Hypocaloric diets and ketogenesis in the management of obese gestational diabetic women

From starvation to time-restricted eating: a review of fasting physiology

We have long known that subjects with obesity who fast for several weeks survive. Calculations that assume the brain can only use glucose indicated that all carbohydrate and protein sources would be consumed by the brain within several weeks yet subjects with obesity who fasted for several weeks survived. This anomaly led to the determination of the metabolic role of ketone bodies. Subsequent studies transformed our understanding of ketone bodies and illustrated the value of challenging the norm and adapting theory to evidence. Although prolonged fasting is no longer a treatment for obesity, the early studies of starvation provided valuable insights about macronutrient metabolism and ketone body adaptations that fasting elicits. Intermittent fasting and its variants such as time-restricted eating are fasting models that are far less regimented than starvation and severe calorie restriction; yet they produce metabolic benefits. The mechanisms that produce the metabolic changes that intermittent fasting elicits are relatively unknown. In this article, we review the physiology of starvation, starvation adaptation diets, diet-induced ketosis, and intermittent fasting. Understanding the premise and physiology that these regimens induce is necessary to draw parallels and provoke thoughts on the mechanisms underlying the metabolic benefits of intermittent fasting and its variants.

Gestational Diabetes Mellitus: What Can Medical Nutrition Therapy Do?

Gestational diabetes mellitus (GDM) is one of the common complications during pregnancy. Numerous studies have shown that GDM is associated with a series of adverse effects on both mothers and offspring. Due to the particularity of pregnancy, medical nutrition treatment is considered to be the first choice for the treatment of GDM. This contribution reviews the research progress of medical nutrition treatment in GDM, summarizes the international recommendations on the intake of various nutrients and the influence of nutrients on the prevalence of GDM, and the improvement effect of nutritional intervention on it, in order to provide references for research in related fields of GDM and the targeted development of enteral nutrition.

Knowledge domain and research trends for Gestational Diabetes Mellitus and nutrition from 2011 to 2021: a bibliometric analysis

Objective

Nutrient management and lifestyle changes are the frontlines of treatment for all pregnant women diagnosed with Gestational Diabetes Mellitus (GDM). This study aimed to identify the global research architecture, trends, and hotpots of GDM and nutrition.

Methods

We obtained publications from the sub-databases of Science Citation Index Expanded and Social Science Citation Index sourced from the Web of Science Core Collection database on January 4, 2022, using publication years between 2011 and 2021. CiteSpace software, VOSviewer, and Microsoft Excel 2019 were used to conduct the bibliometric analyses.

Results

A growing publication trend was observed for GDM and nutrition, and this field has great potential. More GDM and nutrition research has been conducted in developed countries than developing countries. The top three authors with a high publication frequency, co-citations, and a good h-index were from the United States. There were the four studies of randomized controlled trials (RCTs) or meta-analyses of RCTs, as well as one review in the top five items of cited literature. Keywords were categorized into four clusters based on the keywords visualization.

Conclusion

It is important to strengthen the collaboration between nations of different economies to produce more high-quality research on GDM and nutrition. It may be beneficial to further study the etiology, diagnosis, and treatment of GDM based on current results to provide a new perspective on GDM and nutrition.

The Role of Lifestyle Interventions in the Prevention and Treatment of Gestational Diabetes Mellitus

Gestational diabetes mellitus (GDM) is one of the most common pregnancy-related endocrinopathies, affecting up to 25% of pregnancies globally. GDM increases the risk of perinatal and delivery complications, and the chance of developing type 2 diabetes mellitus and its complications, including cardiovascular diseases. This elevated risk is then passed on to the next generation, creating a cycle of metabolic dysfunction across generations. For many years, GDM preventive measures have had inconsistent results, but recent systematic reviews and meta-analyses have identified promising new preventative routes. This review aims to summarize the evidence investigating the efficacy of lifestyle treatments for the prevention of GDM and to summarize the effects of two lifestyle interventions, including physical activity and dietary interventions. Based on the present research, future studies should be conducted to investigate whether initiating lifestyle interventions during the preconception period is more beneficial in preventing GDM. In addition, research targeting pregnancy should be designed with a personalized approach. Therefore, studies should customize intervention approaches depending on the presence of modifiable and non-modifiable risk factors at the individual level.

Dietary Advice to Support Glycaemic Control and Weight Management in Women with Type 1 Diabetes during Pregnancy and Breastfeeding

In women with type 1 diabetes, the risk of adverse pregnancy outcomes, including congenital anomalies, preeclampsia, preterm delivery, foetal overgrowth and perinatal death is 2-4-fold increased compared to the background population. This review provides the present evidence supporting recommendations for the diet during pregnancy and breastfeeding in women with type 1 diabetes. The amount of carbohydrate consumed in a meal is the main dietary factor affecting the postprandial glucose response. Excessive gestational weight gain is emerging as another important risk factor for foetal overgrowth. Dietary advice to promote optimized glycaemic control and appropriate gestational weight gain is therefore important for normal foetal growth and pregnancy outcome. Dietary management should include advice to secure sufficient intake of micro- and macronutrients with a focus on limiting postprandial glucose excursions, preventing hypoglycaemia and promoting appropriate gestational weight gain and weight loss after delivery. Irrespective of pre-pregnancy BMI, a total daily intake of a minimum of 175 g of carbohydrate, mainly from low-glycaemic-index sources such as bread, whole grain, fruits, rice, potatoes, dairy products and pasta, is recommended during pregnancy. These food items are often available at a lower cost than ultra-processed foods, so this dietary advice is likely to be feasible also in women with low socioeconomic status. Individual counselling aiming at consistent timing of three main meals and 2-4 snacks daily, with focus on carbohydrate amount with pragmatic carbohydrate counting, is probably of value to prevent both hypoglycaemia and hyperglycaemia. The recommended gestational weight gain is dependent on maternal pre-pregnancy BMI and is lower when BMI is above 25 kg/m2. Daily folic acid supplementation should be initiated before conception and taken during the first 12 gestational weeks to minimize the risk of foetal malformations. Women with type 1 diabetes are encouraged to breastfeed. A total daily intake of a minimum of 210 g of carbohydrate is recommended in the breastfeeding period for all women irrespective of pre-pregnancy BMI to maintain acceptable glycaemic control while avoiding ketoacidosis and hypoglycaemia. During breastfeeding insulin requirements are reported approximately 20% lower than before pregnancy. Women should be encouraged to avoid weight retention after pregnancy in order to reduce the risk of overweight and obesity later in life. In conclusion, pregnant women with type 1 diabetes are recommended to follow the general dietary recommendations for pregnant and breastfeeding women with special emphasis on using carbohydrate counting to secure sufficient intake of carbohydrates and to avoid excessive gestational weight gain and weight retention after pregnancy.

The Carbohydrate Threshold in Pregnancy and Gestational Diabetes: How Low Can We Go?

The original nutrition approach for the treatment of gestational diabetes mellitus (GDM) was to reduce total carbohydrate intake to 33-40% of total energy (EI) to decrease fetal overgrowth. Conversely, accumulating evidence suggests that higher carbohydrate intakes (60-70% EI, higher quality carbohydrates with low glycemic index/low added sugars) can control maternal glycemia. The Institute of Medicine (IOM) recommends ≥175 g/d of carbohydrate intake during pregnancy; however, many women are consuming lower carbohydrate (LC) diets (<175 g/d of carbohydrate or <40% of EI) within pregnancy and the periconceptual period aiming to improve glycemic control and pregnancy outcomes. This report systematically evaluates recent data (2018-2020) to identify the LC threshold in pregnancy in relation to safety considerations. Evidence from 11 reports suggests an optimal carbohydrate range of 47-70% EI supports normal fetal growth; higher than the conventionally recognized LC threshold. However, inadequate total maternal EI, which independently slows fetal growth was a frequent confounder across studies. Effects of a carbohydrate intake <175 g/d on maternal ketonemia and plasma triglyceride/free fatty acid concentrations remain unclear. A recent randomized controlled trial (RCT) suggests a higher risk for micronutrient deficiency with carbohydrate intake ≤165 g/d in GDM. Well-controlled prospective RCTs comparing LC (<165 g/d) and higher carbohydrate energy-balanced diets in pregnant women are clearly overdue.

