Effect of a low glycaemic index diet on blood glucose in women with gestational hyperglycaemia. A randomized controlled trial investigating the effects of a low-glycemic index diet on pregnancy outcomes in gestational diabetes mellitus. A prospective randomised trial to determine the efficacy of a low glycaemic index diet given in addition to healthy eating and weight loss advice in patients with coronary heart disease. A controlled trial of a high dietary fibre intake in pregnancy--effects on plasma glucose and insulin levels. Effect of a low-glycemic-index diet during pregnancy on obstetric outcomes. The use of low glycaemic index foods improves metabolic control of diabetic patients over five weeks. Effects of a low-glycemic load diet in overweight and obese pregnant women: a pilot randomized controlled trial. Can a low-glycemic index diet reduce the need for insulin in gestational diabetes mellitus? A randomized trial. Long-term dietary treatment with increased amounts of fiber-rich low-glycemic index natural foods improves blood glucose control and reduces the number of hypoglycemic events in type 1 diabetic patients.
The objectives of this pilot study were to determine the feasibility and effect on glycaemic control of a low-glycaemic-index (GI) diet in women with gestational diabetes or impaired glucose tolerance of pregnancy.
                participants, recruited from the Diabetes-in-Pregnancy Clinic of an inner-city teaching hospital serving a predominantly non-Caucasian population, were randomized to a low-GI (n=23) or control (n=24) diet and followed from 28 weeks gestation until delivery. Self-monitored-blood-glucose (SMBG), maternal and infant weight were collected from medical charts. Dietary intakes were assessed using diet records and questionnaires.
                diet GI on control (58, 95% CI: 56,60) was significantly higher than on low-GI (49, 95% CI: 47,51; p=0.001). Glycaemic control improved on both diets, but more postprandial glucose values were within target on low-GI (58.4% of n=1891) than control (48.7% of n=1834; p<0.001). SMBG post-breakfast was directly related to pre-pregnancy BMI in the control, but not the low-GI group (BMI*diet interaction; p=0.021). Participants accepted the study foods and were willing to consume them post-intervention.
                a low-GI diet was feasible and acceptable in this sample and facilitated control of postprandial glucose. A larger study is needed to determine the effect of a low-GI diet on maternal and infant outcomes.
                2010. Published by Elsevier Ireland Ltd. The prevalence of gestational diabetes mellitus (GDM) is rising. There is little evidence to demonstrate the effectiveness of one dietary therapy over another. We aimed to investigate the effect of a low-glycemic index (LGI) versus a conventional high-fiber diet on pregnancy outcomes, neonatal anthropometry, and maternal metabolic profile in GDM.
                Ninety-nine women (age 26-42 years; mean ± SD prepregnancy BMI 24 ± 5 kg/m²) diagnosed with GDM at 20-32 weeks' gestation were randomized to follow either an LGI (n = 50; target glycemic index [GI] ~50) or a high-fiber moderate-GI diet (HF) (n = 49; target GI ~60). Dietary intake was assessed by 3-day food records. Pregnancy outcomes were collected from medical records.
                The LGI group achieved a modestly lower GI than the HF group (mean ± SEM 47 ± 1 vs. 53 ± 1; P < 0.001). At birth, there was no significant difference in birth weight (LGI 3.3 ± 0.1 kg vs. HF 3.3 ± 0.1 kg; P = 0.619), birth weight centile (LGI 52.5 ± 4.3 vs. HF 52.2 ± 4.0; P = 0.969), prevalence of macrosomia (LGI 2.1% vs. HF 6.7%; P = 0.157), insulin treatment (LGI 53% vs. HF 65%; P = 0.251), or adverse pregnancy outcomes.
                In intensively monitored women with GDM, an LGI diet and a conventional HF diet produce similar pregnancy outcomes. Recent epidemiological and prospective trial evidence suggests that consumption of a low glycaemic index (LGI) diet will reduce coronary risk. We hypothesise that introduction of an LGI diet will improve the metabolic profile of patients who have undergone coronary artery bypass grafting.
                We conducted a randomised parallel group trial comparing a control group (n=29, age 61.8+/-9 y), who received currently advocated healthy eating dietary advice only, to an intervention group, who received healthy eating advice emphasising LGI carbohydrates (n=26, age 63.6+/-9.4 y) over a 12-week period in free-living patients with coronary heart disease. Outcome measures included fasting glucose, insulin, total cholesterol, high-density lipoprotein cholesterol, very low-density lipoprotein cholesterol, low density lipoprotein cholesterol and triglycerides.
