Low glycaemic index or low glycaemic load diets for people with overweight or obesity.

BACKGROUND: The prevalence of obesity is increasing worldwide, yet nutritional management remains contentious. It has been suggested that low glycaemic index (GI) or low glycaemic load (GL) diets may stimulate greater weight loss than higher GI/GL diets or other weight reduction diets. The previous version of this review, published in 2007, found mainly short-term intervention studies. Since then, randomised controlled trials (RCTs) with longer-term follow-up have become available, warranting an update of this review. OBJECTIVES: To assess the effects of low glycaemic index or low glycaemic load diets on weight loss in people with overweight or obesity. SEARCH METHODS: We searched CENTRAL, MEDLINE, one other database, and two clinical trials registers from their inception to 25 May 2022. We did not apply any language restrictions. SELECTION CRITERIA: We included RCTs with a minimum duration of eight weeks comparing low GI/GL diets to higher GI/GL diets or any other diets in people with overweight or obesity. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. We conducted two main comparisons: low GI/GL diets versus higher GI/GL diets and low GI/GL diets versus any other diet. Our main outcomes included change in body weight and body mass index, adverse events, health-related quality of life, and mortality. We used GRADE to assess the certainty of the evidence for each outcome. MAIN RESULTS: In this updated review, we included 10 studies (1210 participants); nine were newly-identified studies. We included only one study from the previous version of this review, following a revision of inclusion criteria. We listed five studies as 'awaiting classification' and one study as 'ongoing'. Of the 10 included studies, seven compared low GI/GL diets (233 participants) with higher GI/GL diets (222 participants) and three studies compared low GI/GL diets (379 participants) with any other diet (376 participants). One study included children (50 participants); one study included adults aged over 65 years (24 participants); the remaining studies included adults (1136 participants). The duration of the interventions varied from eight weeks to 18 months. All trials had an unclear or high risk of bias across several domains.  Low GI/GL diets versus higher GI/GL diets Low GI/GL diets probably result in little to no difference in change in body weight compared to higher GI/GL diets (mean difference (MD) -0.82 kg, 95% confidence interval (CI) -1.92 to 0.28; I2 = 52%; 7 studies, 403 participants; moderate-certainty evidence). Evidence from four studies reporting change in body mass index (BMI) indicated low GI/GL diets may result in little to no difference in change in BMI compared to higher GI/GL diets (MD -0.45 kg/m2, 95% CI -1.02 to 0.12; I2 = 22%; 186 participants; low-certainty evidence)at the end of the study periods. One study assessing participants' mood indicated that low GI/GL diets may improve mood compared to higher GI/GL diets, but the evidence is very uncertain (MD -3.5, 95% CI -9.33 to 2.33; 42 participants; very low-certainty evidence). Two studies assessing adverse events did not report any adverse events; we judged this outcome to have very low-certainty evidence. No studies reported on all-cause mortality.    For the secondary outcomes, low GI/GL diets may result in little to no difference in fat mass compared to higher GI/GL diets (MD -0.86 kg, 95% CI -1.52 to -0.20; I2 = 6%; 6 studies, 295 participants; low certainty-evidence). Similarly, low GI/GL diets may result in little to no difference in fasting blood glucose level compared to higher GI/GL diets (MD 0.12 mmol/L, 95% CI 0.03 to 0.21; I2 = 0%; 6 studies, 344 participants; low-certainty evidence).  Low GI/GL diets versus any other diet Low GI/GL diets probably result in little to no difference in change in body weight compared to other diets (MD -1.24 kg, 95% CI -2.82 to 0.34; I2 = 70%; 3 studies, 723 participants; moderate-certainty evidence). The evidence suggests that low GI/GL diets probably result in little to no difference in change in BMI compared to other diets (MD -0.30 kg in favour of low GI/GL diets, 95% CI -0.59 to -0.01; I2 = 0%; 2 studies, 650 participants; moderate-certainty evidence). Two adverse events were reported in one study: one was not related to the intervention, and the other, an eating disorder, may have been related to the intervention. Another study reported 11 adverse events, including hypoglycaemia following an oral glucose tolerance test. The same study reported seven serious adverse events, including kidney stones and diverticulitis. We judged this outcome to have low-certainty evidence. No studies reported on health-related quality of life or all-cause mortality. For the secondary outcomes, none of the studies reported on fat mass. Low GI/GL diets probably do not reduce fasting blood glucose level compared to other diets (MD 0.03 mmol/L, 95% CI -0.05 to 0.12; I2 = 0%; 3 studies, 732 participants; moderate-certainty evidence).  AUTHORS' CONCLUSIONS: The current evidence indicates there may be little to no difference for all main outcomes between low GI/GL diets versus higher GI/GL diets or any other diet. There is insufficient information to draw firm conclusions about the effect of low GI/GL diets on people with overweight or obesity. Most studies had a small sample size, with only a few participants in each comparison group. We rated the certainty of the evidence as moderate to very low. More well-designed and adequately-powered studies are needed. They should follow a standardised intervention protocol, adopt objective outcome measurement since blinding may be difficult to achieve, and make efforts to minimise loss to follow-up. Furthermore, studies in people from a wide range of ethnicities and with a wide range of dietary habits, as well as studies in low- and middle-income countries, are needed.