TIMER: A Clinical Study of Energy Restriction in Women with Gestational Diabetes Mellitus

Medical nutrition therapy is an integral part of gestational diabetes mellitus (GDM) management; however, the prescription of optimal energy intake is often a difficult task due to the limited available evidence. The present pilot, feasibility, parallel, open-label and non-randomized study aimed to evaluate the effect of a very low energy diet (VLED, 1600 kcal/day), or a low energy diet (LED, 1800 kcal/day), with or without personalized exercise sessions, among women with GDM in singleton pregnancies. A total of 43 women were allocated to one of four interventions at GDM diagnosis: (1) VLED (n = 15), (2) VLED + exercise (n = 4), (3) LED (n = 16) or (4) LED + exercise (n = 8). Primary outcomes were gestational weight gain (GWG), infant birth weight, complications at delivery and a composite outcomes score. Secondary outcomes included type of delivery, prematurity, small- for-gestational-age (SGA) or large-for-gestational-age (LGA) infants, macrosomia, Apgar score, insulin use, depression, respiratory quotient (RQ), resting metabolic rate (RMR) and middle-upper arm circumference (MUAC). GWG differed between intervention groups (LED median: 12.0 kg; VLED: 5.9 kg). No differences were noted in the type of delivery, infant birth weight, composite score, prevalence of prematurity, depression, RQ, Apgar score, MUAC, or insulin use among the four groups. Regarding components of the composite score, most infants (88.4%) were appropriate-for-gestational age (AGA) and born at a gestational age of 37-42 weeks (95.3%). With respect to the mothers, 9.3% experienced complications at delivery, with the majority being allocated at the VLED + exercise arm (p < 0.03). The composite score was low (range 0-2.5) for all mother-infant pairs, indicating a "risk-free" pregnancy outcome. The results indicate that adherence to a LED or VLED induces similar maternal, infant and obstetrics outcomes.

The Role of Lifestyle Intervention in the Prevention and Treatment of Gestational Diabetes

Obesity during pregnancy is associated with the development of adverse outcomes, including gestational diabetes mellitus (GDM). GDM is highly associated with obesity and independently increases the risk of both complications during pregnancy and future impaired glycemic control and risk factors for cardiovascular disease for both the mother and child. Despite extensive research evaluating the effectiveness of lifestyle interventions incorporating diet and/or exercise, there remains a lack of definitive consensus on their overall efficacy alone or in combination for both the prevention and treatment of GDM. Combination of diet and physical activity/exercise interventions for GDM prevention demonstrates limited success, whereas exercise-only interventions report of risk reductions ranging from 3 to 49%. Similarly, combination therapy of diet and exercise is the first-line treatment of GDM, with positive effects on maternal weight gain and the prevalence of infants born large-for-gestational age. Yet, there is inconclusive evidence on the effects of diet or exercise as standalone therapies for GDM treatment. In clinical care, women with GDM should be treated with a multidisciplinary approach, starting with lifestyle modification and escalating to pharmacotherapy if needed. Several key knowledge gaps remain, including how lifestyle interventions can be optimized during pregnancy, and whether intervention during preconception is effective for preventing the rising prevalence of GDM.

Gestational Diabetes Mellitus Treatment Schemes Modify Maternal Plasma Cholesterol Levels Dependent to Women´s Weight: Possible Impact on Feto-Placental Vascular Function

: Gestational diabetes mellitus (GDM) associates with fetal endothelial dysfunction (ED), which occurs independently of adequate glycemic control. Scarce information exists about the impact of different GDM therapeutic schemes on maternal dyslipidemia and obesity and their contribution to the development of fetal-ED. The aim of this study was to evaluate the effect of GDM-treatments on lipid levels in nonobese (N) and obese (O) pregnant women and the effect of maternal cholesterol levels in GDM-associated ED in the umbilical vein (UV). O-GDM women treated with diet showed decreased total cholesterol (TC) and low-density lipoproteins (LDL) levels with respect to N-GDM ones. Moreover, O-GDM women treated with diet in addition to insulin showed higher TC and LDL levels than N-GDM women. The maximum relaxation to calcitonin gene-related peptide of the UV rings was lower in the N-GDM group compared to the N one, and increased maternal levels of TC were associated with even lower dilation in the N-GDM group. We conclude that GDM-treatments modulate the TC and LDL levels depending on maternal weight. Additionally, increased TC levels worsen the GDM-associated ED of UV rings. This study suggests that it could be relevant to consider a specific GDM-treatment according to weight in order to prevent fetal-ED, as well as to consider the possible effects of maternal lipids during pregnancy.

Evidenced-Based Nutrition for Gestational Diabetes Mellitus

PURPOSE OF REVIEW

To review the latest evidence for dietary interventions for treatment of gestational diabetes (GDM).

RECENT FINDINGS

High-quality systematic reviews demonstrate no major advantages between the low-carbohydrate or calorie-restricted diets. However, the low glycemic index (GI) diet, characterized by intake of high-quality, complex carbohydrates, demonstrated lower insulin use and reduced risk of macrosomia in multiple reviews. Recent evidence suggests the Mediterranean diet is safe in pregnancy, though trials are needed to determine its efficacy over conventional dietary advice. Currently, there are insufficient data to support the safety of the ketogenic diet for the treatment of GDM. The low GI diet may improve maternal and neonatal outcomes in GDM. The liberalized carbohydrate intake is less restrictive, culturally adaptable, and may improve long-term maternal adherence. Further research is needed to establish the optimal, most sustainable, and most acceptable medical nutrition therapy for management of women with GDM.

Improving pregnancy outcomes in women with diabetes mellitus: modern management

Women with pre-existing (type 1 or type 2) diabetes mellitus are at increased risk of pregnancy complications, such as congenital malformations, preeclampsia and preterm delivery, compared with women who do not have diabetes mellitus. Approximately half of pregnancies in women with pre-existing diabetes mellitus are complicated by fetal overgrowth, which results in infants who are overweight at birth and at risk of birth trauma and, later in life, the metabolic syndrome, cardiovascular disease and type 2 diabetes mellitus. Strict glycaemic control with appropriate diet, use of insulin and, if necessary, antihypertensive treatment is the cornerstone of diabetes mellitus management to prevent pregnancy complications. New technology for managing diabetes mellitus is evolving and is changing the management of these conditions in pregnancy. For instance, in Europe, most women with pre-existing diabetes mellitus are treated with insulin analogues before and during pregnancy. Furthermore, many women are on insulin pumps during pregnancy, and the use of continuous glucose monitoring is becoming more frequent. In addition, smartphone application technology is a promising educational tool for pregnant women with diabetes mellitus and their caregivers. This Review covers how modern diabetes mellitus management with appropriate diet, insulin and antihypertensive treatment in patients with pre-existing diabetes mellitus can contribute to reducing the risk of pregnancy complications such as congenital malformations, fetal overgrowth, preeclampsia and preterm delivery.

