea reduction rate average (Kt/V). In order to evaluate calorie intake, a dietary questionnaire on habitual daily food ingestion was administered, taking into consideration the hemodialysis date. The patients were divided into 2 separate groups for the statistical analysis, with 50% of the patients in each group: A (Kt/V<1.2) and B (Kt/V>1.2). The data were tabulated as mean and standard deviation, with differences tested by Student's t test. The correlations between variables were established by the coefficient p of Pearson. Most of the patients (43%) were considered eutrophic, based on the BMI, and presented inadequate calorie intake, corresponding to 88.5±24% (30.8 kcal/kg actual weight) of the total energy required and adequate protein intake, reaching 109.9±40% of the recommended daily allowance (1.24 g/kg of actual weight). There was a correlation of Kt/V with anthropometric parameters such as body mass index, arm circumference, and mid-arm muscle circumference. The biochemical parameters related to dialysis adequacy were albumin, ferritin, and urea (predialysis). Well-dialyzed patients presented better levels of serum albumin. There was an influence of gender and age on correlations of the analyzed variables. Female and younger patients presented better dialysis adequacy. The dialysis adequacy was related to the nutritional status and influenced by the protein intake and body composition. Gender and age had an important influence in the dialysis adequacy, as men presented lower dialysis adequacy and younger adults presented better dialysis adequacy. Further research is necessary to understand better how to facilitate effective and efficient techniques for the nutritional status assessment of hemodialysis patients. [source]


Retinol Intake and Bone Mineral Density in the Elderly: The Rancho Bernardo Study,

JOURNAL OF BONE AND MINERAL RESEARCH, Issue 8 2002
Joanne H. E. Promislow
Abstract Retinol is involved in bone remodeling, and excessive intake has been linked to bone demineralization, yet its role in osteoporosis has received little evaluation. We studied the associations of retinol intake with bone mineral density (BMD) and bone maintenance in an ambulatory community-dwelling cohort of 570 women and 388 men, aged 55,92 years at baseline. Regression analyses, adjusted for standard osteoporosis covariates, showed an inverse U-shaped association of retinol, assessed by food-frequency questionnaires in 1988,1992, with baseline BMD, BMD measured 4 years later, and BMD change. Supplemental retinol use, reported by 50% of women and 39% of men, was an effect modifier in women; the associations of log retinol with BMD and BMD change were negative for supplement users and positive for nonusers at the hip, femoral neck, and spine. At the femoral neck, for every unit increase in log retinol intake, supplement users had 0.02 g/cm2 (p = 0.02) lower BMD and 0.23% (p = 0.05) greater annual bone loss, and nonusers had 0.02 g/cm2 (p = 0.04) greater BMD and 0.22% (p = 0.19) greater bone retention. However, among supplement users, retinol from dietary and supplement sources had similar associations with BMD, suggesting total intake is more important than source. In both sexes, increasing retinol became negatively associated with skeletal health at intakes not far beyond the recommended daily allowance (RDA), intakes reached predominately by supplement users. This study suggests there is a delicate balance between ensuring that the elderly consume sufficient vitamin A and simultaneously cautioning against excessive retinol supplementation. [source]


Biofortification of lettuce (Lactuca sativa L.) with iodine: the effect of iodine form and concentration in the nutrient solution on growth, development and iodine uptake of lettuce grown in water culture

JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 5 2010
Wim Voogt
Abstract BACKGROUND: Iodine is an essential trace element for humans. Two billion individuals have insufficient iodine intake. Biofortification of vegetables with iodine offers an excellent opportunity to increase iodine intake by humans. The main aim was to study the effect of iodine form and concentration in the nutrient solution on growth, development and iodine uptake of lettuce, grown in water culture. RESULTS: In both a winter and summer trial, dose rates of 0, 13, 39, 65, and 90 or 129 µg iodine L,1, applied as iodate (IO3,) or iodide (I,), did not affect plant biomass, produce quality or water uptake. Increases in iodine concentration significantly enhanced iodine content in the plant. Iodine contents in plant tissue were up to five times higher with I, than with IO3,. Iodine was mainly distributed to the outer leaves. The highest iodide dose rates in both trials resulted in 653 and 764 µg iodine kg,1 total leaf fresh weight. CONCLUSION: Biofortification of lettuce with iodine is easily applicable in a hydroponic growing system, both with I, and IO3,. I, was more effective than IO3,. Fifty grams of iodine-biofortified lettuce would provide, respectively, 22% and 25% of the recommended daily allowance of iodine for adolescents and adults. Copyright © 2010 Society of Chemical Industry [source]


Five-year prospective analysis of dietary intake and clinical status in malnourished cystic fibrosis patients

JOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 4 2003
J. Walkowiak
Abstract Background, Poor growth and malnutrition still pose a problem in cystic fibrosis (CF). The aim of the present study was to assess nutrition, as well as clinical status, of malnourished CF patients during a nutritional care programme. Material and methods, The study comprised 38 CF patients, aged 1,18 years old. The prospective annual assessment of dietary intake and clinical status was carried out during 1994,98. Results, The energy intake increased, in comparison with recommended daily allowances, from 83.6 ± 4.8% in 1994 to 107.9 ± 4.9% in 1998. A similar tendency was observed for the percentage of energy derived from fat (30.3 ± 0.8% versus 35.1 ± 0.8%) and protein (11.4 ± 0.4% versus 13.8 ± 0.4%). In subsequent years of the study, an improvement in the fat profile of the diet (with a higher consumption of polyunsaturated fatty acids) was observed. The observed increase of vitamin A and E consumption was related chiefly to changes in the doses of supplementation. During these 5 years, an improvement in nutritional status (Z-score: height ,1.34 ± 0.13 versus ,1.08 ± 0.14 and weight ,1.40 ± 0.09 versus ,1.12 ± 0.08) and lung function (forced expiratory volume in 1 s: 75.5 ± 2.0% versus 77.8 ± 2.2%) was observed. Conclusion, The nutritional care programme resulted in stable quantitative and qualitative changes in dietary intake. Although the diet does not reach the recommended level of high-energy intake, the positive impact of increasing nutrient intake on the nutritional and clinical status of malnourished CF patients was documented. [source]