Macronutrient Recommendations for Remission and Prevention of Diabetes in Asian Indians Based on a Data-Driven Optimization Model: The ICMR-INDIAB National Study.

OBJECTIVE: To derive macronutrient recommendations for remission and prevention of type 2 diabetes (T2D) in Asian Indians using a data-driven optimization approach. RESEARCH DESIGN AND METHODS: Dietary, behavioral, and demographic assessments were performed on 18,090 adults participating in the nationally representative, population-based Indian Council of Medical Research-India Diabetes (ICMR-INDIAB) study. Fasting and 2-h postglucose challenge capillary blood glucose and glycosylated hemoglobin (HbA1c) were estimated. With HbA1c as the outcome, a linear regression model was first obtained for various glycemic categories: newly diagnosed diabetes (NDD), prediabetes (PD), and normal glucose tolerance (NGT). Macronutrient recommendations were formulated as a constrained quadratic programming problem (QPP) to compute optimal macronutrient compositions that would reduce the sum of the difference between the estimated HbA1c from the linear regression model and the targets for remission (6.4% for NDD and 5.6% for PD) and prevention of progression in T2D in PD and NGT groups. RESULTS: Four macronutrient recommendations (%E- Energy) emerged for 1) diabetes remission in NDD: carbohydrate, 49-54%; protein, 19-20%; and fat, 21-26%; 2) PD remission to NGT: carbohydrate, 50-56%; protein,18-20%; fat, 21-27%; 3 and 4) prevention of progression to T2D in PD and NGT: carbohydrate, 54-57% and 56-60%; protein, 16-20% and 14-17%, respectively; and fat 20-24% for PD and NGT. CONCLUSIONS: We recommend reduction in carbohydrates (%E) and an increase in protein (%E) for both T2D remission and for prevention of progression to T2D in PD and NGT groups. Our results underline the need for new dietary guidelines that recommend appropriate changes in macronutrient composition for reducing the burden due to diabetes in South Asia.

Impact of Lipid Genetic Risk Score and Saturated Fatty Acid Intake on Central Obesity in an Asian Indian Population.

Abnormalities in lipid metabolism have been linked to the development of obesity. We used a nutrigenetic approach to establish a link between lipids and obesity in Asian Indians, who are known to have a high prevalence of central obesity and dyslipidaemia. A sample of 497 Asian Indian individuals (260 with type 2 diabetes and 237 with normal glucose tolerance) (mean age: 44 ± 10 years) were randomly chosen from the Chennai Urban Rural Epidemiological Study (CURES). Dietary intake was assessed using a previously validated questionnaire. A genetic risk score (GRS) was constructed based on cholesteryl ester transfer protein (CETP) and lipoprotein lipase (LPL) genetic variants. There was a significant interaction between GRS and saturated fatty acid (SFA) intake on waist circumference (WC) (Pinteraction = 0.006). Individuals with a low SFA intake (≤23.2 g/day), despite carrying ≥2 risk alleles, had a smaller WC compared to individuals carrying <2 risk alleles (Beta = −0.01 cm; p = 0.03). For those individuals carrying ≥2 risk alleles, a high SFA intake (>23.2 g/day) was significantly associated with a larger WC than a low SFA intake (≤23.2 g/day) (Beta = 0.02 cm, p = 0.02). There were no significant interactions between GRS and other dietary factors on any of the measured outcomes. We conclude that a diet low in SFA might help reduce the genetic risk of central obesity confirmed by CETP and LPL genetic variants. Conversely, a high SFA diet increases the genetic risk of central obesity in Asian Indians.

Carbohydrate profiling & glycaemic indices of selected traditional Indian foods.

Background & objectives: Consumption of high glycaemic index (GI) food is associated with a high risk for diabetes. There is a felt need to understand the GI of common Indian traditional foods using standard GI protocols. The present study was aimed to analyse the carbohydrate profile of common traditional Indian food preparation and to determine their GI using standardized protocols. Methods: Twelve food preparations made of millets, wheat, maize and pulses were evaluated for nutrient composition including detailed carbohydrate profiling and tested for GI in healthy volunteers using standard methodology. Capillary blood glucose responses for the test foods containing 50 g available carbohydrates were recorded and compared to the reference food (50 g glucose). GI was calculated from the incremental area under the curve (IUAC) for the test and reference foods. Results: Available carbohydrate content of the food preparations ranged between 13.6 and 49.4 g per cent. Maize roti showed the highest total dietary fibre (7.5 g%). White chick pea 'sundal' showed highest resistant starch content (3.95 g%). Amongst the 12 test foods, five fell in the high GI category (finger millet balls, sorghum, pearl millet and maize roti), four in the medium GI category (sorghum idli, wheat dosa, methi roti and adai) and three in the low GI category (broken wheat upma, white peas sundal and white chick peas sundal). Interpretation & conclusions: Merely being a whole grain-based food does not qualify for a lower GI. The method of processing, food structural integrity and preparation could influence the GI. The type and quality of fibre are important than the quantity of fibre alone. Judicious planning of accompaniments using low GI legumes may favourably modify the glycaemic response to high GI foods in a meal.

Reproducibility and construct validity of a food frequency questionnaire for assessing dietary intake in rural and urban Asian Indian adults.