Lower daily carbohydrate consumption than recommended by the Institute of Medicine is common among women with type 2 diabetes in early pregnancy in Denmark

AIMS

To secure adequate carbohydrate supply in pregnancy, the Institute of Medicine (IOM) recommends a minimum amount of carbohydrates of 175 g daily. Currently a low carbohydrate diet is a popular health trend in the general population and this might also be common among overweight and obese pregnant women with type 2 diabetes (T2D). Thus, we explored carbohydrate consumption among pregnant women with T2D including women with type 1 diabetes (T1D) for comparison.

METHODS

A retrospective cohort study of consecutive women with T2D (N = 96) and T1D (N = 108), where dietary records were collected at the first antenatal visit.

RESULTS

Among women with T2D and T1D, bodyweight at the first visit was 90.8 ± 22 (mean ± SD) and 75.5 ± 15 kg (P < 0.001) while HbA1c was 6.6 ± 1.2% (49 ± 13 mmol/mol) and 6.6 ± 0.8% (48 ± 8 mmol/mol), P = 0.8, respectively. The average daily carbohydrate consumption from the major carbohydrate sources was similar in the two groups (159 ± 56 and 167 ± 48 g, P = 0.3), as was the level of total daily physical activity (median (interquartile range)): 215 (174-289) and 210 (178-267) metabolic equivalent of task-hour/week (P = 0.9). A high proportion of women with T2D and T1D (52% and 40%, P = 0.08) consumed fewer carbohydrates than recommended by the IOM. The prevalence of ketonuria (≥4 mmol/L) was 1% in both groups.

CONCLUSIONS

In early pregnancy, a lower daily carbohydrate consumption than recommended by the IOM was common among women with T2D. The results were quite similar to women with T1D, despite a markedly higher bodyweight in women with T2D. Reassuringly, ketonuria was rare in both groups.

Gestational diabetes mellitus: Multi-disciplinary treatment approaches

Gestational diabetes mellitus (GDM) is the most common metabolic disease of pregnancy, associated with several perinatal complications. Adequate glycemic control has been proved to decrease risk of GDM-related complications. Several studies have shown the beneficial effect of exercise and medical nutrition treatment on glycemic and weight control in GDM-affected women. Moreover, pharmacological agents, such as insulin and specific oral anti-diabetic agents can be prescribed safely during pregnancy, decreasing maternal blood glucose and, thus, perinatal adverse outcomes. Multi-disciplinary treatment approaches that include both lifestyle modifications (medical nutritional therapy and daily physical exercise) and pharmacological treatment, in cases of failure of the former, constitute the most effective approach. Insulin is the gold standard pharmacological agent for GDM treatment. Metformin and glyburide are two oral anti-diabetic agents that could serve as alternative, although not equal in terms of effectiveness and safety, treatment for GDM. As studies on short-term safety of metformin are reassuring, in some countries it is considered as first-line treatment for GDM management. More studies are needed to investigate the long-term effects on offspring. As safety issues have been raised on the use of glyburide during pregnancy, it must be used only when benefits surpass possible risks.

Different types of dietary advice for women with gestational diabetes mellitus

BACKGROUND

Dietary advice is the main strategy for managing gestational diabetes mellitus (GDM). It remains unclear what type of advice is best.

OBJECTIVES

To assess the effects of different types of dietary advice for women with GDM for improving health outcomes for women and babies.

SEARCH METHODS

We searched Cochrane Pregnancy and Childbirth's Trials Register (8 March 2016), PSANZ's Trials Registry (22 March 2016) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials comparing the effects of different types of dietary advice for women with GDM.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed study eligibility, risk of bias, and extracted data. Evidence quality for two comparisons was assessed using GRADE, for primary outcomes for the mother: hypertensive disorders of pregnancy; caesarean section; type 2 diabetes mellitus; and child: large-for-gestational age; perinatal mortality; neonatal mortality or morbidity composite; neurosensory disability; secondary outcomes for the mother: induction of labour; perineal trauma; postnatal depression; postnatal weight retention or return to pre-pregnancy weight; and child: hypoglycaemia; childhood/adulthood adiposity; childhood/adulthood type 2 diabetes mellitus.

MAIN RESULTS

In this update, we included 19 trials randomising 1398 women with GDM, at an overall unclear to moderate risk of bias (10 comparisons). For outcomes assessed using GRADE, downgrading was based on study limitations, imprecision and inconsistency. Where no findings are reported below for primary outcomes or pre-specified GRADE outcomes, no data were provided by included trials. Primary outcomes Low-moderate glycaemic index (GI) versus moderate-high GI diet (four trials): no clear differences observed for: large-for-gestational age (risk ratio (RR) 0.71, 95% confidence interval (CI) 0.22 to 2.34; two trials, 89 infants; low-quality evidence); severe hypertension or pre-eclampsia (RR 1.02, 95% CI 0.07 to 15.86; one trial, 95 women; very low-quality evidence); eclampsia (RR 0.34, 95% CI 0.01 to 8.14; one trial, 83 women; very low-quality evidence) or caesarean section (RR 0.66, 95% CI 0.29 to 1.47; one trial, 63 women; low-quality evidence). Energy-restricted versus no energy-restricted diet (three trials): no clear differences seen for: large-for-gestational age (RR 1.17, 95% CI 0.65 to 2.12; one trial, 123 infants; low-quality evidence); perinatal mortality (no events; two trials, 423 infants; low-quality evidence); pre-eclampsia (RR 1.00, 95% CI 0.51 to 1.97; one trial, 117 women; low-quality evidence); or caesarean section (RR 1.12, 95% CI 0.80 to 1.56; two trials, 420 women; low-quality evidence). DASH (Dietary Approaches to Stop Hypertension) diet versus control diet (three trials): no clear differences observed for: pre-eclampsia (RR 1.00, 95% CI 0.31 to 3.26; three trials, 136 women); however there were fewer caesarean sections in the DASH diet group (RR 0.53, 95% CI 0.37 to 0.76; two trials, 86 women). Low-carbohydrate versus high-carbohydrate diet (two trials): no clear differences seen for: large-for-gestational age (RR 0.51, 95% CI 0.13 to 1.95; one trial, 149 infants); perinatal mortality (RR 3.00, 95% CI 0.12 to 72.49; one trial, 150 infants); maternal hypertension (RR 0.40, 95% CI 0.13 to 1.22; one trial, 150 women); or caesarean section (RR 1.29, 95% CI 0.84 to 1.99; two trials, 179 women). High unsaturated fat versus low unsaturated fat diet (two trials): no clear differences observed for: large-for-gestational age (RR 0.54, 95% CI 0.21 to 1.37; one trial, 27 infants); pre-eclampsia (no cases; one trial, 27 women); hypertension in pregnancy (RR 0.54, 95% CI 0.06 to 5.26; one trial, 27 women); caesarean section (RR 1.08, 95% CI 0.07 to 15.50; one trial, 27 women); diabetes at one to two weeks (RR 2.00, 95% CI 0.45 to 8.94; one trial, 24 women) or four to 13 months postpartum (RR 1.00, 95% CI 0.10 to 9.61; one trial, six women). Low-GI versus high-fibre moderate-GI diet (one trial): no clear differences seen for: large-for-gestational age (RR 2.87, 95% CI 0.61 to 13.50; 92 infants); caesarean section (RR 1.91, 95% CI 0.91 to 4.03; 92 women); or type 2 diabetes at three months postpartum (RR 0.76, 95% CI 0.11 to 5.01; 58 women). Diet recommendation plus diet-related behavioural advice versus diet recommendation only (one trial): no clear differences observed for: large-for-gestational age (RR 0.73, 95% CI 0.25 to 2.14; 99 infants); or caesarean section (RR 0.78, 95% CI 0.38 to 1.62; 99 women). Soy protein-enriched versus no soy protein diet (one trial): no clear differences seen for: pre-eclampsia (RR 2.00, 95% CI 0.19 to 21.03; 68 women); or caesarean section (RR 1.00, 95% CI 0.57 to 1.77; 68 women). High-fibre versus standard-fibre diet (one trial): no primary outcomes reported. Ethnic-specific versus standard healthy diet (one trial): no clear differences observed for: large-for-gestational age (RR 0.14, 95% CI 0.01 to 2.45; 20 infants); neonatal composite adverse outcome (no events; 20 infants); gestational hypertension (RR 0.33, 95% CI 0.02 to 7.32; 20 women); or caesarean birth (RR 1.20, 95% CI 0.54 to 2.67; 20 women). Secondary outcomes For secondary outcomes assessed using GRADE no differences were observed: between a low-moderate and moderate-high GI diet for induction of labour (RR 0.88, 95% CI 0.33 to 2.34; one trial, 63 women; low-quality evidence); or an energy-restricted and no energy-restricted diet for induction of labour (RR 1.02, 95% CI 0.68 to 1.53; one trial, 114 women, low-quality evidence) and neonatal hypoglycaemia (average RR 1.06, 95% CI 0.48 to 2.32; two trials, 408 infants; very low-quality evidence).Few other clear differences were observed for reported outcomes. Longer-term health outcomes and health services use and costs were largely not reported.

