Marjanne Senekal

Obesity in South Africa: challenges for government and health professionals

OBJECTIVES To review data on the prevalence, causes and health consequences of obesity in South Africa and propose interventions to prevent and treat obesity and related outcomes. METHODS Data from existing literature were reviewed with an emphasis on changing eating and activity patterns, cultural factors, perceptions and beliefs, urbanisation and globalization. Results of studies on the health consequences of obesity in South Africans are also reviewed. RESULTS Shifts in dietary intakes and activity patterns to higher fat intakes and lower physical activity are contributing to a higher prevalence of obesity. Few overweight black women view themselves as overweight, and some associate thinness with HIV/AIDS. Glucose and lipid toxicity, associated with insulin resistance, play roles in the pathogenesis of the co-morbid diseases of obesity. Elevated free fatty acids in the black population predispose obese black patients to type 2 diabetes. CONCLUSION AND RECOMMENDATIONS Obesity prevention and treatment should be based on education, behaviour change, political support, intersectoral collaboration and community participation, local actions, wide inclusion of the population, adequately resourced programmes, infiltration of existing initiatives, evidence-based planning, and proper monitoring and evaluation. Interventions should have the following components: reasonable weight goals, healthful eating, physical activity and behavioural change. Genes and mutations affecting susceptibility to the development of co-morbidities of obesity and vulnerable periods of life for the development of obesity should be prioritized. Prevention should be managed in community services, identification of high-risk patients in primary healthcare services and treatment of co-morbid diseases in hospital services.

Low Carbohydrate versus Isoenergetic Balanced Diets for Reducing Weight and Cardiovascular Risk: A Systematic Review and Meta-Analysis

Background Some popular weight loss diets restricting carbohydrates (CHO) claim to be more effective, and have additional health benefits in preventing cardiovascular disease compared to balanced weight loss diets. Methods and Findings We compared the effects of low CHO and isoenergetic balanced weight loss diets in overweight and obese adults assessed in randomised controlled trials (minimum follow-up of 12 weeks), and summarised the effects on weight, as well as cardiovascular and diabetes risk. Dietary criteria were derived from existing macronutrient recommendations. We searched Medline, EMBASE and CENTRAL (19 March 2014). Analysis was stratified by outcomes at 3–6 months and 1–2 years, and participants with diabetes were analysed separately. We evaluated dietary adherence and used GRADE to assess the quality of evidence. We calculated mean differences (MD) and performed random-effects meta-analysis. Nineteen trials were included (n = 3209); 3 had adequate allocation concealment. In non-diabetic participants, our analysis showed little or no difference in mean weight loss in the two groups at 3–6 months (MD 0.74 kg, 95%CI −1.49 to 0.01 kg; I2 = 53%; n = 1745, 14 trials; moderate quality evidence) and 1–2 years (MD 0.48 kg, 95%CI −1.44 kg to 0.49 kg; I2 = 12%; n = 1025; 7 trials, moderate quality evidence). Furthermore, little or no difference was detected at 3–6 months and 1–2 years for blood pressure, LDL, HDL and total cholesterol, triglycerides and fasting blood glucose (>914 participants). In diabetic participants, findings showed a similar pattern. Conclusions Trials show weight loss in the short-term irrespective of whether the diet is low CHO or balanced. There is probably little or no difference in weight loss and changes in cardiovascular risk factors up to two years of follow-up when overweight and obese adults, with or without type 2 diabetes, are randomised to low CHO diets and isoenergetic balanced weight loss diets.

The effect of prebiotics on production of antimicrobial compounds, resistance to growth at low pH and in the presence of bile, and adhesion of probiotic cells to intestinal mucus

Aims:  Screening of five bile salt‐resistant and low pH‐tolerant lactic acid bacteria for inhibitory activity against lactic acid bacteria and bacterial strains isolated from the faeces of children with HIV/AIDS. Determining the effect of prebiotics and soy milk‐base on cell viability and adhesion of cells to intestinal mucus.

Evaluation of Body Shape, Eating Disorders and Weight Management Related Parameters in Black Female Students of Rural and Urban Origins:

This study examined body shape dissatisfaction, eating disorder and weight management-related parameters as well as assimilation of Western cultural norms regarding body shape in black female students of urban and rural origins. Subjects (n=180; 20 ± 4,4 years old) were weighed, their height was measured and they completed the Body Shape Questionnaire, EAT-26, Eating Inventory (restraint scale), Adolescent Self-Concept Scale and a questionnaire concerning weight management behaviours. Main findings include lower prevalences of overestimation of body weight and body shape dissatisfaction, similar prevalences for dieting and the use of Hazardous weight reduction methods, and higher prevalences for overweight, obesity, disordered eating attitudes and behaviours, and dietary restraint among subjects than among similar white groups. Furthermore, those with urban origins were more likely to be restrained eaters, to have attempted weight reduction, to aim for weight loss and to fear weight gain. These data indicate that there are signs of more realism concerning weight status among black female students. However, there are also signs of assimilation of Western cultural norms concerning body shape, eating attitudes and behaviours and weight management. This diversity in the black student population in South Africa needs to be recognized when planning interventions to address eating related problems.

