Sook Ling Leong

Faster Self-Reported Speed of Eating Is Related to Higher Body Mass Index in a Nationwide Survey of Middle-Aged Women

This study is the first nationwide population survey to explore the association between speed of eating and degree of obesity. The objective was to cross-sectionally examine the relationship between self-reported speed of eating and body mass index (BMI; calculated as kg/m(2)) in a nationally representative sample of New Zealand women. In May 2009, a sample of 2,500 New Zealand women aged 40 to 50 years was randomly selected from the nationwide electoral rolls. A 66% participation rate was achieved. Potential participants were mailed a self-administered questionnaire containing questions on self-reported speed of eating, demographics, health conditions, menopause status, physical activity, height, and weight. Univariate models were used to examine the associations between demographic, health and behavioral variables, and BMI, while a multivariate model was developed to investigate the relationship between self-reported speed of eating and BMI. After adjusting for age, smoking status, menopause status, thyroid condition, ethnicity, socioeconomic status, and physical activity, BMI statistically significantly increased by 2.8% (95% confidence interval: 1.5% to 4.1%; P<0.001) for each category increase in self-reported speed of eating. Although the direction of causality requires confirmation in longitudinal and randomized intervention studies, the results suggest that faster eating is associated with higher BMI in middle-aged women.

Self-Determined, Autonomous Regulation of Eating Behavior Is Related to Lower Body Mass Index in a Nationwide Survey of Middle-Aged Women

BACKGROUND The associations among peoples level of autonomy in regulating their eating behaviors, food patterns, and degree of obesity have not been investigated in a general adult population. OBJECTIVES Our objectives were to cross-sectionally examine, in a nationally representative sample of adult New Zealand women, the associations between different styles of eating behavior regulation and body mass index (BMI), with specific food and eating habits as hypothesized mediators. DESIGN During May 2009, a sample of 2,500 New Zealand women aged 40 to 50 years was randomly selected from the nationwide electoral rolls. A 66% (n=1,601) participation rate was achieved. Potential participants were mailed a self-administered questionnaire containing the Regulation of Eating Behavior scale, questions on specific food and eating habits (frequency of binge eating, speed of eating, usual daily servings of fruits and vegetables, usual frequency of intake of several high-fat and/or high-sugar foods), and height and weight. STATISTICAL ANALYSES Univariate linear regression models were used to examine the associations among demographic, health and behavioral variables, and BMI. Multivariate linear regression models were developed to investigate the relationships between autonomous and controlled forms of eating behavior regulation and BMI, with specific food and eating habits as mediators. RESULTS After adjusting for potential confounders as well as specific food and eating habits that were potential mediators, BMI was statistically significantly lower by 2% (95% CI -2.7% to -1.4%; P<0.001) for every 10-unit increase in autonomous regulation, and statistically significantly higher by 1.4% (95% CI 0.4% to 2.3%; P=0.005) for every 10-unit increase in controlled regulation. The relationships between autonomous regulation and BMI as well as controlled regulation and BMI were only partially mediated by the specific food and eating habits measured. CONCLUSIONS Although the direction of causality requires confirmation, the results provide support for the applicability of Self-Determination Theory, and suggest that developing more autonomous motivation for eating behavior is likely to facilitate healthier food habits and lower BMI in middle-aged women.

The brain, obesity and addiction: an EEG neuroimaging study

Obesity is among the greatest challenges facing healthcare systems with 20% of the world’s population afflicted. Great controversy exists whether obesity can be regarded as an addictive disorder or not. Recently the Yale Food Addiction Scale questionnaire has been developed as a tool to identify individuals with traits of addiction towards food. Using clinical and source localized EEG data we dichotomize obesity. Brain activity in food-addicted and non-food-addicted obese people is compared to alcohol-addicted and non-addicted lean controls. We show that food addiction shares common neural brain activity with alcohol addiction. This ‘addiction neural brain activity’ consists of the dorsal and pregenual anterior cingulate cortex, parahippocampal area and precuneus. Furthermore, common neural obesity neural brain activity exists as well. The ‘obesity neural brain activity’ consists of dorsal and pregenual anterior cingulate cortex, posterior cingulate extending into the precuneus/cuneus as well as the parahippocampal and inferior parietal area. However food-addicted differ from non-food-addicted obese people by opposite activity in the anterior cingulate gyrus. This food addiction and non-food-addiction obesity dichotomy demonstrates there is at least 2 different kinds of obesity with overlapping network activity, but different in anterior cingulate cortex activity.