BACKGROUND AND OBJECTIVES: To evaluate the reproducibility and construct validity of the Madras Diabetes Research Foundation FFQ (MDRF-FFQ) with biomarkers for its use in epidemiological settings in India. METHODS AND STUDY DESIGN: The MDRF-FFQ was administered to 500 participants representing rural and urban areas of 10 Indian states, twice at an interval of 12 months. Reproducibility was assessed using intra cluster correlation coefficients (ICC). Construct validity of carbohydrate and fat intake was assessed using baseline serum lipids by regression analysis. RESULTS: Reproducibility as measured by ICC was 0.50-0.77 for saturated fatty acids (SFA) and energy in urban and 0.61-0.72 for protein and SFA in rural areas. The ICC for food groups was 0.53-0.77 for whole grains, fruits and vegetables in urban and 0.50-0.89 for animal foods and whole grains in rural areas. After adjusting for potential confounders, carbohydrate intake was positively associated with serum triglycerides (TG) (ß [SE]: +2.3 [0.72] mg/dL; p=0.002) and inversely with high density lipoprotein cholesterol (HDL) (ß [SE]:-0.48 [0.12], p<0.001), while dietary fat and SFA (% Energy) were positively associated with HDL, low density lipoprotein (LDL) and total cholesterol and inversely with TG. CONCLUSIONS: The MDRF-FFQ can be considered as a reliable and valid tool to measure the long-term dietary exposure in respect of macronutrient intakes in Indian populations despite diverse dietary practices.

Development and evaluation of nutritional, sensory and glycemic properties of finger millet (Eleusine coracana L.) based food products.

BACKGROUND AND OBJECTIVES: Finger millet (Eleusine coracana L.) (FM) is rich in dietary fibre and is therefore expected to elicit a lower glycemic response compared to other grains. However, there is little data on the glycemic properties of FM-based products. We evaluated the nutritional, sensory and glycemic properties of decorticated millet with lower polish (DFM-LDP), flakes (FMF), vermicelli (FMV) and extruded snack (FMES) (both FMV and FMES with 7-8% added soluble fibre). METHODS AND STUDY DESIGN: The nutrient contents of the FM products were evaluated by standard AOAC (Association of Official Analytical Chemists) and AACC (American Association of Cereal Chemists) methods. Sensory evaluation was conducted monadically using a 9-point hedonic scale using untrained panel members. GI testing was conducted using a standardized validated protocol. The study was conducted according to the guidelines laid down by the Declaration of Helsinki, and was approved by the Ethics Committee of the Madras Diabetes Research Foundation. RESULTS: The products had dietary fibre (DF) content between 5.8-15.6 g%. FMES was unique in having a very low fat content (0.17%). Evaluation of sensory perception revealed moderate acceptance of millet based products. The glycemic indices (GI) (mean±SEM) of the products were 84.7±7.7%, 82.3±6.4%, 65.5±5.1% and 65.0±6.6% for DFM-LDP, FMF, FMV and FMES respectively. CONCLUSIONS: DFM-LDP and FMF (purely finger millet based products) elicited higher glycemic responses. Comparatively, FMV and FMES (with added functional ingredients) exhibited medium GI values and, are healthier dietary options. It is possible to prepare FM products with lower GI by utilizing functional ingredients.

Comparison of dietary profile of a rural south Indian population with the current dietary recommendations for prevention of non-communicable diseases (CURES 147).

BACKGROUND & OBJECTIVES: Despite the rising prevalence of non-communicable diseases (NCDs) in rural India, data on the dietary profile of the rural Indian population in relation to the recommendations for prevention of NCDs are scarce. This study was conducted to assess the dietary intake of a rural south Indian population in relation to the current dietary recommendations for the prevention of NCDs. METHODS: The dietary profiles of 6907 adults aged ≥ 20 yr, from a cluster of 42 villages in Kancheepuram district of Tamil Nadu State in southern India, were assessed using a validated food frequency questionnaire. RESULTS: The prevalence of general obesity was 27.4 per cent and that of abdominal obesity, 14.0 per cent among this rural population. The median daily energy intake of the population was 2034 (IQR 543) kcals. More than 3/4 th of the calories (78.1%) were provided by carbohydrates. Refined cereals, mainly polished rice, was the major contributor to total calories. About 45 per cent of the population did not meet WHO recommendation for protein due to low intake of pulses, flesh foods and dairy products and more than half (57.1%) exceeded the limit of salt intake; 99 per cent of the population did not meet WHO recommendations for fruits and vegetables and 100 per cent did not meet the requirement of n-3 poly unsaturated fatty acids. INTERPRETATION & CONCLUSIONS: The dietary profile of this rural south Indian population reflected unhealthy choices, with the high consumption of refined cereals in the form of polished white rice and low intake of protective foods like fruits, vegetables, n-3 poly and monounsaturated fatty acids. This could potentially contribute to the increase in prevalence of NCDs like diabetes, hypertension and cardiovascular diseases in rural areas and calls for appropriate remedial action.

Type of vegetable oils used in cooking and risk of metabolic syndrome among Asian Indians.

There is little data on the type of vegetable oil used and the prevalence of metabolic syndrome (MS) in Asian Indians. Food frequency questionnaire was used to document the type of cooking oil in 1875 adults in Chennai city. MS was assessed by new harmonizing criteria. The prevalence of MS was higher among sunflower oil users (30.7%) than palmolein (23.2%) and traditional oil (17.1%, p < 0.001) users. The higher prevalence of MS in sunflower oil group persisted even when stratified according to body mass index, except in obese groups. The risk of MS was further compounded by quantity of refined cereals consumed. Higher LA%E and linoleic acid/alpha-linolenic acid ratio in sunflower oil probably contributes to increased risk of MS.