                A significant lower dietary glycaemic index was achieved in the group assigned to an LGI diet compared to the healthy eating control group (71+/-1 vs 81+/-1); fibre intake was also higher in the LGI group (20+/-1 vs 15+/-1 g). All biochemical markers of glucose and lipid metabolism measured were similar after 12 weeks of the LGI diet or control diet.
                The LGI group achieved a significant LGI and a higher dietary fibre intake. However, there was no measurable significant effect of either the LGI diet or the health eating diet on lipid levels; this may have been hidden by concurrent drug therapy. Non-obese women in the second half of pregnancy were randomised into a control group receiving standard dietary advice and a group advised to make high fibre whole-food substitutions in their diets at every opportunity. Glucose and insulin profiles were performed over 24-h periods at 29 and 35 weeks gestation when the diets were equivalent in available carbohydrate, protein and fat, but the control group ingested 12.4 g dietary fibre/24 h and the high fibre group 51.4 g/24 h. Glucose homeostasis was similar in both groups but there was a significant attenuation of post-prandial insulin secretion in the high fibre group. It is suggested that the characteristic post-prandial peaks of plasma insulin observed in Western pregnant women are an unphysiological response to dietary fibre depletion. Pregnancy is a condition in which the glycemic index (GI) may be of particular relevance because maternal glucose is the main energy substrate for intrauterine growth.
                The aim was to compare the effects of low-GI and conventional dietary strategies on pregnancy outcomes in healthy women. Compliance and acceptability were also investigated.
                The subjects were assigned alternately to receive dietary counseling that encouraged either low-GI (LGI) carbohydrate foods or high-fiber, moderate-to-high GI (HGI) foods and were studied 5 times between <16 wk gestation and delivery. Of the 70 women who met the inclusion criteria, 62 completed the study (32 in the LGI and 30 in the HGI groups). Primary outcomes were measures of fetal size.
                The mean diet GI fell significantly in the LGI group but not in the HGI group. Compared with the LGI group, women in the HGI group gave birth to infants who were heavier (3408 +/- 78 compared with 3644 +/- 90 g; P = 0.051) and had a higher birth centile (48 +/- 5 compared with 69 +/- 5; P = 0.005), a higher ponderal index (2.62 +/- 0.04 compared with 2.74 +/- 0.04; P = 0.03), and a higher prevalence of large-for-gestational age (3.1% compared with 33.3%; P = 0.01). Women in the LGI group found the diet easier to follow.
                Because birth weight and ponderal index may predict chronic disease in later life, a low-GI diet may favorably influence long-term outcomes. The aim of the present study was to determine whether any benefit might occur from lowering the glycaemic index of diet in the medium term in diabetic patients. Eighteen well-controlled diabetic patients (12 Type 1 and 6 Type 2 non-insulin-treated), were assigned to either a high mean glycaemic index or low mean glycaemic index diet for 5 weeks each in a random order using a cross-over design. The two diets were equivalent in terms of nutrient content and total and soluble fibre content. The glycaemic indices were 64 +/- 2 (mean +/- SD) % and 38 +/- 5% for the two diets. The high glycaemic index diet was enriched in bread and potato and the low glycaemic index diet in pasta, rice, and legumes. At the end of the study periods, the following variables were improved on the low compared to the high glycaemic index diet: fructosamine (3.9 +/- 0.9 vs 3.4 +/- 0.4 mmol l-1, p less than 0.05); fasting blood glucose (10.8 +/- 2.8 vs 9.6 +/- 2.7 mmol l-1, p less than 0.02); 2-h postprandial blood glucose (11.6 +/- 2.9 vs 10.3 +/- 2.5 mmol l-1, p less than 0.02); mean daily blood glucose (12.0 +/- 2.5 vs 10.4 +/- 2.7 mmol l-1, p less than 0.02); serum triglycerides (1.5 +/- 0.9 vs 1.2 +/- 0.6 mmol l-1, p less than 0.05). No significant differences were found in body weight, HbA1C, insulin binding to erythrocytes, insulin and drug requirements, and other circulating lipids (cholesterol, HDL-cholesterol, phospholipids, Apolipoprotein A1, Apolipoprotein B). Thus the inclusion of low glycaemic index foods in the diet of diabetic patients may be an additional measure which slightly but favourably influences carbohydrate and lipid metabolism, requires only small changes in nutritional habits and has no known deleterious effects. The optimal diet for pregnancy that is complicated by excessive weight is unknown.
                We aimed to examine the effects of a low-glycemic load (low-GL) diet in overweight and obese pregnant women.
                We randomly assigned 46 overweight or obese pregnant women to receive a low-GL or a low-fat diet. Participants received carbohydrate-rich foods, fats, and snack foods through home delivery or study visits. The primary outcome was birth weight z score. Other endpoints included infant anthropometric measurements, gestational duration, maternal weight gain, and maternal metabolic parameters.