The association between the body mass index of first-year female university students and their weight-related perceptions and practices, psychological health, physical activity and other physical health indicators

OBJECTIVE To investigate the association between the weight status of first-year female students (FYFS) and various weight management-related characteristics to identify possible components of a weight management programme for students. DESIGN Cross-sectional study. SETTING Female residences at a South African university. SUBJECTS A total of 360 FYFS. RESULTS Mean (+/-standard deviation (SD)) body mass index (BMI) of the FYFS was 21.8 +/- 2.6 kg m(-2), with 7.2% being underweight, 81.9% normal-weight, 10.0% overweight and 0.8% obese. Underweight, normal-weight and overweight students differed with regard to their perception of their weight (P < 0.001), weight goals (P < 0.001) and previous weight-loss practices (P < 0.001). Mean+/-SD score on the 26-item Eating Attitudes Test (EAT-26) was 8.5 +/- 9.0 with 8.4% classified as high scorers. Mean+/-SD score on the 34-item Body Shape Questionnaire (BSQ) was 87.7 +/- 32.2, with 76.1% classified as low, 11.9% as medium and 11.9% as high scorers. The self-concept questionnaire indicated that 36.7% had a high, 43.9% a medium and 19.4% a low self-concept. Higher BMI correlated with a higher BSQ score (P < 0.001), a lower self-concept (P = 0.029) and a higher EAT-26 score (P < 0.001). Smoking was prevalent amongst 13.1% of students, and 51.2% used vitamin and/or mineral supplements. Students who quitted smoking had higher (P = 0.006) BMI (22.7 +/- 2.9 kg m(-2)) than those who never smoked before (21.6 +/- 2.5 kg m(-2)). Normal-weight students were more physically active than underweight or overweight students (P = 0.038). CONCLUSIONS The specific weight management-related needs of FYFS include information about supplement use, smoking, realistic weight goals, safe and sound weight-loss methods, weight cycling, body-shape perceptions, eating attitudes and behaviours, self-concept and physical activity. Interventions aimed at correcting these problems should target all students, regardless of their BMI.

The accuracy of self-reported weight by overweight and obese women in an outpatient setting

OBJECTIVE To investigate the accuracy of self-reported weight of overweight and obese women and characterisation of under-, correct- and over-reporters based on a number of related variables. DESIGN Weight was self-reported before entering the study. At baseline, actual weight was recorded, and demographic, health, nutritional, psychological and physical activity questionnaires were completed. SETTING A hospital outpatient department. SUBJECTS Participants were 131 women aged 18-64 years with a body mass index attending a Comprehensive Weight Management Programme. OUTCOME MEASURES The accuracy of self-reported weight was investigated for the total group, and the subjects were then categorised into three groups according to accuracy of self-reported weight (under-, correct- and over-reporters). The relationship between these accuracy groups and demographic, health, nutritional, and psychological variables and physical activity was examined, to characterise the under-, correct- and over-reporters. RESULTS Although not statistically significantly different, the total group of women tended to underestimate their weight by 0.8 (+/-3.6) kg. Categorisation according to the accuracy groups revealed that 29% underestimated their weight by 2 kg or more, 19% overestimated their weight by 2 kg or more, and only 52% correctly estimated their weight within 2 kg. Some trends and statistically significant differences between the accuracy groups concerning certain variables, e.g. height, age, income, education, contraceptive pill usage, smoking and food choices were evident. CONCLUSIONS Self-reported weight of a group of overweight/obese individuals may be a valid and reliable indicator of actual weight, but self-reported weight of an overweight/obese individual can not be interpreted similarly. Further research is necessary to ensure reliable characterisation of under-, over- and correct reporters.

Market and product assessment of probiotic/prebiotic-containing functional foods and supplements manufactured in South Africa.

OBJECTIVES Probiotic and prebiotic products manufactured in South Africa were identified and health and content claims stated on the labels were evaluated according to available scientific evidence, the proposed South African regulations in the Foodstuffs, Cosmetics and Disinfectants Act (Act No. 54 of 1972, www.doh.gov.za), and microbial assessment. RESULTS The range of products identified included probiotic- and/or prebiotic-containing supplements (capsules), food items fortified with probiotics and/or prebiotics, and fermented food containing probiotics, e.g. dairy products. Most of the health-related claims on the labels of the identified products do not comply with proposed South African regulations. However, results also indicate that the proposed South African regulations should be reconsidered to include an additional 5 claims, for which scientifically sound evidence is available. The claims regarding probiotic strains, viable cell numbers, prebiotic type and concentration stated on the labels of the products are mostly in line with the proposed South African regulations. The actual viable cell content of 3 out of 5 probiotic supplements readily available on the South African market did not comply with the content claim stated on the label. However, this problem did not seem to affect the inhibitory activity of the probiotic strains against indicator strains isolated from faeces of patients diagnosed with AIDS. To validate this finding in vivo assessments should be implemented before considering the need to include a wider range of prescribed viable cell numbers in the proposed South African regulations. CONCLUSIONS The proposed South African regulations regarding probiotic- and prebiotic-containing products should be revised based on the results of this research, and the manufacturers of these products should be held responsible for providing the consumer with scientifically sound and legally correct information.

