High-protein Weight-loss Diets: Are They Safe and Do They Work? A Review of the Experimental and 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.     

Low sodium haemodialysis reduces interdialytic fluid consumption but paradoxically increases post-dialysis thirst.

BACKGROUND: Interdialytic weight gain (IDWG) can be reduced by lowering the dialysate sodium concentration ([Na]) in haemodialysis patients. It has been assumed that this is because thirst is reduced, although this has been difficult to prove. We compared thirst patterns in stable haemodialysis patients with high and low IDWG using a novel technique and compared the effect of low sodium dialysis (LSD) with normal sodium dialysis (NSD). METHODS: Eight patients with initial high IDWG and seven with low IDWG completed hourly visual analogue ratings of thirst using a modified palmtop computer during the dialysis day and the interdialytic day. The dialysate [Na] was progressively reduced by up to 5 mmol/l over five treatments. Dialysis continued at the lowest attained [Na] for 2 weeks and the measurements were repeated. The dialysate [Na] then returned to baseline and the process was repeated. RESULTS: Baseline interdialytic day mean thirst was higher than the dialysis day mean for the high IDWG group (49.9+/-14.0 vs 36.2+/-16.6) and higher than the low weight gain group (49.9+/-14.0 vs 34.1+/-14.6). This trend persisted on LSD, but there was a pronounced increase in post-dialysis thirst scores for both groups (high IDWG: 46+/-13 vs 30+/-21; low IDWG: 48+/-24 vs 33+/-18). The high IDWG group demonstrated lower IDWG during LSD than NSD (2.23+/-0.98 vs 2.86+/-0.38 kg; P<0.05). CONCLUSIONS: Our results indicate that patients with high IDWG experience more intense feelings of thirst on the interdialytic day. LSD reduces their IDWG, but paradoxically increases thirst in the immediate post-dialysis period.     

父母亲社会经济状况与低出生体质量儿的相关性探讨

①目的 探讨父母亲社会经济状况与低出生体质量儿发生的关系。②方法 采用病例对照研究方法，对190名低出生体质量儿和750名正常出生体质量儿的父母亲进行了相关因素调查，用Logistic回归分析进行了危险因素分析。③结果 母亲年龄大于35岁、母亲的职业为教师或农民、父亲吸烟、母亲孕期吸烟及年家庭收人低是发生低出生体质量儿的危险因素(OR=1．280～7．290)，母亲身高与低出生体质量儿的发生率呈负相关关系(OR=0．898)。④结论 父母亲的社会经济状况与低出生体质量儿的发生有关。     

硕士生睡眠质量状况及其与心理健康的相关研究

目的了解硕士生睡眠质量状况及其与心理健康的关系;为提高硕士生的睡眠质量和心理健康水平提供参考。方法采用匹兹堡睡眠质量指数(PSQI)和症状自评量表(SCL-90)对高校298名硕士生进行睡眠质量和心理健康调查。结果①以PSQI总分≥8作为判断睡眠质量问题的标准,27.4%的硕士生存在睡眠质量问题,睡眠质量不佳主要体现在日间功能障碍(58.4%)、入睡时间(38.6%)、睡眠质量(31%)和睡眠障碍(19.3%)。②一、二年级与三年级在入睡时间上存在显著差异(P<0.05)。公费和自费硕士生在PSQI总分和睡眠效率上存在显著性差异。文科和理科硕士生在催眠药物和日间功能障碍上存在显著性差异。年龄≥30岁和年龄<30岁的硕士生在睡眠效率上存在显著性差异。③硕士生PSQI总分及大多数成份与SCL-90各因子呈显著正相关(P<0.05)。④不同睡眠质量硕士生的心理健康状况分析显示,睡眠质量好、一般和差的硕士生在SCL-90均分及各因子得分上存在显著性差异。结论研究生睡眠质量不尽人意;睡眠质量与心理健康高度相关。各个部门及研究生自身应该引起高度重视,保证良好睡眠,促进身心健康。     

Effects of weight loss in overweight/obese individuals and long-term lipid outcomes – a systematic review

This paper aims to review the evidence for long‐term effectiveness of weight loss on cholesterol, high‐density lipoprotein (HDL), low‐density lipoprotein (LDL) and triglycerides in overweight/obese people. Current evidence is mostly based on short‐term studies. A systematic review of long‐term lipid outcomes of weight loss in studies published between 1966 and 2001, was conducted. Inclusion criteria included all cohort studies and trials carried out on participants with body mass index of greater than or equal to 28 kg m^?2. Studies had at least two weight change measurements and follow‐up of more than 2 years. Thirteen long‐term studies with a follow‐up of more than 2 years were included. Cholesterol has a significant positive linear relationship with weight change (r = 0.89) where change in weight explains about 80% of the cholesterol difference variation (Adj R² = 0.80). For every 10 kg weight loss a drop of 0.23 mmol L^?1 in cholesterol may be expected for a person suffering from obesity or are grossly overweight. Weight loss has long‐term beneficial effects especially on LDL and cholesterol. Weight loss in obese patients should be encouraged and sustained.     