AUTHORS' CONCLUSIONS

Evidence from 19 trials assessing different types of dietary advice for women with GDM suggests no clear differences for primary outcomes and secondary outcomes assessed using GRADE, except for a possible reduction in caesarean section for women receiving a DASH diet compared with a control diet. Few differences were observed for secondary outcomes.Current evidence is limited by the small number of trials in each comparison, small sample sizes, and variable methodological quality. More evidence is needed to assess the effects of different types of dietary advice for women with GDM. Future trials should be adequately powered to evaluate short- and long-term outcomes.

Macronutrient Composition or Social Determinants? Impact on Infant Outcomes With Gestational Diabetes Mellitus

The purpose of this study was to examine, through a randomized, controlled trial, the effects of a maternal carbohydrate-restricted diet on maternal and infant outcomes in gestational diabetes mellitus (GDM). Women diagnosed with GDM were randomly allocated into one of two groups: an intervention group that was placed on a lower-carbohydrate diet (35-40% of total calories) or a control group that was placed on the usual pregnancy diet (50-55% carbohydrate). A convenience sample of participants diagnosed with GDM (ages 18-45 years) was recruited from two different sites: one urban and low-income and the other suburban and more affluent. Individual face-to-face diet instruction occurred with certified diabetes educators at both sites. Participants tested their blood glucose four times daily. Specific socioeconomic status indicators included enrollment in the Supplemental Nutrition Program for Women, Infants and Children or Medicaid-funded health insurance, as well as cross-sectional census data. All analyses were based on an intention to treat. Although there were no differences found between the lower-carbohydrate and usual-care diets in terms of blood glucose or maternal-infant outcomes, there were significant differences noted between the two sites. There was a lower mean postprandial blood glucose (100.59 ± 7.3 mg/dL) at the suburban site compared to the urban site (116.3 ± 15 mg/dL) (P <0.01), even though there was no difference in carbohydrate intake. There were increased amounts of protein and fat consumed at the suburban site (P <0.01), as well as lower infant complications (P <0.01). Further research is needed to determine whether these disparities in outcomes were the result of macronutrient proportions or environmental conditions.

Role of Medical Nutrition Therapy in the Management of Gestational Diabetes Mellitus

Medical nutrition therapy (MNT) plays an important role in the management of gestational diabetes mellitus (GDM), and accordingly, it has a significant impact on women and newborns. The primary objective of MNT is to ensure adequate pregnancy weight gain and fetus growth while maintaining euglycemia and avoiding ketones. However, the optimal diet (energy content, macronutrient distribution, its quality and amount, among others) remains an outstanding question. Overall, the nutritional requirements of GDM are similar for all pregnancies, but special attention is paid to carbohydrates. Despite the classical intervention of restricting carbohydrates, the latest evidence, although limited, seems to favor a low-glycemic index diet. There is general agreement in the literature about caloric restrictions in the case of being overweight or obese. Randomized controlled trials are necessary to investigate the optimal MNT for GDM; this knowledge could yield health benefits and cost savings.

Pandemic of Pregnant Obese Women: Is It Time to Re-Evaluate Antenatal Weight Loss?

The Obesity pandemic will afflict future generations without successful prevention, intervention and management. Attention to reducing obesity before, during and after pregnancy is essential for mothers and their offspring. Preconception weight loss is difficult given that many pregnancies are unplanned. Interventions aimed at limiting gestational weight gain have produced minimal maternal and infant outcomes. Therefore, increased research to develop evidence-based clinical practice is needed to adequately care for obese pregnant women especially during antenatal care. This review evaluates the current evidence of obesity interventions during pregnancy various including weight loss for safety and efficacy. Recommendations are provided with the end goal being a healthy pregnancy, optimal condition for breastfeeding and prevent the progression of obesity in future generations.

Gestational diabetes mellitus: challenges in diagnosis and management

Gestational diabetes mellitus (GDM) is a well-characterized disease affecting a significant population of pregnant women worldwide. It has been widely linked to undue weight gain associated with factors such as diet, obesity, family history, and ethnicity. Poorly controlled GDM results in maternal and fetal morbidity and mortality. Improved outcomes therefore rely on early diagnosis and tight glycaemic control. While straightforward protocols exist for screening and management of diabetes mellitus in the general population, management of GDM remains controversial with conflicting guidelines and treatment protocols. This review highlights the diagnostic and management options for GDM in light of recent advances in care.

Influence of a ketogenic diet, fish-oil, and calorie restriction on plasma metabolites and lipids in C57BL/6J mice

BACKGROUND

Diet therapies including calorie restriction, ketogenic diets, and fish-oil supplementation have been used to improve health and to treat a variety of neurological and non-neurological diseases.

METHODS

We investigated the effects of three diets on circulating plasma metabolites (glucose and β-hydroxybutyrate), hormones (insulin and adiponectin), and lipids over a 32-day period in C57BL/6J mice. The diets evaluated included a standard rodent diet (SD), a ketogenic diet (KD), and a standard rodent diet supplemented with fish-oil (FO). Each diet was administered in either unrestricted (UR) or restricted (R) amounts to reduce body weight by 20%.

RESULTS

The KD-UR increased body weight and glucose levels and promoted a hyperlipidemic profile, whereas the FO-UR decreased body weight and glucose levels and promoted a normolipidemic profile, compared to the SD-UR. When administered in restricted amounts, all three diets produced a similar plasma metabolite profile, which included decreased glucose levels and a normolipidemic profile. Linear regression analysis showed that circulating glucose most strongly predicted body weight and triglyceride levels, whereas calorie intake moderately predicted glucose levels and strongly predicted ketone body levels.

CONCLUSIONS

These results suggest that biomarkers of health can be improved when diets are consumed in restricted amounts, regardless of macronutrient composition.

Normalizing metabolism in diabetic pregnancy: is it time to target lipids?