Diversity of protein food sources, protein adequacy and amino acid profiles in Indonesia diets: Socio-Cultural Research in Protein Transition (SCRiPT).

The ongoing nutrition transition in lower- and middle-income countries (LMIC) in South East Asia may have a positive impact on protein nutrition. This study assessed the diversity of plant and animal protein food sources in relation to essential amino acid (EAA) adequacy in a population-based sample (N 1665) in Indonesia. Dietary intakes from in-person 24 h recalls provided data on energy and protein intakes (in g/d) from plants (grains, legumes), meat, poultry and fish, and eggs and dairy. Protein diversity scores were based on the number of protein food sources over 24 h. EAA scores were the ratio of amino acid intakes to recommended values. Protein diversity and EAA scores were then compared across multiple socio-demographic indices. Analysis of variance and χ 2 tests were used to test for differences among groups. Energy intakes were 1678 kcal/d for men and 1435 kcal/d for women. Average protein intakes (and prevalence of inadequacy) were 59⋅4 g/d (41⋅7 %) for men and 51⋅5 g/d (51⋅1 %) for women. In regression analyses, higher protein diversity scores were associated with higher protein intakes, more animal protein and less plant protein and with higher EAA scores. Lower protein diversity scores were associated with lower intakes of lysine, leucine and valine relative to requirements, as well as with lower EAA, rural settings, less wealth and less modernisation. Greater diversity of animal protein food sources, observed among groups of higher socio-economic status, was linked to better amino acid adequacy and protein nutrition.

Utilising a Real-Time Continuous Glucose Monitor as Part of a Low Glycaemic Index and Load Diet and Determining Its Effect on Improving Dietary Intake, Body Composition and Metabolic Parameters of Overweight and Obese Young Adults: A Randomised Controlled Trial.

A randomised controlled trial to measure the effects of integrating real-time continuous glucose monitor (rtCGM) into a low glycaemic index (GI) and glycaemic load (GL) dietary intervention on dietary intake, body composition and specific metabolic parameters was carried out. A total of 40 overweight young adults [(means ± SD) age: 26.4 ± 5.3 years, BMI: 29.4 ± 4.7 kg/m2] were randomised into an intervention and control groups for a period of eight weeks. Both groups received nutrition education on low GI and GL foods. The intervention group also received an rtCGM system to monitor their glucose levels 24 h a day. While controlling for physical activities and GI and GL nutrition knowledge, the results indicated that the rtCGM system further improved body weight, BMI, fat mass, fasting plasma glucose, HbA1c, total cholesterol, HDL cholesterol and LDL cholesterol in the intervention group (p < 0.05). This trial unveils the robustness of the rtCGM where non-diabetic overweight and obese young adults can benefit from this device and utilise it as a management tool for overweight and obesity and a primary prevention tool for type 2 diabetes, as it provides real-time and personalised information on physiological changes.

Use of a Continuous Glucose Monitor to Determine the Glycaemic Index of Rice-Based Mixed Meals, Their Effect on a 24 h Glucose Profile and Its Influence on Overweight and Obese Young Adults' Meal Preferences.

