Does stress influence sleep patterns, food intake, weight gain, abdominal obesity and weight loss interventions and vice versa?

Decades of research have reported only weak associations between the intakes of specific foods or drinks and weight gain and obesity. Randomized controlled dietary intervention trials have only shown very modest effects of changes in nutrient intake and diet composition on body weight in obese subjects. This review summarizes the scientific evidence on the role mental stress (either in or not in association with impaired sleep) may play in poor sleep, enhanced appetite, cravings and decreased motivation for physical activity. All these factors contribute to weight gain and obesity, possibly via decreasing the efficacy of weight loss interventions. We also review evidence for the role that lifestyle and stress management may play in achieving weight loss in stress-vulnerable individuals with overweight.

Protein restriction, glomerular filtration rate and albuminuria in patients with type 2 diabetes mellitus: a randomized trial.

OBJECTIVE: Protein restriction delays the progression of non-diabetic and type 1 diabetic renal disorders. This study assessed whether protein restriction delays the onset or early progression of renal disorders in type 2 diabetes. DESIGN: Randomized controlled trial. Outcomes were albuminuria (mg/24 h) and, as an estimate of the glomerular filtration rate, cimetidine-influenced creatinine clearance. SETTING: Primary care. SUBJECTS: Patients with type 2 diabetes and microalbuminuria or at least detectable albuminuria, or a diabetes duration >5 y. INTERVENTIONS: The experimental group received dietary counselling on protein restriction (n=63); a control group (n=68) received the usual dietary advice. The duration of intervention and follow-up was 28+/-7 months. RESULTS: After 6 months, protein intake differed only by 0.08 g/kg/day between the study groups. Subsequently, this difference decreased and eventually disappeared. An initial effect of protein restriction on albuminuria in favor of the experimental group was not sustained, and the glomerular filtration rate decreased in the experimental group at a 1.6+/-2.2 ml/min/1.73 m(2) y lower rate than in the control group (P=0.5). Comparison of patients in the experimental group with a decrease in protein intake of at least 0.20 g/kg/day, with controls with no decrease, indicated a similarly small and insignificant effect on glomerular filtration rate. CONCLUSIONS: It is concluded that, in the longer term prevention or delay of renal damage in patients with type 2 diabetes, protein restriction is neither feasible nor efficacious.

Determinants of albuminuria in people with Type 2 diabetes mellitus.

This study sought to identify determinants of albuminuria in people with Type 2 diabetes. In 335 primary care patients, we assessed albumin-creatinine ratio (ACR) in two 24-h urine samples, and its cross-sectional associations with protein and alcohol intake, cigarette smoking, body weight and height, glycosuria, blood pressure, hypoglycaemic and antihypertensive treatment, gender, age, age at diagnosis, diabetes duration, family history of diabetes and cardiovascular diseases, ethnic origin, and education. The prevalence of micro- or macro-albuminuria (ACR> or =2.0 mg/mmol) was 33%. Among these patients, compared to those with normo-albuminuria, there were more men, protein intake (g/kg) estimated from urinary urea as well as systolic blood pressure and glycosuria were higher, there were more smokers, men were shorter, and a family history of diabetes was less prevalent (all P<0.05). In linear and logistic regression (n=270) albuminuria was independently associated (P<0.05 unless indicated otherwise) with systolic blood pressure (OR(10 mmHg)=1.32), smoking (OR(ex/never)=2.36, OR(current/never)=4.89), glycosuria (OR(> or =7/<1 g/l)=2.41), gender (OR(men/women)=2.50), age in men (OR(10 year)=1.60) (P<0.10) and, inversely, in women (OR(10 year)=0.63) (P>0.10). On aggregation, the modifiable determinants systolic blood pressure, smoking and glycosuria explained 12% of the variation in albuminuria. These factors thus are, although to a moderate extent only, potential determinants of albuminuria. We also observed an independent, inverse association with body height (OR(0.10 m)=0.47). This is in line with the hypothesis that development in utero or during early life influences kidney function in later life.

Adherence to protein restriction in patients with type 2 diabetes mellitus: a randomized trial.

OBJECTIVE: To describe the extent to which diet counselling can decrease protein intake, and to identify predictors of adherence. DESIGN: (1) Randomized trial; (2) observational longitudinal study. SUBJECTS: (1) 125 type 2 diabetic patients in primary care; (2) 59 patients in the experimental group. INTERVENTION: For a period of 12 months, dieticians provided guidance on protein restriction (experimental group, n=59) or the usual dietary advice (control group, n=66). OUTCOME MEASURES: Adherence was estimated primarily from urinary urea excretion (UUE), but also from food-frequency questionnaires (FFQ). RESULTS: After 6 months protein intake was, according to the UUE and the FFQ, respectively, 8 g/day (95% CI -2, 13) (8%) and 15 g/day (95%-CI 9, 22) (16%) lower in the experimental than in the control group. After 12 months these differences were smaller. Linear regression analysis indicated that protein restriction was greater in patients who were well satisfied with their pre-existing diet (r=0.32, bper 1/10=3.6 (1, 6) g), in patients who were less overweight (r=0.32, bper kg.m-2=1.1 (0.2, 2. 0) g), and in patients living alone (r=0.22, b=7.7 (-2, 17) g). These combined factors explained only 11% of variation in adherence. Adherence was not predicted by the number of barriers reported by the patients or by coinciding changes in diet satisfaction. CONCLUSIONS: The diet counselling resulted in a very moderate degree of protein restriction only. Predictors of adherence could be identified, but only a few, and their predictive power was limited.

Reproducibility and biomarker-based validity and responsiveness of a food frequency questionnaire to estimate protein intake.