Outcomes in pregnancies complicated by preexisting diabetes (type 1 and type 2) and gestational diabetes mellitus have improved, but there is still excess morbidity compared with normal pregnancy. Management strategies appropriately focus on maternal glycemia, which demonstrably improves pregnancy outcomes for mother and infant. However, we may be reaching the boundaries of obtainable glycemic control for many women. It has been acknowledged that maternal lipids are important in pregnancies complicated by diabetes. Elevated maternal lipids are associated with preeclampsia, preterm delivery, and large-for-gestational-age infants. Despite this understanding, assessment of management strategies targeting maternal lipids has been neglected to date. Consideration needs to be given to whether normalizing maternal lipids would further improve pregnancy outcomes. This review examines the dyslipidemia associated with pregnancy complicated by diabetes, reviews possible therapies, and considers whether it is time to start actively managing this aspect of maternal metabolism.

Diabetes and pregnancy: an endocrine society clinical practice guideline

OBJECTIVE

Our objective was to formulate a clinical practice guideline for the management of the pregnant woman with diabetes.

PARTICIPANTS

The Task Force was composed of a chair, selected by the Clinical Guidelines Subcommittee of The Endocrine Society, 5 additional experts, a methodologist, and a medical writer.

EVIDENCE

This evidence-based guideline was developed using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system to describe both the strength of recommendations and the quality of evidence.

CONSENSUS PROCESS

One group meeting, several conference calls, and innumerable e-mail communications enabled consensus for all recommendations save one with a majority decision being employed for this single exception.

CONCLUSIONS

Using an evidence-based approach, this Diabetes and Pregnancy Clinical Practice Guideline addresses important clinical issues in the contemporary management of women with type 1 or type 2 diabetes preconceptionally, during pregnancy, and in the postpartum setting and in the diagnosis and management of women with gestational diabetes during and after pregnancy.

Weight loss after diagnosis with gestational diabetes and birth weight among overweight and obese women

To determine if, among overweight or obese women with gestational diabetes (GDM), weight loss after GDM diagnosis is associated with lower infant birth weight within levels of overweight or obesity class. Overweight and obese women with singleton pregnancies managed for GDM at a large diabetes and pregnancy program located in Charlotte, NC between November 2000 and April 2010, were eligible for this retrospective cohort study. All were managed using a rigorous standardized clinical protocol. Clinical information including maternal pre-pregnancy body mass index, gestational weight gain, treatment, and medical and obstetric history was abstracted from medical records. The association of weight loss after GDM diagnosis and birth weight was analyzed using linear regression stratified by maternal pre-pregnancy overweight or obesity class (I, II/III). Of the 322 women in this study 19 % lost weight between diagnosis of GDM and delivery. After adjustment for maternal age, parity, race/ethnicity, gestational week at first hemoglobin A1c (A1C), A1C at diagnosis, weight gain prior to GDM, treatment with insulin or oral hypoglycemic agents, gestational age at delivery, and infant sex, weight loss was associated with 238.3 g lower mean infant birth weight among overweight women (95 % CI -393.72, -82.95 g), but was not associated with lower mean infant birth weight among obese class II/III women (95 % CI -275.61, 315.38 g). Weight loss, after diagnosis of GDM, is associated with lower infant birth weight among overweight women, but not among obese class II/III women.

Impact of restricted maternal weight gain on fetal growth and perinatal morbidity in obese women with type 2 diabetes

OBJECTIVE

Since January 2008, obese women with type 2 diabetes were advised to gain 0-5 kg during pregnancy. The aim with this study was to evaluate fetal growth and perinatal morbidity in relation to gestational weight gain in these women.

RESEARCH DESIGN AND METHODS

A retrospective cohort comprised the records of 58 singleton pregnancies in obese women (BMI ≥30 kg/m(2)) with type 2 diabetes giving birth between 2008 and 2011. Birth weight was evaluated by SD z score to adjust for gestational age and sex.

RESULTS

Seventeen women (29%) gained ≤5 kg, and the remaining 41 gained >5 kg. The median (range) gestational weight gains were 3.7 kg (-4.7 to 5 kg) and 12.1 kg (5.5-25.5 kg), respectively. Prepregnancy BMI was 33.5 kg/m(2) (30-53 kg/m(2)) vs. 36.8 kg/m(2) (30-48 kg/m(2)), P = 0.037, and median HbA1c was 6.7% at first visit in both groups and decreased to 5.7 and 6.0%, P = 0.620, in late pregnancy, respectively. Gestational weight gain ≤5 kg was associated with lower birth weight z score (P = 0.008), lower rates of large-for-gestational-age (LGA) infants (12 vs. 39%, P = 0.041), delivery closer to term (268 vs. 262 days, P = 0.039), and less perinatal morbidity (35 vs. 71%, P = 0.024) compared with pregnancies with maternal weight gain >5 kg.

CONCLUSIONS

In this pilot study in obese women with type 2 diabetes, maternal gestational weight gain ≤5 kg was associated with a more proportionate birth weight and less perinatal morbidity.

Different types of dietary advice for women with gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus (GDM) affects a significant number of women each year and is associated with a wide range of adverse outcomes for women and their babies. Dietary counselling is the main strategy in managing GDM, but it remains unclear which dietary therapy is best.

OBJECTIVES

To assess the effects of different types of dietary advice for women with GDM on pregnancy outcomes.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (17 May 2012) and the WOMBAT Perinatal Trials Registry (17 April 2012).

SELECTION CRITERIA

Randomised controlled trials (RCTs) and cluster-RCTs assessing the effects of different types of dietary advice for women with GDM on pregnancy outcomes.We intended to compare two or more forms of the same type of dietary advice against each other, i.e. standard dietary advice compared with individualised dietary advice, individual dietary education sessions compared with group dietary education sessions. We intended to compare different intensities of dietary intervention with each other, i.e. single dietary counselling session compared with multiple dietary counselling sessions.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed study eligibility, extracted data and assessed risk of bias of included studies. Data were checked for accuracy.

MAIN RESULTS

We included nine trials; 429 women (436 babies) provided outcome data. All nine included trials had small sample sizes with variation in levels of risk of bias. A total of 11 different types of dietary advice were assessed under six different comparisons, including:low-moderate glycaemic index (GI) food versus high-moderate GI food, low-GI diet versus high-fibre moderate-GI diet, energy-restricted diet versus no energy restriction diet, low-carbohydrate diet (≤ 45% daily total energy intake from carbohydrate) versus high-carbohydrate diet (≥ 50% daily total energy intake from carbohydrate), high-monounsaturated fat diet (at least 20% total energy from monounsaturated fat) versus high-carbohydrate diet (at least 50% total energy from carbohydrate), standard-fibre diet (American Diabetes Association (ADA) diet) (20 grams fibre/day) versus fibre-enriched diet (80 grams fibre/day).In the low-moderate GI food versus moderate-high GI food comparison, no significant differences were seen for macrosomia or large-for-gestational age (LGA), (two trials, 89 babies) (risk ratio (RR) 0.45, 95% confidence interval (CI) 0.10 to 2.08), (RR 0.95, 95% CI 0.27 to 3.36), respectively; or caesarean section (RR 0.66, 95% CI 0.29 to 1.47, one trial, 63 women).In the low-GI diet versus high-fibre moderate-GI diet comparison, no significant differences were seen for macrosomia or LGA (one trial, 92 babies) (RR 0.32, 95% CI 0.03 to 2.96), (RR 2.87, 95% CI 0.61 to 13.50), respectively; or caesarean section (RR 1.80, 95% CI 0.66 to 4.94, one trial, 88 women).In the energy-restricted versus unrestricted diet comparison, no significant differences were seen for macrosomia (RR 1.56, 95% CI 0.61 to 3.94, one trial, 122 babies); LGA (RR 1.17, 95% CI 0.65 to 2.12, one trial, 123 babies); or caesarean section (RR 1.18, 95% CI 0.74 to 1.89, one trial, 121 women).In the low- versus high-carbohydrate diet comparison, none of the 30 babies in a single trial were macrosomic; and no significant differences in caesarean section rates were seen (RR 1.40, 95% CI 0.57 to 3.43, one trial, 30 women).In the high-monounsaturated fat versus high-carbohydrate diet comparison, neither macrosomia or LGA (one trial 27 babies) (RR 0.65, 95% CI 0.91 to 2.18), (RR 0.54 95% CI 0.21 to 1.37), respectively showed significant differences. Women having a high-monounsaturated fat diet had a significantly higher body mass index (BMI) at birth (mean difference (MD) 3.90 kg/m², 95% CI 2.41 to 5.39, one trial, 27 women) and at six to nine months postpartum (MD 4.10 kg/m², 95% CI 2.34 to 5.86, one trial, 27 women) when compared with those having a high-carbohydrate diet. However, these findings were based on a single, small RCT with baseline imbalance in maternal BMI.Perinatal mortality was reported in only trial which recorded no fetal deaths in either the energy- restricted or unrestricted diet group.A single trial comparing ADA diet (20 grams gram fibre/day) with fibre-enriched fibre enriched diet (80 grams gram fibre/day) did not report any of our prespecified primary outcomes.Very limited data were reported on the prespecified outcomes for each of the six comparisons. Only one trial reported on early postnatal outcomes. No trial reported long-term health outcomes for women and their babies. No data were reported on health service cost or women's quality of life.