Anterior Cingulate Implant for Obsessive-Compulsive Disorder

BACKGROUND Obsessive-compulsive disorder (OCD) is a brain disorder with a lifetime prevalence of 2.3%, causing severe functional impairment as a result of anxiety and distress, persistent and repetitive, unwanted, intrusive thoughts (obsessions), and repetitive ritualized behavior (compulsions). Approximately 40%-60% of patients with OCD fail to satisfactorily respond to standard treatments. Intractable OCD has been treated by anterior capsulotomy and cingulotomy, but more recently, neurostimulation approaches have become more popular because of their reversibility. OBJECTIVE Implants for OCD are commonly being used, targeting the anterior limb of the internal capsula or the nucleus accumbens, but an implant on the anterior cingulate cortex has never been reported. METHODS We describe a patient who was primarily treated for alcohol addiction, first with transcranial magnetic stimulation, then by implantation of 2 electrodes overlying the rostrodorsal part of the anterior cingulate cortex bilaterally. RESULTS Her alcohol addiction developed as she was relief drinking to self-treat her OCD, anxiety, and depression. After the surgical implant, she underwent placebo stimulation followed by real stimulation of the dorsal anterior cingulate cortex, which dramatically improved her OCD symptoms (decrease of 65.5% on the Yale-Brown Obsessive Compulsive Drinking Scale) as well as her alcohol craving (decrease of 87.5%) after 36 weeks of treatment. Although there were improvements in all the scores, there was only a modest reduction in the patients weekly alcohol consumption (from 50 units to 32 units). CONCLUSIONS Based on these preliminary positive results we propose to further study the possible beneficial effect of anterior cingulate cortex stimulation for intractable OCD.

Perceptions and Knowledge of Nuts amongst Health Professionals in New Zealand

Despite their nutritional value, population-level nut consumption remains low. Studies suggest that individuals would eat more nuts on their doctor’s advice, making health professionals potentially important for promoting nut consumption. This cross-sectional study aimed to examine the perceptions and knowledge of nuts and the predictors of nut promotion among health professionals in New Zealand. Dietitians, general practitioners (GPs), and practice nurses were identified from the Electoral Roll and invited to complete a questionnaire (n = 318, 292, and 149 respondents respectively). Over one-fifth of GPs and practice nurses believed that eating nuts could increase blood cholesterol concentrations and cause weight gain. The most common perceptions overall were that nuts are healthy; high in protein, fat, and calories; and are satiating. Nut consumption was recommended for reasons relating to these perceptions and because of nuts’ selenium content. Conversely, reasons for suggesting the consumption of fewer nuts included that they were high in calories and fat, would cause weight gain, and concerns regarding allergies and cost. All groups of health professionals were more likely to promote nut consumption if they perceived nuts to reduce the risk of diabetes (all p ≤ 0.034). Education could improve health professionals’ knowledge regarding the effects of nut consumption on blood cholesterol and body weight, alongside other health benefits, which should improve the advice given to patients and may thereby increase nut consumption.

Allostasis in health and food addiction

Homeostasis is the basis of modern medicine and allostasis, a further elaboration of homeostasis, has been defined as stability through change, which was later modified to predictive reference resetting. It has been suggested that pleasure is related to salience (behavioral relevance), and withdrawal has been linked to allostasis in addictive types. The question arises how the clinical and neural signatures of pleasure, salience, allostasis and withdrawal relate, both in a non-addicted and addicted state. Resting state EEGs were performed in 66 people, involving a food-addicted obese group, a non-food addicted obese group and a lean control group. Correlation analyses were performed on behavioral data, and correlation, comparative and conjunction analyses were performed to extract electrophysiological relationships between pleasure, salience, allostasis and withdrawal. Pleasure/liking seems to be the phenomenological expression that enough salient stimuli are obtained, and withdrawal can be seen as a motivational incentive because due to allostatic reference resetting, more stimuli are required. In addition, in contrast to non-addiction, a pathological, non-adaptive salience attached to food results in withdrawal mediated through persistent allostatic reference resetting.

Speed of eating and 3-year BMI change: a nationwide prospective study of mid-age women

OBJECTIVE To conduct the first nationwide population survey to examine the associations between changes in speed of eating and weight gain over 3 years. The study also explored whether faster eating at baseline was related to healthy-weight women becoming overweight after 3 years. DESIGN Longitudinal. At baseline, participants were randomly selected from a nationally representative sampling frame to participate in a prospective study. Women completed self-administered baseline questionnaires on demographic and health measures. Self-reported speed of eating, smoking status, physical activity, menopause status, and height and weight were collected at baseline and again 3 years later. SETTING Nationwide study, New Zealand. SUBJECTS Women (n 1601) aged 40-50 years were recruited at baseline from New Zealand electoral rolls. RESULTS There was no evidence of associations between 3-year BMI adjusting for baseline BMI and either baseline speed of eating (slower and faster; P=0.524) or change in speed of eating (consistently faster eating, consistently slower eating, slower eating at baseline but not at 3 years, faster eating at baseline but not at 3 years; P=0.845). Of the 488 women with healthy BMI (18.5 to <25.0 kg/m2) at baseline, seventy-seven (15.8%) became overweight (BMI≥25.0 kg/m2) after 3 years. Compared with those who were slower eaters at baseline, faster eating at baseline did not increase the risk of becoming overweight 3 years later (P=0.958) nor did change in speed of eating (P=0.236). CONCLUSIONS Results suggest that once women have reached mid-life, faster eating does not predict further weight gain.