重庆市正常人群肠道双歧杆菌的定量调查

本文介绍了一种双歧杆菌的选择鉴别培养基,并用该培养基对重庆市正常人群肠道双歧杆菌进行了定量分析,进而确定了正常值,为进一步研究双歧杆菌与人类的健康和疾病以及生态学防治提供了科学依据.同时也显示了正常人类肠道中双收杆菌的含量与年龄及性别无显著差异.     

The Dutch twin register: Growth data on weight and height

As part of a longitudinal developmental study of newborn and young Dutch twins, data on weight and height are collected. Birth weight and height are available for 3275 pairs; data on growth, for 1390 pairs.     

Changes in the mouthful weights of familiar foods with age of five years,eight years and adults

For effective mastication and swallowing, to take optimum mouthful food regularly is necessary. The purpose of this study is to compare the weights and the variance of a mouthful food between children and adults. We studied mouthful weight and the coefficient variation in 5-year-old children (n = 10), 8-year-old children (n = 10) and adults (n = 10) while they were eating rice, bread, sausage and apple on two different days. The test foods were served in random order 2–4 hours after lunch. Each portion was weighed before and after each bite to measure the mouthful weight, and the weight of the last bite of each portion was eliminated from the data. The mean weight and coefficient variation in each subject were calculated. The results showed the mean weight was largest in the adults, intermediate in the 8-year-old children, and smallest in the 5-year-old children for all test foods (ANOVA). Moreover, the mean coefficient variation among the weights of the groups revealed that mouthful weight within an individual varied most widely in the 5-year-old children and most narrowly in the adults, and that 8-year-old children could show the same coefficient variation of mouthful weight as adults in rice and apple (Steel-Dwass test). Our results suggest that mouthful weight becomes larger and more regularly with age.     

Correlations between bone mineral density and demographic, lifestyle, and biochemical variables in community-dwelling Japanese women 69 years of age and over

Introduction A few epidemiologic studies have comprehensively attempted to identify risk factors for low bone mineral density (BMD) in elderly Asian women. The purpose of this study was to identify demographic, lifestyle, and biochemical factors correlated with BMD in elderly Japanese women 69 years of age and over.Methods The study design was cross-sectional. The subjects were 583 ambulatory women aged 69 years and over, and their average age was 74.3 (SD 4.4) years. Predictor variables were age, reproductive history, anthropometric indices, grip strength, calcium intake, lifestyle information, and serum 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D (1,25(OH)₂D), osteocalcin (OC), and undercarboxylated osteocalcin (ucOC) values. The outcome variable was forearm BMD measured with a DTX-200 osteometer.Results Simple linear regression analyses showed that BMD was significantly positively associated with body height, weight, body mass index, grip strength, serum albumin concentration, and “housework,” and negatively associated with age, years since menopause, age at menarche, number of children, serum 1,25(OH)₂D concentration, serum OC concentration, and ucOC concentration. The stepwise multiple regression analysis showed that weight (β=0.00316, SE=0.00028, R²=0.180), age (β=−0.00321, SE=0.00050, R²=0.108), log-transformed serum OC (β=−0.0445, SE=0.0064, R²=0.053), log-transformed serum 1,25(OH)₂D (β=−0.0401, SE=0.0074, R²=0.050), “farmwork” (β=0.00904, SE=0.00426, R²=0.005), and serum 25(OH)D concentration (β=0.000281, SE=0.000120, R²=0.003) were significantly associated with BMD.Conclusion It was concluded that body weight is a major predictor of forearm BMD among the factors measured in this study in independent Japanese women 69 years of age and over and that serum 1,25(OH)₂D concentration may be associated with cortical BMD. Maintenance of body weight is very important for maintaining BMD in this population, unless a large weight aggravates obesity-related diseases. A follow-up study is needed to confirm these findings.