AUTHORS' CONCLUSIONS

Data for most comparisons were only available from single studies and they are too small for reliable conclusions about which types of dietary advice are the most suitable for women with GDM. Based on the current available evidence, we did not find any significant benefits of the diets investigated.Further larger trials with sufficient power to assess the effects of different diets for women with GDM on maternal and infant health outcomes are needed. Outcomes such as longer-term health outcomes for women and their babies, women's quality of life and health service cost should be included.

Gestational diabetes mellitus

BACKGROUND

Gestational diabetes mellitus, defined as diabetes diagnosed during pregnancy that is not clearly overt diabetes, is becoming more common as the epidemic of obesity and type 2 diabetes continues. Newly proposed diagnostic criteria will, if adopted universally, further increase the prevalence of this condition. Much controversy surrounds the diagnosis and management of gestational diabetes.

CONTENT

This review provides information regarding various approaches to the diagnosis of gestational diabetes and the recommendations of a number of professional organizations. The implications of gestational diabetes for both the mother and the offspring are described. Approaches to self-monitoring of blood glucose concentrations and treatment with diet, oral medications, and insulin injections are covered. Management of glucose metabolism during labor and the postpartum period are discussed, and an approach to determining the timing of delivery and the mode of delivery is outlined.

SUMMARY

This review provides an overview of current controversies as well as current recommendations for gestational diabetes care.

Low Glycemic Index Carbohydrates versus All Types of Carbohydrates for Treating Diabetes in Pregnancy: A Randomized Clinical Trial to Evaluate the Effect of Glycemic Control

Background. Due to the higher prevalence of obesity and diabetes mellitus (DM), more pregnant women complicated with diabetes are in need of clinical care. Purpose. Compare the effect of including only low glycemic index (GI) carbohydrates (CHO) against all types of CHO on maternal glycemic control and on the maternal and newborn's nutritional status of women with type 2 DM and gestational diabetes mellitus (GDM). Methods. Women (n = 107, ≤29 weeks of gestation) were randomly assigned to one of two nutrition intervention groups: moderate energy and CHO restriction (Group 1: all types of CHO, Group 2: low GI foods). Results. No baseline differences in clinical data were observed. Capillary glucose concentrations throughout pregnancy were similar between groups. Fewer women in Group 2 exceeded weight gain recommendations. Higher risk of prematurity was observed in women in Group 2. No differences in glycemic control were observed between women with type 2 DM and those with GDM. Conclusions. Inclusion of low GI CHO as part of a comprehensive nutrition intervention is equally effective in improving glycemic control as compared to all types of CHO. This strategy had a positive effect in preventing excessive maternal weight gain but increased the risk of prematurity.

Turning the tide: type 2 diabetes trends in offspring of mothers with gestational diabetes mellitus

In this review, the thesis is presented that maternal hyperglycemia produces an overnourished, fat fetus. If the fetus has a predisposition for type 2 diabetes, then the fat deposition in the fetus is predominantly in the fetal visceral cavity. Visceral fat deposition is the origin of insulin resistance. The fat fetus begins life with its pancreatic output of insulin compromised. Thus, the stage is set for developing type 2 diabetes in its lifetime. This review supports the hypothesis that normalization of maternal nutrition and fucose will decrease the risk of type 2 diabetes.

Approach to the patient with diabetes during pregnancy

The epidemics of obesity and type 2 diabetes mellitus (T2DM) globally are paralleling an increase in the number of women with T2DM becoming pregnant. Because T2DM is frequently undiagnosed before pregnancy, the risk of major malformations in the developing fetus is increased due to uncontrolled hyperglycemia. The lack of preconception care and the increase in complications of pregnancy due to the coexistence of obesity and T2DM are of concern from both an individual and a public health standpoint. Rapid achievement of normoglycemia with limited weight gain is critical to optimize maternal and fetal outcomes in all women with diabetes during pregnancy, regardless of the type of diabetes. This article will focus on T2DM preceding pregnancy due to its increasing prevalence and potentially dire fetal and maternal consequences. Euglycemia before, during, and after all pregnancies complicated by diabetes results in the best opportunity for optimal outcomes for mother and infant.

Prevention of gestational diabetes mellitus: a review of studies on weight management

Entering pregnancy with overweight, obesity or gaining excessive gestational weight could increase the risk of gestational diabetes mellitus (GDM), which is associated with negative consequences for both the mother and the offspring. The objective of this article was to review scientific evidence regarding the association between obesity and GDM, and how weight management through nutritional prevention strategies could prove successful in reducing the risk for GDM. Studies published between January 1975 and January 2009 on the relationship between GDM, pre-pregnancy body mass index (BMI), gestational weight gain and nutritional prevention strategies were included in this review. Results from these reports suggest that maternal obesity assessed by pre-pregnancy BMI is associated with an increased risk of GDM. They also show an association between gestational weight gain and increased risk for GDM. Higher dietary fat and lower carbohydrate intakes during pregnancy appear to be associated with a higher risk for GDM, independent of pre-pregnancy BMI. Some studies showed that restricting energy and carbohydrates could minimize gestational weight gain. However, a firm conclusion on the most effective nutritional intervention for the control of gestational weight gain and glycaemic responses could not be reached based on available studies. In light of the studies reviewed, we conclude that weight management through nutritional prevention strategies could be successful in reducing the risk of GDM. Further studies are required to identify the most effective diet composition to prevent GDM and excessive gestational weight gain.

A Medical Nutrition Therapy Program Improves Perinatal Outcomes in Mexican Pregnant Women With Gestational Diabetes and Type 2 Diabetes Mellitus

Diabetes in pregnancy is a major public health problem in Mexico. Nutrition therapy is an important component of treatment. Intensive nutrition intervention has not been implemented for Mexican pregnant women with diabetes. Its effect on different types of diabetes mellitus has not been studied.

Purpose

The authors assessed the effect of a medical nutrition therapy (MNT) program on perinatal complications in Mexico City.

Methods

Quasi-experimental design with a historical control. Women were assigned to a MNT program (n = 88) and were followed up with every 2 weeks until delivery (2004-2007). The control group (n = 86) was selected from medical charts (2001-2003) and the same inclusion criteria were used. In each group, 55% of women had type 2 diabetes mellitus and 45% had gestational diabetes. The MNT program included a moderate intake of carbohydrate (40%-45% of total energy) and reduction in energy intake, capillary glucose self-monitoring, and education. The control group received usual hospital routine care. Statistical analysis included descriptive statistics, chi-square, and multivariate logistic regression (OR, 95% CI) as indicated.