Postprandial hyperglycaemia is associated with an increased risk of type-2 diabetes. This study aims to determine the glycaemic index (GI) of three varieties of rice-based mixed meals and their effects on glycaemic variability (GV), 24 h mean glucose levels and target ranges, and rice variety preferences among overweight and obese young adults using real-time continuous glucose monitoring (rtCGM). In a randomised controlled crossover design, 14 participants (22.8 ± 4.6 years, 32.9 ± 5.8 kg/m2) were randomly assigned to receive 3 rice-based mixed meals containing 50 g of available carbohydrates (white rice meal = WRM; brown rice meal = BRM; and parboiled basmati rice meal = PBRM) and 50 g of a glucose reference drink on alternate days. GI, GV, 24 h mean glucose levels and target ranges were measured. Rice variety preferences were compared with those of baseline data and determined at the end of the study period. Results: The analysis found that PBRM was low in GI (45.35 ± 2.06), BRM medium in GI (56.44 ± 2.34), and WRM high in GI (83.03 ± 2.19). PBRM had a significantly (p < 0.05) lower 24 h mean glucose level, higher in-target 24 h glucose level percentage and non-significantly (p > 0.05) lower GV compared to WRM. Prior to observing their postprandial glucose levels generated by rtCGM, the participants preferred WRM (64.3%) over other meals, whereas this preference changed significantly (p < 0.05) at the endpoint (PBRM, 71.4%). PBRM reduced 24 h glucose level and GV of overweight and obese young adults. The rtCGM is proven to be reliable in measuring GI, while providing robust continuous glycaemic information. This may serve as an educational tool that motivates eating behaviour changes among overweight and obese young adults.

Animal and Plant Protein Food Sources in Indonesia Differ Across Socio-Demographic Groups: Socio-Cultural Research in Protein Transition in Indonesia and Malaysia.

BACKGROUND: Plant-based diets in lower-income countries are often associated with inadequate protein nutrition and adverse health outcomes. OBJECTIVE: To examine the diversity of protein food sources, in both animal and plant, across diverse socio-demographic groups in Indonesia as compared to Malaysia. DESIGN: The SCRiPT (Socio Cultural Research in Protein Transition) study was based on population-based samples recruited in Indonesia (N = 1665) and in Malaysia (N = 1604). Data from 24-h in-person dietary recalls in each country were used to construct the frequency counts of protein sources by food group. Protein sources were defined as fish, poultry, red meat (beef, pork, and mutton), eggs, dairy, and plants (cereals, pulses, and tubers). The percent reported frequencies for animal and plant proteins were compared across socio-demographic strata and by country. Analyses were based on one-way Anovas and general linear model regressions adjusting for covariates. RESULTS: Animal protein frequency counts were 34% of total in Indonesia, but 50% in Malaysia's. Higher reported consumption frequencies for poultry and red meat in both countries were associated with urban living, greater modernization, and higher socioeconomic status, with stronger social gradients observed in Indonesia. Reported fish consumption was higher in Indonesia than in Malaysia. Fish was more likely to be listed by rural island populations in Indonesia and was associated with lower education and incomes. Consumption frequencies for plant-based proteins were associated with lower socio-economic status in Indonesia and in Malaysia. CONCLUSIONS: More affluent groups in both countries reported higher frequencies for meat, eggs, and dairy as opposed to fish. Greater economic development in Southeast (SE) Asia is associated with more animal protein, particularly from poultry, which may displace fish, the traditional source of high quality protein for the region.

Simultaneous coffee caffeine intake and sleep deprivation alter glucose homeostasis in Iranian men: a randomized crossover trial.

BACKGROUND AND OBJECTIVES: Sleep deprivation and coffee caffeine consumption have been shown to affect glucose homeostasis separately, but the combined effects of these two variables are unknown. METHODS AND STUDY DESIGN: Forty-two healthy Iranian men, aged 20-40 years old, were assigned to three groups in a randomised crossover trial involving three treatments with two-week washout periods. Subjects were moderate coffee consumers (<=3 cups/day), and had a Pittsburgh Sleep Quality Index <=5. Each treatment involved three nights of deprived sleep (4 hrs. in bed) plus 3×150 cc/cup of boiled water (BW treatment), decaffeinated coffee (DC treatment, without sugar, 99.9% caffeine-free), and caffeinated coffee (CC treatment, without sugar, 65 mg caffeine/ cup). DC and CC treatments were blinded. At the end of each treatment, fasting serum glucose (using enzyme assays) and insulin (using electrochemiluminescence immunoassay) were measured and, again, two hours after an oral glucose tolerance test (OGTT). Insulin resistance was quantified with the homeostasis model. RESULTS: Repeated measures ANOVA indicated no significant difference between the treatments in fasting serum glucose (p=0.248) or insulin resistance (p=0.079). However, ANOVA demonstrated differences between treatments in fasting serum insulin (p=0.004) and glucose, as well as insulin after OGTT (p<0.001). Pairwise comparisons test (within subjects) showed that the CC treatment yielded higher serum glucose and insulin after OGTT (p<0.001), higher fasting serum insulin (p=0.001), and increased insulin resistance (p=0.039) as compared to the DC treatment. CONCLUSIONS: Thus caffeinated coffee was more adverse for glucose homeostasis compared to decaffeinated coffee in individuals who were simultaneously sleep deprived.

