Prevalence of overweight and obesity in Thai population: results of the National Thai Food Consumption Survey

Overweight and obesity are considered a serious health problem in Thailand. This study examined the prevalence of overweight and obesity in a nationally representative sample of Thai children and adults based on international standards. A cross-sectional population survey of 16,596 Thais aged 3 years and over was conducted. Heights and weights were obtained using standardized methods. Estimates of the overweight and obesity prevalence in children, adolescents, and adults were computed. The prevalence of overweight and obesity among children and adolescents aged 3 to 18 years was 7.6% and 9.0%, respectively, and was higher among boys than girls. Among adults, using the the Regional Office for the Western Pacific (WPRO) standard, 17.1% of adults were classified as overweight [body mass index (BMI) 23.0-24.9 kg/m²], 19.0% as class I obesity (BMI 25.0-29.9 kg/m²), and 4.8% as class II obesity (BMI ≥ 30.0 kg/m²). Using the World Health Organization (WHO) definition, 19.0% were overweight (BMI 25-29.9 kg/m²), 4.0% class I obesity (BMI 30.0-34.9 kg/m²), 0.8% class II obesity (BMI 35.0-39.9 kg/m²), and 0.1% class III obesity (BMI ≥ 40.0 kg/m²). There was a vast difference in obesity prevalence between the WHO and the WPRO criteria. Obesity prevalence when using the WPRO definition (23.8%) was almost five times greater than when defined with the WHO standard (4.9%). The present study found a high prevalence of overweight and obesity in nationally representative sample of the Thai population. Higher rates of overweight and obesity prevalence were computed using the WPRO standard when compared to the WHO standard.

Obesity indices and cardiovascular risk factors in Thai adults

OBJECTIVE

To examine the relationship of body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHpR) and waist-to-height ratio (WHtR) with cardiovascular risk factors and diabetes in Thai population.

DESIGN

A national cross-sectional survey of cardiovascular risk factors.

SUBJECTS

Five thousand and three hundred five Thai adults aged > or =35 years.

MEASUREMENTS

Body weight, height, waist and hip circumference and cardiovascular risk factors including blood pressure, total plasma cholesterol, high-density lipoprotein, triglyceride and fasting plasma glucose were measured. Age- and sex-specific means and prevalence of cardiovascular risk factors were calculated and compared among anthropometric measurements.

RESULTS

There were increasing trends of severity of cardiovascular risk factors and prevalence of morbidity conditions across increasing levels of BMI, WC, WHpR and WHtR categories. For age group > or =65 years, WC, WHpR and WHtR provided more consistent association with cardiovascular risk factors than BMI. Area under the curve indicated that measurement of central obesity could predict cardiovascular risk better than BMI. The optimal cutoff points for anthropometric measurements were in line with the Asia-Pacific recommendation; however, similar cutoff point for men and women between 82 and 85 cm was observed.

CONCLUSION

Central obesity indices were slightly better associated with cardiovascular risk factors compared to BMI in Thai adults aged > or =35 years.

Effects of physical activity and dietary calcium intake on bone mineral density and osteoporosis risk in a rural Thai population

The objective of the study was to determine the effects of modifiable risk factors on bone mineral density in postmenopausal Thai women. Dietary calcium intake (g/day), energy expenditure (kcal/day), and sunlight exposure (h/day) were assessed in 129 rural Thai women aged 63 years (range 50 to 84 years). Bone mineral density (BMD) at the femoral neck, lumbar spine, and distal radius were measured by dual-energy X-ray absorptiometry (DXA). The average dietary calcium intake was 236 +/- 188 g/day (mean +/- SD), while the energy expenditure was 2,118 +/- 656 kcal/day with 1.1 +/- 1.7 h of sunlight exposure. In multiple linear regression analysis, dietary calcium intake, energy expenditure, and years since menopause were significant and independent predictors of BMD at various sites. The three factors together accounted for between 35% and 45% of the variance of BMD. The prevalence of osteoporosis (defined as BMD T-scores < or =-2.5) was 33% at the femoral neck, 42% at the lumbar spine, and 35% at the distal radius. The risk of osteoporosis was higher in women with lower dietary calcium intake (< or =138 mg/day; prevalence rate ratio [PRR], 1.4; 95% confidence interval [CI], 1.0 to 1.9), lower energy expenditure (< or =1,682 kcal; PRR, 1.7; 95% CI, 1.2 to 2.3), and greater years since menopause (> or =6 years; PRR, 2.6; 95% CI, 1.2 to 5.8). The population attributable risk fraction of osteoporosis risk due to the three factors was 70%. These results suggest that in the Thai population, low dietary calcium intake and low physical activity together with advancing years since menopause were independent risk factors for low BMD.

Different mechanism of bone loss in ageing women and men in Khon Kaen Province

The changes of vitamin D status and biochemical markers of bone turnover have been reported with aging. In this study we determined age-related levels of vitamin D and biochemical markers of bone turnover in the general adult population between the ages of 20 and 84 years who were living in Khon Kaen province in northeastern Thailand. Serum 25 hydroxyvitamin D was determined as an indicator of vitamin D status. Serum total alkaline phosphatase and N-terminal mid fragment osteocalcin were measured as biochemical markers of bone formation and serum C-terminal fragment of type I collagen was measured as a marker of bone resorption. The levels of serum 25 hydroxyvitamin D were high in the Khon Kaen population. Men had higher levels of 25 hydroxyvitamin D than did women. However, there were no changes with age in either sex. In women, all biochemical markers of bone turnover increased with age after the fourth decade. The sharp increase was observed in the sixth decade which was around the menopausal age. In contrast, in men all biochemical markers of bone turnover except serum total alkaline phosphatase had a tendency to decrease with age.

CONCLUSION

There was no evidence of vitamin D deficiency in a Khon Kaen population. In addition, serum vitamin D levels did not decline with ageing. Women and men showed different changes of biochemical markers of bone turnover with ageing indicating gender difference in the pathogenesis of osteoporosis.

Elevated serum cholesterol levels in Bangkok children and adolescents

Hypercholesterolemia is a major cardiovascular risk factor. This study aimed to assess serum total cholesterol (TC) levels of children and adolescents living in Bangkok, Thailand. During 1995-1997, nonfasting blood samples were obtained from 570 healthy school children and adolescents aged 9-18 years. The mean TC levels ranged from 143-180 mg/dl in males and from 145-202 mg/dl in females. The prevalences of hypercholesterolemia (TC > or = 200 mg/dl) were 12.2 per cent and 20.3 per cent in males and females, respectively. Twenty-eight per cent of males and 26.9 per cent of females had borderline values (TC 170-199 mg/dl). TC inversely correlated with age (r = -0.16, P < 0.01) in males. The findings indicate that notable percentage of these children had elevated cholesterol levels and warrant additional study concerning risk factors and tracking of lipoprotein levels from childhood into adulthood.