Results

Women in the MNT program had a lower risk of preeclampsia, fewer maternal hospitalization, and neonatal deaths in both types of diabetes. Low birth weight was less frequent only in women with gestational diabetes receiving MNT, while neonatal intensive care unit admissions were lower only in women with type 2 diabetes.

Conclusions

An intensive MNT program, including counseling, education, and capillary glucose self-monitoring, has a positive effect over preeclampsia, maternal hospitalization, and neonatal death in women with diabetes in pregnancy. MNT guidelines should be implemented in Mexican health care facilities treating diabetes in pregnancy.

Independent predictors of Cesarean delivery in women with diabetes

OBJECTIVES

To identify independent risk factors for Cesarean delivery in women with pregnancy complicated by diabetes.

METHODS

Retrospective analysis of pregnancies from 5735 diabetic women delivering liveborn infants. Maternal demographic, medical, obstetric historical factors and index pregnancy obstetric, glycemic and neonatal outcome parameters were evaluated for association with Cesarean delivery after a trial of labor. Individual risk factors were analyzed for association by chi2 and ANOVA. Independent predictors of Cesarean delivery and adjusted relative risk (RR) were identified by stepwise logistic regression.

RESULTS

Trial of labor was permitted in 90.8% and 59.4% of women without (n = 4643) and with prior Cesarean delivery (n = 1092) and was successful in 85.2% and 56.9%, respectively. Eleven independent predictors were found. Five were related to obstetric history and maternal age: prior Cesarean delivery (RR 5.34, 95% CI 3.94-7.25), no prior live birth (RR 3.17, 95% CI 1.98-5.07), no prior vaginal delivery (RR 2.28, 95% CI 1.50-3.44), prior stillbirth (RR 1.71, 95% CI 1.09-2.68%) and maternal age > or = 35 years (RR 1.53, 95% CI 1.20-1.93). Two were related to the severity of diabetes at entry to diabetes care: requiring insulin (RR 1.53, 95% CI 1.20-1.93) and highest fasting plasma glucose level (RR 1.04, 95% CI 1.01-1.07). Two were related to obstetric factors: pre-eclampsia/hypertension (RR 2.56, 95% CI 2.00-3.27) and labor induction (RR 3.32, 95% CI 2.70-4.10). The remaining two were birth weight (per 250 g, RR 1.12, 95% CI 1.09-1.17) and pre-delivery body mass index (RR, 1.03, 95% CI 1.00-1.05).

CONCLUSION

The majority of predictors were not modifiable, relating to obstetric history, maternal age and diabetes severity. Possible modifiable interventions to avoid/improve labor induction, and decrease birth weight and maternal weight gain might decrease risk of Cesarean delivery. Future studies must address these multiple predictors.

Gestational diabetes: pathogenesis and consequences to mother and offspring

Gestational diabetes mellitus (GDM) is defined as glucose intolerance with onset or first recognition during pregnancy. Data from Western countries suggest that the prevalence of GDM is increasing, being almost 10% of pregnancies and probably reflecting the global obesity epidemic. The majority of women with GDM seem to have beta-cell dysfunction that appears on a background of chronic insulin resistance already present before pregnancy. In less than 10% of GDM patients, defects of beta-cell function can be due to autoimmune destruction of pancreatic beta-cells, as in type 1 diabetes, or caused by monogenic mutations, as in several MODY subtypes. Diagnostic criteria for GDM vary worldwide and there are no clear-cut plasma glucose cut-off values for identifying women at a higher risk of developing macrosomia or other fetal complications. Because the oral glucose tolerance test (OGTT) is restricted to high risk individuals, 40% of GDM cases are left undiagnosed. Therefore, in high risk populations almost universal screening is recommended; only women considered to have very low risk do not need screening. Diet and exercise are the key elements in the treatment of GDM. If necessary, either insulin, certain oral hypoglycemic agents or combinations can be used to achieve normoglycemia. After delivery, women with GDM and their offspring have an increased risk for developing the metabolic syndrome and type 2 diabetes. Thus, pregnancy may act as a "stress test", revealing a woman's predisposition to T2D and providing opportunities for focused prevention of important chronic diseases.

Alternate day calorie restriction improves clinical findings and reduces markers of oxidative stress and inflammation in overweight adults with moderate asthma

Asthma is an increasingly common disorder responsible for considerable morbidity and mortality. Although obesity is a risk factor for asthma and weight loss can improve symptoms, many patients do not adhere to low calorie diets and the impact of dietary restriction on the disease process is unknown. A study was designed to determine if overweight asthma patients would adhere to an alternate day calorie restriction (ADCR) dietary regimen, and to establish the effects of the diet on their symptoms, pulmonary function and markers of oxidative stress, and inflammation. Ten subjects with BMI>30 were maintained for 8 weeks on a dietary regimen in which they ate ad libitum every other day, while consuming less than 20% of their normal calorie intake on the intervening days. At baseline, and at designated time points during the 8-week study, asthma control, symptoms, and Quality of Life questionnaires (ACQ, ASUI, mini-AQLQ) were assessed and blood was collected for analyses of markers of general health, oxidative stress, and inflammation. Peak expiratory flow (PEF) was measured daily on awakening. Pre- and postbronchodilator spirometry was obtained at baseline and 8 weeks. Nine of the subjects adhered to the diet and lost an average of 8% of their initial weight during the study. Their asthma-related symptoms, control, and QOL improved significantly, and PEF increased significantly, within 2 weeks of diet initiation; these changes persisted for the duration of the study. Spirometry was unaffected by ADCR. Levels of serum beta-hydroxybutyrate were increased and levels of leptin were decreased on CR days, indicating a shift in energy metabolism toward utilization of fatty acids and confirming compliance with the diet. The improved clinical findings were associated with decreased levels of serum cholesterol and triglycerides, striking reductions in markers of oxidative stress (8-isoprostane, nitrotyrosine, protein carbonyls, and 4-hydroxynonenal adducts), and increased levels of the antioxidant uric acid. Indicators of inflammation, including serum tumor necrosis factor-alpha and brain-derived neurotrophic factor, were also significantly decreased by ADCR. Compliance with the ADCR diet was high, symptoms and pulmonary function improved, and oxidative stress and inflammation declined in response to the dietary intervention. These findings demonstrate rapid and sustained beneficial effects of ADCR on the underlying disease process in subjects with asthma, suggesting a novel approach for therapeutic intervention in this disorder.

Rationale for prevention and treatment of glucose-mediated macrosomia: a protocol for gestational diabetes

OBJECTIVE

To formulate a rationale for preventing and treating hyperglycemia during pregnancy and the concomitant risk of macrosomia.

METHODS

We reviewed pertinent studies in the literature and personal experience with patients who had gestational diabetes. In addition, dietary and exercise interventions in the management of such patients were assessed.

RESULTS

During pregnancy, sequential hormonal increases occur to provide glucose substrate to the fetus. When a pregnant woman has a limited insulin secretory capacity and cannot produce enough insulin to compensate for the effect of diabetogenic hormones, gestational diabetes occurs (usually during the second trimester). Maternal hyperglycemia reportedly increases fetal secretion of insulin, and fetal hyperinsulinemia may predispose the fetus to macrosomia. Thus, metabolic abnormalities associated with diabetes during pregnancy result in long-term effects on the offspring, including insulin resistance, obesity, and diabetes, which in turn may contribute to transmission of risk for development of the same problems in subsequent generations. Insulin therapy, dietary measures, and exercise have helped to achieve euglycemia in patients with gestational diabetes.