A Multidimensional Weight-Management Program for Women

Real and imagined overweight and obesity, and resulting weight-reduction efforts, are associated with the development of a variety of health problems and eating disorders. For many years, research and practice in the field of weight management have been based largely on a unidimensional, simplistic, weight-loss paradigm. The long-term success rate for persons using this paradigm has been low. This article presents a multidimensional paradigm that focuses on all aspects of the prevention, treatment, and management of weight-related problems. The goal is to stimulate a shift from the unidimensional to a more multidimensional approach in weight-management interventions. The paradigm presents weight management as a continuum on which 5 prominent points are identified: formulation of reasonable weight goals, prevention of unnecessary weight; gain or loss, weight loss when necessary, prevention of relapse, and acceptance of an overweight/obese physique when necessary. The intrapersonal characteristics and skills associated with this continuum, namely, self-esteem, body image, self-efficacy, locus of control, motivation, stress management, problem solving and decision making, and assertiveness, as well as the role of stage of change and environmental influences on weight management, are examined. Issues concerning the different dimensions of the paradigm are discussed as are challenges and applications for researchers and practitioners in the field of weight management.

Fat Mass and Obesity-Associated (FTO) Gene Polymorphisms Are Associated with Physical Activity, Food Intake, Eating Behaviors, Psychological Health, and Modeled Change in Body Mass Index in Overweight/Obese Caucasian Adults

The fat mass and obesity-associated (FTO) gene is currently recognized as the most robust predictor of polygenic obesity. We investigated associations between the FTO rs1421085 and rs17817449 polymorphisms and the FTO rs1421085–rs17817449 haplotype and dietary intake, eating behavior, physical activity, and psychological health, as well as the effect of these associations on BMI. N = 133 treatment seeking overweight/obese Caucasian adults participated in this study. Genotyping was performed from whole blood samples. Weight and height was measured and a non-quantified food frequency questionnaire was completed to assess food group intake. Validated questionnaires were completed to assess physical activity (Baecke questionnaire), psychological health (General Health questionnaire, Rosenburg self-esteem scale and Beck Depression Inventory), and eating behavior (Three Factor Eating questionnaire). The risk alleles of the FTO polymorphisms were associated with poorer eating behaviors (higher hunger, internal locus for hunger, and emotional disinhibition scores), a higher intake of high fat foods and refined starches and more depressive symptoms. The modeled results indicate that interactions between the FTO polymorphisms or haplotypes and eating behavior, psychological health, and physical activity levels may be associated with BMI. The clinical significance of these results for implementation as part of weight management interventions needs further investigation.

Vitamin D and Calcium Status in South African Adolescents with Alcohol Use Disorders

Adequate vitamin D and calcium are essential for optimal adolescent skeletal development. Adolescent vitamin D insufficiency/deficiency and poor calcium intake have been reported worldwide. Heavy alcohol use impacts negatively on skeletal health, which is concerning since heavy adolescent drinking is a rising public health problem. This study aimed to examine biochemical vitamin D status and dietary intakes of calcium and vitamin D in 12–16 year-old adolescents with alcohol use disorders (AUD), but without co-morbid substance use disorders, compared to adolescents without AUD. Substance use, serum 25-hydroxyvitamin D (s-25(OH)D) concentrations, energy, calcium and vitamin D intakes were assessed in heavy drinkers (meeting DSM-IV criteria for AUD) (n = 81) and in light/non-drinkers without AUD (non-AUD) (n = 81), matched for age, gender, language, socio-economic status and education. Lifetime alcohol dose was orders of magnitude higher in AUD adolescents compared to non-AUD adolescents. AUD adolescents had a binge drinking pattern and “weekends-only” style of alcohol consumption. Significantly lower (p = 0.038) s-25(OH)D (adjusted for gender, smoking, vitamin D intake) were evident in AUD adolescents compared to non-AUD adolescents. High levels of vitamin D insufficiency/deficiency (s-25(OH)D < 29.9 ng/mL) were prevalent in both groups, but was significantly higher (p = 0.013) in the AUD group (90%) compared to the non-AUD group (70%). All participants were at risk of inadequate calcium and vitamin D intakes (Estimated Average Requirement cut-point method). Both groups were at risk of inadequate calcium intake and had poor biochemical vitamin D status, with binge drinking potentially increasing the risk of the latter. This may have negative implications for peak bone mass accrual and future osteoporosis risk, particularly with protracted binge drinking.