This study, conducted in the Netherlands in 1994-1996, assessed the reproducibility, validity, and responsiveness of a food frequency questionnaire (FFQ) used with older subjects with type 2 diabetes. During a period of 6 months, 93 subjects had a stable protein intake according to their urinary urea excretion (UUE). An FFQ was completed before and after this period. Reproducibility was evaluated on the basis of the correlation (0.80) between duplicate FFQ estimates of protein intake. At the group level, the smallest detectable difference was 3 g. For 354 subjects, average protein intake according to the FFQ was similar to that from UUE estimates. Validity was evaluated on the basis of the crude and deattenuated correlations, which were 0.31 and 0.39, respectively. The crude correlation was highest for former smokers (r = 0.39) and for patients with a higher body mass index (r = 0.37), and it was very low for current smokers (r = 0.14, p > 0.20). The correlation did not vary with age or gender. Responsiveness was judged on the crude correlation between changes in intake according to the FFQ and UUE; the correlation was 0.22 (n = 134). The responsiveness ratio was 0.73. The authors concluded that FFQ estimates are well reproducible. At the group level, protein intake was estimated correctly, whereas individual protein intake and changes in intake were reflected to a moderate extent only.

The effect of protein restriction on albuminuria in patients with type 2 diabetes mellitus: a randomized trial.

BACKGROUND: A randomized trial was conducted to assess whether protein restriction helps to delay the onset of renal disorders in type 2 diabetic patients. METHODS: Included in the trial were 121 type 2 diabetic patients with microalbuminuria or at least detectable albuminuria, or diabetes of duration > or =5 years. The experimental (39 male/19 female) and control group (35 male/28 female) received counselling on protein restriction and the usual dietary advice, respectively. The outcome measure was albuminuria (mg/24 h). Results. After 6 months in experimental and control groups the change in protein intake was -0.05+/-0.21 and +0.03+/-0.19 g/kg (P = 0.02), and in albuminuria -14% and +11% (P = 0.01), respectively. After 12 months, the differences between the experimental and the control group with respect to both protein intake and albuminuria had decreased. At 6 and 12 months, respectively, albuminuria was 28% (P<0.001) and 18% (P = 0.08) lower in the experimental than the control group. The effect in normoalbuminuric patients did not differ from that in microalbuminuric patients. In the experimental group, blood pressure, HbA1c and body weight decreased; in the control group, such decreases were less or absent. Dose-response analysis showed that a 0.10 g/kg change at 6 months in the intake of protein, of animal protein in particular, was related to an 11.1% change in albuminuria (P<0.005). Combining the intakes at 6 and 12 months suggested a percentage change of 9.1%. CONCLUSIONS: Substantial protein restriction in primary care, type 2 diabetic patients with no nephropathy is barely feasible. However, even a small reduction has a substantial and potentially beneficial effect on albuminuria.

Self-rated health, mortality, and chronic diseases in elderly men. The Zutphen Study, 1985-1990.

The value of self-rated health in predicting mortality and the incidence of chronic diseases was studied in a cohort of 783 elderly Dutch men in the Zutphen Study. In 1985, 48% of the men felt "healthy," while 12% felt "moderately healthy" or "not healthy." As of 1990, 23% of the 783 men had died. Survival analysis showed that self-rated health was highly predictive of subsequent 5-year mortality from all causes (p < 0.001). When adjusted for the presence of major chronic diseases, age, medication use, smoking, alcohol consumption, physical activity, body mass index, systolic blood pressure, serum cholesterol, education, marital status, and family history of chronic diseases, the relative risk for "moderately healthy" or "not healthy" men compared with "healthy" men was 2.7 (95% confidence interval (CI) 1.8-4.3). Analysis of cause-specific mortality revealed that self-rated health was associated with cardiovascular mortality (crude relative risk (RR) = 2.7), but this finding resulted mainly from confounding by baseline prevalence of cardiovascular diseases (adjusted RR = 1.9, 95% CI 0.9-3.8). However, self-rated health was an independent risk factor for cancer mortality (adjusted RR = 4.2, 95% CI 1.9-9.4) and mortality due to other causes (adjusted RR = 3.0, 95% CI 1.2-7.8). Self-rated health did not independently predict the incidence of chronic diseases. This suggests that self-rated health especially affects fatality from chronic diseases rather than their onset, and this issue should be pursued further.

Effect of two-day temperature exposure of neonatal broiler chicks on growth performance and body composition during two weeks at normal conditions.

Newly hatched chicks were allotted to five different climatic treatment groups (28 to 32, 32 to 34, 34 to 35, 35 to 37, and 37 to 40 C) for 2 days after hatch during which feed and water were withheld. Their performance was measured for 2 wk and compared with control chicks kept under normal conditions. During the 2 days of climatic treatment, chicks lost weight of 5.3, 5.4, 6.7, 8.5, and 10.1 g, respectively, but control chicks grew 16.0 g. During 14 days of feed intake, chicks of the highest treatment group grew significantly less (217.5 g) than controls (267.7 g). Also, feed intake was significantly lower (292 versus 386 g). In the group exposed to 37 to 40 C, feed conversion decreased significantly from 1.43 to 1.37 g:g and mortality increased to more than 49%. Body composition of DM, protein, fat, and ash was also estimated. Chicks previously exposed to 37 to 40 C had significantly lower values for the gain in body components: DM (18.49 g), protein (7.13 g), fat (8.75 g), and ash (2.62 g) per chick at 2 wk. The ratios water:protein gain and fat:protein gain after posthatching heat exposure were decreased from 3.82 to 3.45 g:g and .76 to .67 g:g, respectively, whereas the ratio of gain in energy retention:weight gain was similar to that of controls.