CONCLUSION

Universal screening for gestational diabetes is optimally performed at 26 weeks of gestation. Treatment of diagnosed cases, by insulin, diet, and exercise regimens, will decrease the occurrence of glucose-related macrosomia, improve the outcome of the pregnancy, and reduce the risks for obesity, hypertension, and diabetes in future progeny.

Nutrition and pregnancy: the link between dietary intake and diabetes

Pregnancy is a time when serial metabolic changes in the mother are carefully regulated to provide optimum substrate to both mother and fetus. Subtle perturbations in maternal metabolism can have implications not only for the index pregnancy, but also for future generations. The literature provides evidence that maternal nutrition plays a major role in the destiny of the offspring. Both maternal malnutrition and overnutrition are associated with subsequent diabetes in the offspring. Pregnancy represents a window of opportunity for health care providers to change dietary patterns toward habits that will be healthier for the individual now, as well as impacting on the future. The challenge for clinicians is to provide nutritional information based on scientific evidence that facilitates the normalization of fetal nutrition, and thus minimize the risk that the child will develop diabetes.

Achieving Euglycaemia in Women with Gestational Diabetes Mellitus

Gestational diabetes mellitus is one of the major medical complications of pregnancy. Untreated, the mother and the unborn child may experience morbidity and fetal death may even occur. It is important to diagnose and treat all hyperglycaemia appearing during pregnancy. Ideally, a screening and diagnostic test that identified all women at risk for hyperglycaemia-associated complications would be employed in all pregnant women. Unfortunately, there is no such test available currently. The best alternative is to administer an oral glucose challenge test to all pregnant women and then apply the best strategies for interpretation. This article discusses the limitations of our present diagnostic tools and suggests an option for the clinician until the definitive test has been elucidated. In addition, this article outlines one dietary and management strategy that has been associated with an outcome of pregnancy that is similar to the outcome of pregnancies in healthy women. This strategy includes starting with a "euglycaemic" diet (comprising < 40% carbohydrates and > or =40% fat), which can then be individualised according to the patient's glucose levels. Appropriate exercise, such as arm ergometer training, may enhance the benefits of diet control. For patients who require insulin, if the fasting glucose level is >90 mg/dL or 5 mmol/L (whole blood capillary) then NPH insulin (insulin suspension isophane) should be given before bed, beginning with dosages of 0.2 U/kg/day. If the postprandial glucose level is elevated, pre-meal rapid-acting insulin should be prescribed, beginning with a dose of 1U per 10g of carbohydrates in the meal. If both the fasting and postprandial glucose levels are elevated, or if a woman's postprandial glucose levels can only be blunted if starvation ketosis occurs, a four-injections-per-day regimen should be prescribed. The latter can be based on combinations of NPH insulin and regular human insulin, timed to provide basal and meal-related insulin boluses. The total daily insulin dose for the four-injection regimen should be adjusted according to pregnant bodyweight and gestational week (0.7-1 U/kg/day); doses may need to be increased for the morbidly obese or when there is twin gestation. There is now some evidence that insulin lispro, other insulin analogues and oral antihyperglycaemic drugs may be beneficial in gestational diabetes, and more data on these agents are awaited with interest.

Development of early-onset type 2 diabetes in the young: implications for child bearing

The prevalence of type 2 diabetes mellitus is increasing in children and adolescents worldwide, particularly among minority youth. This has led to an increase in the number of pregnancies complicated by type 2 diabetes, which has now exceeded pregnancies complicated by type 1 diabetes. Although the data are somewhat limited, those studies that are available seem to indicate that the rate of adverse maternal and fetal outcomes is at least as great, if not greater, for type 2 as for type 1 diabetes. It has been postulated that some of the excess risk is due to the fact that women with type 2 diabetes are older, heavier, less likely to seek early prenatal care, and are generally in less satisfactory glycemic control. This article reviews the existing data on pregnancies complicated by type 2 diabetes and the implications for management and prevention.

The principles of dietary management of gestational diabetes: reflection on current evidence

BACKGROUND

Gestational diabetes (GDM) is the commonest metabolic disorder of pregnancy. Most women with GDM are treated with nutritional management alone. There are conflicting guidelines surrounding its dietary management and this has resulted in a lack of conformity to the dietary advice currently prescribed. There is also conflicting opinions to the effectiveness of dietary management of GDM on pregnancy outcomes. The aim of this review was to examine the scientific evidence for the optimal nutritional management of GDM.

METHODS

A Medline search of all English papers published between 1995 and 2001 that cross-referenced GDM with diet was under taken. Because of the poor quality of many of these papers, literature prior to 1995 known to the authors and considered relevant to the review were also included.

RESULTS

The evidence base in this area is of poor quality. One systematic review based on randomized control trials failed to show any benefit from dietary intervention in GDM. However, that review did not include informative clinical and observational studies that are not classified as randomized controlled trials. Overall current evidence points to the effectiveness of dietary advice as a means of improving maternal hyperglycaemia and reducing the risk of accelerated foetal growth. The evidence surrounding energy restriction, carbohydrate and fat manipulation in GDM remains controversial.

CONCLUSIONS

Current but limited evidence supports dietary alterations to reduce rates of accelerated foetal growth. There is a clear need for good quality randomized control trials in this area.

Caloric restriction inhibits seizure susceptibility in epileptic EL mice by reducing blood glucose

PURPOSE

Caloric restriction (CR) involves underfeeding and has long been recognized as a dietary therapy that improves health and increases longevity. In contrast to severe fasting or starvation, CR reduces total food intake without causing nutritional deficiencies. Although fasting has been recognized as an effective antiseizure therapy since the time of the ancient Greeks, the mechanism by which fasting inhibits seizures remains obscure. The influence of CR on seizure susceptibility was investigated at both juvenile (30 days) and adult (70 days) ages in the EL mouse, a genetic model of multifactorial idiopathic epilepsy.

METHODS

The juvenile EL mice were separated into two groups and fed standard lab chow either ad libitum (control, n=18) or with a 15% CR diet (treated, n=17). The adult EL mice were separated into three groups; control (n=15), 15% CR (n=6), and 30% CR (n=3). Body weights, seizure susceptibility, and the levels of blood glucose and ketones (beta-hydroxybutyrate) were measured over a 10-week treatment period. Simple linear regression and multiple logistic regression were used to analyze the relations among seizures, glucose, and ketones.

RESULTS

CR delayed the onset and reduced the incidence of seizures at both juvenile and adult ages and was devoid of adverse side effects. Furthermore, mild CR (15%) had a greater antiepileptogenic effect than the well-established high-fat ketogenic diet in the juvenile mice. The CR-induced changes in blood glucose levels were predictive of both blood ketone levels and seizure susceptibility.

CONCLUSIONS

We propose that CR may reduce seizure susceptibility in EL mice by reducing brain glycolytic energy. Our preclinical findings suggest that CR may be an effective antiseizure dietary therapy for human seizure disorders.

Eating disorders, fertility, and pregnancy: relationships and complications

Women are becoming heavier with each generation although the ideal female image emphasizes slimness. This focus results in the development of eating disorders in a significant number of women. The most common eating disorders are anorexia nervosa and bulimia nervosa. Eating disorder behaviors during pregnancy are associated with complications such as preterm delivery, low birthweight, intrauterine growth restriction, Caesarean birth, and low Apgar scores. Increasing the understanding of eating disorders assists health care professionals to accurately assess and intervene to improve a woman's nutritional status, monitor eating behaviors that may negatively affect a woman's health and fertility, and promote positive outcomes during pregnancy.