Children's exposure to food advertising on free-to-air television: an Asia-Pacific perspective.

There is an established link between food promotions and children's food purchase and consumption. Children in developing countries may be more vulnerable to food promotions given the relative novelty of advertising in these markets. This study aimed to determine the scope of television food advertising to children across the Asia-Pacific to inform policies to restrict this marketing. Six sites were sampled, including from China, Indonesia, Malaysia and South Korea. At each site, 192 h of television were recorded (4 days, 16 h/day, three channels) from May to October 2012. Advertised foods were categorized as core/healthy, non-core/unhealthy or miscellaneous, and by product type. Twenty-seven percent of advertisements were for food/beverages, and the most frequently advertised product was sugar-sweetened drinks. Rates of non-core food advertising were highest during viewing times most popular with children, when between 3 (South Korea) and 15 (Indonesia) non-core food advertisements were broadcast each hour. Children in the Asia-Pacific are exposed to high volumes of unhealthy food/beverage television advertising. Different policy arrangements for food advertising are likely to contribute to regional variations in advertising patterns. Cities with the lowest advertising rates can be identified as exemplars of good policy practice.

Etiology of Obesity Over the Life Span: Ecological and Genetic Highlights from Asian Countries.

Obesity is a worldwide pandemic, and the prevalence rate has doubled since the 1980s. Asian countries are also experiencing the global epidemic of obesity with its related health consequences. The prevalence of overweight and obesity are increasing at an alarming rate across all age groups in Asia. These increases are mainly attributed to rapid economic growth, which leads to socio-economic, nutrition and lifestyle transitions, resulting in a positive energy balance. In addition, fat mass and obesity-associated gene variants, copy number variants in chromosomes and epigenetic modifications have shown positive associations with the risk of obesity among Asians. In this review highlights of prevalence and related ecological and genetic factors that could influence the rapid rise in obesity among Asian populations are discussed.

Weight status among Iranian adolescents: Comparison of four different criteria.

BACKGROUND: Obesity or being overweight is a major health problem in Iran. Only few studies are available that compare the obesity prevalence by four different available criteria. The aim of this study was to determine the prevalence of overweight and obesity among Isfahani adolescents based on four different definitions. MATERIALS AND METHODS: This cross-sectional study was conducted on 3002 Isfahani students (1377 males; 1625 females) aged 11-18 years. Anthropometric measurements including weight and height were measured and body mass index (BMI) was calculated. Sex-specific BMI-for-age reference data of the Iranian national data, Center for Disease Control data (CDC2000), International Obesity taskforce data (IOTF), and recent World Health Organization (WHO) data was used to define overweight and obesity. RESULTS: The mean age of the studied population was 14.8 years and the mean BMI was 20.3 kg/m(2). Girls were on an average 1.4 years older and had almost one unit higher BMI than boys. Underweight was prevalent among almost 38.5% and 25.5% of adolescents as per WHO2007 and national Iranian cut-off points, respectively. The prevalence rates reached 39.5% and 45.8% by IOTF and CDC2000 criteria, respectively. The highest prevalence of overweight was obtained by IOTF cut-points (30.5%), while CDC2000 criteria, WHO2007, and national Iranian cut-points gave similar prevalence results (4.7%, 4.0%, and 4.4%); 2.4% of the studied population were found to be obese by WHO2007 definition, while this rate was 0.8%, 0.5%, and 0.8% by IOTF, CDC2000, and national Iranian cut-points. CONCLUSION: Almost all definitions revealed coexistence of underweight, overweight, and obesity among Isfahani adolescents. Huge differences exist between different criteria for assessing weight status among children. To understand the best appropriate criteria for Iranian adolescents, future studies should focus on the predictability of obesity related co-morbidities by these criteria.

Colostrum supplementation protects against exercise-induced oxidative stress in skeletal muscle in mice.

BACKGROUND: This study examined the effects of bovine colostrum on exercise -induced modulation of antioxidant parameters in skeletal muscle in mice. Adult male BALB/c mice were randomly divided into four groups (control, colostrum alone, exercise and exercise with colostrum) and each group had three subgroups (day 0, 21 and 42). Colostrum groups of mice were given a daily oral supplement of 50 mg/kg body weight of bovine colostrum and the exercise group of mice were made to exercise on the treadmill for 30 minutes per day. Total antioxidants, lipid hydroperoxides, xanthine oxidase and super oxide dismutase level was assayed from the homogenate of hind limb skeletal muscle. RESULTS: Exercise-induced a significant oxidative stress in skeletal muscles as evidenced by the elevated lipid hydroperoxides and xanthine oxidase levels. There was a significant decrease in skeletal muscle total antioxidants and superoxide dismutase levels. Daily colostrum supplement significantly reduced the lipid hydroperoxides and xanthine oxidase enzyme level and increased the total antioxidant levels in the leg muscle. CONCLUSION: Thus, the findings of this study showed that daily bovine colostrum supplementation was beneficial to skeletal muscle to reduce the oxidant-induced damage during muscular exercise.