                There were no significant differences in birth weight z score or other measures of infant adiposity between groups. However, in the low-GL compared with the low-fat group, gestational duration was longer (mean ± SD: 39.3 ± 1.1 compared with 37.9 ± 3.1 wk; P = 0.05) and fewer deliveries occurred at ≤ 38.0 wk (13% compared with 48%, P = 0.02; with exclusion of planned cesarean deliveries: 5% compared with 53%; P = 0.002). Adjusted head circumference was greater in the low-GL group (35.0 ± 0.8 compared with 34.2 ± 1.3 cm, P = 0.01). Women in the low-GL group had smaller increases in triglycerides [median (interquartile range): 49 (19, 70) compared with 93 (34, 129) mg/dL; P = 0.03] and total cholesterol [13 (0, 36) compared with 33 (22, 56) mg/dL, P = 0.04] and a greater decrease in C-reactive protein [-2.5 (-5.5, -0.7) compared with -0.4 (-1.4, 1.5) mg/dL, P = 0.007].
                A low-GL diet resulted in longer pregnancy duration, greater infant head circumference, and improved maternal cardiovascular risk factors. Large-scale studies are warranted to evaluate whether dietary intervention during pregnancy aimed at lowering GL may be useful in the prevention of prematurity and other adverse maternal and infant outcomes. This trial is registered at clinicaltrials.gov as NCT00364403. A low-glycemic index diet is effective as a treatment for individuals with diabetes and has been shown to improve pregnancy outcomes when used from the first trimester. A low-glycemic index diet is commonly advised as treatment for women with gestational diabetes mellitus (GDM). However, the efficacy of this advice and associated pregnancy outcomes have not been systematically examined. The purpose of this study was to determine whether prescribing a low-glycemic index diet for women with GDM could reduce the number of women requiring insulin without compromise of pregnancy outcomes.
                All women with GDM seen over a 12-month period were considered for inclusion in the study. Women (n = 63) were randomly assigned to receive either a low-glycemic index diet or a conventional high-fiber (and higher glycemic index) diet.
                Of the 31 women randomly assigned to a low-glycemic index diet, 9 (29%) required insulin. Of the women randomly assigned to a higher-glycemic index diet, a significantly higher proportion, 19 of 32 (59%), met the criteria to commence insulin treatment (P = 0.023). However, 9 of these 19 women were able to avoid insulin use by changing to a low-glycemic index diet. Key obstetric and fetal outcomes were not significantly different.
                Using a low-glycemic index diet for women with GDM effectively halved the number needing to use insulin, with no compromise of obstetric or fetal outcomes. To evaluate in type 1 diabetic patients 1) the long-term feasibility of a high-fiber (HF) diet composed exclusively of natural foodstuffs and 2) the efficacy of this diet in relation to blood glucose control and incidence of hypoglycemic episodes.
                The study was randomized with parallel groups. Participants were part of a larger multicenter study on the effects of acarbose on glucose control in diabetes. A total of 63 type 1 diabetic patients, age 28 +/- 9 years, BMI 24 +/- 0.6 kg/m2, after a 4-week run-in period on their habitual diet, were randomized to either an HF (n = 32) or a low-fiber (LF) diet (n = 31) for 24 weeks. The two diets, composed exclusively of natural foodstuffs, were weight-maintaining and, aside from their fiber content, were similar for all nutrients. At the end of the run-in period and the dietary treatment, fasting blood samples for the measurement of plasma cholesterol, HDL cholesterol, triglyceride, and HbA(1c) were collected. A daily glycemic profile was performed on a day in which the participants had consumed a standard menu representative of their treatment diet (HF or LF).
                Of the 63 study subjects, 29 in the HF group (91%) and 25 in the LF group (81%) completed the study Compared with the LF diet, the HF diet after 24 weeks decreased both mean daily blood glucose concentrations (P < 0.05) and number of hypoglycemic events (P < 0.01). When compliance to diet was taken into account, 83% of the subjects on the HF diet and 88% on the LF diet were compliant. In this subgroup, compared with the LF diet, the HF diet significantly reduced mean daily blood glucose concentrations (P < 0.001), HbA(1c) (P < 0.05), and number of hypoglycemic events (P < 0.01).
                In type 1 diabetic patients, an HF diet is feasible in the long term and, compared with an LF diet, improves glycemic control and reduces the number of hypoglycemic events.
While a low glycaemic index diet was seen to be beneficial for some outcomes for both mother and child, results from the review were inconclusive. Further trials with large sample sizes and longer follow up are required to make more definitive conclusions. No conclusions could be drawn from the high-fibre versus control-diet comparison since the trial involved did not report on many of the outcomes we prespecified.