Barriers to and facilitators and perceptions of nut consumption among the general population in New Zealand.

OBJECTIVE Despite considerable evidence supporting the health benefits of regular nut consumption, nut intakes remain lower than recommended among many populations. Understanding how the general population perceives nuts could inform strategies to promote regular nut consumption and increase intakes among the general public. DESIGN Cross-sectional study. Participants were invited to complete a questionnaire which included information on nut consumption and knowledge and perceptions of nuts. SETTING The study was set in New Zealand (NZ). SUBJECTS Participants (n 1600), aged 18 years or over, were randomly selected from the NZ electoral roll. RESULTS A total of 710 participants completed the questionnaire (response rate 44 %). More than half of the respondents believed that nuts are healthy, filling, high in protein and high in fat. The most common reason cited by consumers for eating nuts was taste (86 % for nuts, 85 % for nut butters), while dental issues was the most frequent reason for avoidance. About 40 % of respondents were not aware of the effects of nut consumption on lowering blood cholesterol and CVD risk. CONCLUSIONS Despite overall basic knowledge of the nutritional value of nuts, a substantial proportion of the general population was unaware of the cardioprotective effects of nuts. The present study identified common motivations for eating and avoiding nuts, as well as perceptions of nuts which could affect intake. These should guide the content and direction of public health messages to increase regular nut consumption. The publics knowledge gaps should also be addressed.

Weight-Control Methods, 3-Year Weight Change, and Eating Behaviors: A Prospective Nationwide Study of Middle-Aged New Zealand Women

BACKGROUND The effectiveness of womens weight-control methods and the influences of dieting on eating behaviors remain unclear. OBJECTIVES Our aim was to determine the association of various weight-control methods at baseline with weight change to 3 years, and examine the association between baseline weight-control status (trying to lose weight, trying to prevent weight gain or no weight-control attempts) and changes in intuitive eating and binge eating at 3 years. DESIGN A nationally representative sample of 1,601 New Zealand women (40 to 50 years) was recruited and completed a self-administered questionnaire at baseline regarding use of variety of weight-control methods. Information on demographic characteristics, weight, height, food habits, binge eating, and intuitive eating were collected at baseline and 3 years. STATISTICAL ANALYSES Linear and logistic regression models examined associations between both weight status and weight-control methods at baseline and weight change to 3 years; and baseline weight-control status and change in intuitive eating from baseline to 3 years and binge eating at 3 years. χ(2) tests were used to cross-sectionally compare food habits across the weight status categories at both baseline and 3 years. RESULTS Trying to lose weight and the use of weight-control methods at baseline were not associated with change in body weight to 3 years. There were a few differences in the frequency of consumption of high-energy-density foods between those trying to lose or maintain weight and those not attempting weight control. Trying to lose weight at baseline was associated with a 2.0-unit (95% CI 0.7 to 3.4, P=0.003) reduction in intuitive eating scores by 3 years (potential range=21 to 105), and 224% (odds ratio=3.24; 95% CI 1.69 to 6.20; P<0.001) higher odds of binge eating at 3 years. CONCLUSIONS The apparent ineffectiveness of dieting and weight-control behaviors may reflect misconceptions about what constitutes healthy eating or energy-dense foods. Dieting may reduce womens ability to recognize hunger and satiety cues and place women at increased risk of binge eating.

A randomised, double-blind, placebo-controlled parallel trial of closed-loop infraslow brain training in food addiction

The posterior cingulate cortex (PCC) is involved in food craving in obese food addicted individuals. This randomised, double-blind, placebo-controlled parallel study explored the potential therapeutic effects of infraslow neurofeedback (ISF-NF) on food craving targeting the PCC in obese women with symptoms of food addiction. Participants received six sessions of either ISF-NF (n = 11) or placebo (n = 10) over a three-week period. There were no reported adverse effects. Electrophysiologically, there were significant increases in infraslow activity (p = 0.0002) and infraslow/beta nesting (p < 0.001) in the PCC in the ISF-NF group (mean r = 0.004 ± 0.002) compared to placebo (mean r = 0.02 ± 0.002) two days after the last intervention. Also, there was a significant decrease in different dimensions of state food craving compared to baseline and to placebo. Findings suggest that source localized IFS-NF results in electrophysiological changes and may be associated with reduced food craving. This trial is registered at www.anzctr.org.au, identifier, ACTRN12617000601336. This study was funded by the Otago Medical Research Grant: CT375.