The female athlete triad among elite Malaysian athletes: prevalence and associated factors.

Women participating in a wide range of competitive sports are at higher risk of developing eating disorders, menstrual irregularities and osteoporosis, which are generally referred to as the 'female athlete triad'. The objective of this study was to determine the prevalence of female athlete triad and factors associated with this condition among athletes participating in different sports. A total of 67 elite female athletes aged between 13-30 years participated in the study and were subdivided into the 'leanness' and 'non-leanness' groups. Eating disorders were assessed using a body image figure rating and the Eating Disorder Inventory (EDI) with body dissatisfaction (BD), drive for thinness (DT), bulimia (B) and perfectionism (P) subscales. Menstrual irregularity was assessed with a self-reported menstrual history questionnaire. Bone quality was measured using a quantitative ultrasound device at one-third distal radius. Prevalence of the female athlete triad was low (1.9%), but the prevalence for individual triad component was high, especially in the leanness group. The prevalence of subjects who were at risk of menstrual irregularity, poor bone quality and eating disorders were 47.6%, 13.3% and 89.2%, respectively, in the leanness group; and 14.3%, 8.3% and 89.2%, respectively, in the non-leanness group. Since the components of the triad are interrelated, identification of athletes at risk of having any one component of the triad, especially those participating in sports that emphasise a lean physique, is an important aid for further diagnosis.

What's on Malaysian television? - A survey on food advertising targeting children.

The Malaysian government recently introduced a ban on fast food advertisements targeting children on television. This study reports on data covering 6 months of television food advertising targeting children. Six out of seven of the Nation's commercial television networks participated (response rate = 85.7%). Based on reported timings of children's programmes, prime time significantly differed ( p <0.05) between weekdays (mean = 1.89 +/- 0.18 hr) and weekends (mean = 4.61 +/- 0.33 hr). The increased trend during weekends, school vacation and Ramadhan was evident. Over the six-month period, the mean number of food advertisements appearing per month varied greatly between television stations (C = 1104; D = 643; F = 407; B = 327; A = 59; E = 47). Food advertising also increased the most in September (n = 3158), followed by July (n = 2770), August (n = 2431), October (n = 2291), November (n = 2245) and June (n = 2211). Content analysis of advertisements indicated snacks were the highest (34.5%), followed by dairy products (20.3%), sugars and candies (13.4%), biscuits (11.2%), fast food (6.7%), breakfast cereal (6.4%), beverages (4.1%), supplements (0.9%), rice (0.6%), noodles (0.5%), bread (0.3%), miscellaneous and processed foods (0.2%). Paradoxically, we found that the frequency of snack food advertised during children's prime time was 5 times more than fast foods. The sodium content (mean = 620 mg per 100g) of these snack foods was found to be highest.

The nutrition and health transition in Malaysia.

The accelerated phase of industrialisation and urbanisation in recent decades has inevitably brought about changes in the lifestyle of Malaysians. Changes in dietary habits and sedentary lifestyles are known to be associated with changes in health and increased prevalence of chronic diseases in the population. The objective of this paper is to provide a better understanding of the link between demographic variables and food consumption patterns related to the nutrition transition in Malaysia. This review uses various reports and publications from several ministries and selected local studies. The statistics compiled over the last two decades have shown that as the population achieves affluence, intakes of calories, fats and sugars increase, which may account for the substantial increase in food importation bills over the same period. Similarly, the rapid growth of the fast food industry during the last decade has added another dimension to the change in food consumption patterns of Malaysians. With the exception of a study on adolescents, the prevalences of overweight and obesity in children and adults are not strictly comparable due to the difference in body mass index (BMI) cut-off points in children and the study protocol in adults, and hence should not be misinterpreted as trends. The recent recommendation to lower the BMI cut-off points for Asians would only increase the magnitude of the existing prevalence among adults. The need to promote healthy nutrition for the population must be pursued vigorously, as the escalation of nutrition-related chronic degenerative diseases - once an urban phenomenon--has now spread to the rural population at an alarming rate. This paper indicates that the problem is real and needs urgent attention because it may be just the tip of the iceberg.