Increased food energy supply is more than sufficient to explain the US epidemic of obesity

Background: The major drivers of the obesity epidemic are much debated and have considerable policy importance for the population-wide prevention of obesity.

Objective: The objective was to determine the relative contributions of increased energy intake and reduced physical activity to the US obesity epidemic.

Design: We predicted the changes in weight from the changes in estimated energy intakes in US children and adults between the 1970s and 2000s. The increased US food energy supply (adjusted for wastage and assumed to be proportional to energy intake) was apportioned to children and adults and inserted into equations that relate energy intake to body weight derived from doubly labeled water studies. The weight increases predicted from the equations were compared with weight increases measured in representative US surveys over the same period.

Results: For children, the measured weight gain was 4.0 kg, and the predicted weight gain for the increased energy intake was identical at 4.0 kg. For adults, the measured weight gain was 8.6 kg, whereas the predicted weight gain was somewhat higher (10.8 kg).

Conclusions: Increased energy intake appears to be more than sufficient to explain weight gain in the US population. A reversal of the increase in energy intake of 2000 kJ/d (500 kcal/d) for adults and of 1500 kJ/d (350 kcal/d) for children would be needed for a reversal to the mean body weights of the 1970s. Alternatively, large compensatory increases in physical activity (eg, 110–150 min of walking/d), or a combination of both, would achieve the same outcome. Population approaches to reducing obesity should emphasize a reduction in the drivers of increased energy intake.

Modeling response rates in surveys of female sexual difficulty and dysfunction

INTRODUCTION: Studies that address sensitive topics, such as female sexual difficulty and dysfunction, often achieve poor response rates that can bias  results. Factors that affect response rates to studies in this area are not well characterized.
AIM: To model the response rate in studies investigating the prevalence of female sexual difficulty and dysfunction.
METHODS: Databases were searched for English-language, prevalence studies using the search terms: sexual difficulties/dysfunction, woman/women/female, prevalence, and cross-sectional. Studies that did not report response rates or were clinic-based were excluded. A multiple linear regression model was constructed.
MAIN OUTCOME MEASURES: Published response rates.
RESULTS: A total of 1,380 publications were identified, and 54 of these met our inclusion criteria. Our model explained 58% of the variance in response rates of studies investigating the prevalence of difficulty with desire, arousal, orgasm, or sexual pain (R(2) = 0.581, P = 0.027). This model was based on study design variables, study year, location, and the reported prevalence of each type of sexual difficulty. More recent studies (beta = -1.05, P = 0.037) and studies that only included women over 50 years of age (beta = -31.11, P = 0.007) had lower response rates. The use of face-to-face interviews was associated with a higher response rate (beta = 20.51, P = 0.036). Studies that did not include questions regarding desire difficulties achieved higher response rates than those that did include questions on desire difficulty (beta = 23.70, P = 0.034).
CONCLUSION: Response rates in prevalence studies addressing female sexual difficulty and dysfunction are frequently low and have decreased by an average of just over 1% per anum since the late 60s. Participation may improve by conducting interviews in person. Studies that investigate a broad range of ages may be less representative of older women, due to a poorer response in older age groups. Lower response rates in studies that investigate desire difficulty suggest that sexual desire is a particularly sensitive topic.

Taxpayer beliefs and views : two new surveys

The importance of behavioural economics in supplementing and extending the neoclassical analysis of taxpayer behaviour has been recognised for some time. This paper summarises contributions to date and outlines a way forward for integrating the behavioural and neoclassical approaches and developing a more coherent strategy of encouraging taxpayer compliance.The paper then provides significant further evidence relating to taxpayer behaviour by reporting some of the main results of two substantial surveys (N =2,040 and 2,374) of Australian citizens' beliefs, attitudes, values and motivations with respect to the tax system, widely defined. It is concluded that the behaviour of Australian taxpayers is not determined only by considerations of narrow economic rationality based on the expected financial costs and benefits of compliance or non-compliance but is also influenced by a much wider range of factors. Examination of the importance of these other factors might be the most fruitful way of improving tax compliance in the future.

Protein nutrition in fibromyalgia

Background: Fibromyalgia (FM) is a soft-tissue disease of unknown origin. It causes soft-tissue pain and stiffness, often with chronic fatigue, disrupted sleep, headaches and irritable bowel. Fibromyalgia affects an estimated six million Americans of which 80 to 90 percent are female.

Objective: To determine whether dietary intake of protein, Tryptophan, and Branched Chain Amino Acids (BCAA) meet Dietary Reference Intake (DRI) recommendations, and whether there is a difference in animal and vegetable protein intake in subjects with FM compared to healthy controls.

Methods: Thirty subjects with FM and an equal number of controls completed a Food Frequency Questionnaire (FFQ) regarding dietary intake over the previous month. The FFQs were then computer analyzed to determine dietary intake.

Results: Protein intake of all subjects was more than adequate to meet DRI recommendations and there was no significant difference in intake of protein, BCAA, Tryptophan, animal or vegetable protein. Subjects with FM had significantly higher body weight and Body Mass Index (BMI) than controls, and reported having a higher incidence of Irritable Bowel Syndrome (IBS) symptoms than controls.

Conclusion: There was no significant difference in dietary intake of protein, Tryptophan, BCAA, or amounts of animal or vegetable protein in FM subjects compared to healthy controls. Significant differences in body weight and BMI in FM subjects might be related to less physical activity or possibly to malabsorption problems associated with IBS. Malabsorption related to IBS might increase the potential for protein malnutrition, FM, and associated symptoms like chronic fatigue.

Prevalence, awareness, treatment, and control of hypertension in China data from the China National Nutrition and Health Survey 2002

Background— The present article aims to provide accurate estimates of the prevalence, awareness, treatment, and control of hypertension in adults in China.

Methods and Results— Data were obtained from sphygmomanometer measurements and an administered questionnaire from 141 892 Chinese adults 18 years of age who participated in the 2002 China National Nutrition and Health Survey. In 2002, 153 million Chinese adults were hypertensive. The prevalence was higher among men than women (20% versus 17%; P<0.001) and was higher in successive age groups. Overall, the prevalence of hypertension was higher in urban compared with rural areas in men (23% versus 18%; P<0.01) and women (18% versus 16%; P<0.001). Of the 24% affected individuals who were aware of their condition, 78% were treated and 19% were adequately controlled. Despite evidence to suggest improved levels of treatment in individuals with hypertension over the past decade, compared with estimates from 1991, the ratio of controlled to treated hypertension has remained largely unchanged at 1:4.

Conclusions— One in 6 Chinese adults is hypertensive, but only one quarter are aware of their condition. Despite increased rates of blood pressure–lowering treatment, few have their hypertension effectively controlled. National hypertension programs must focus on improving awareness in the wider community, as well as treatment and control, to prevent many tens of thousands of cardiovascular-related deaths.