Aims/Introduction: Efficacy of long‐term low‐carbohydrate diets (LCD) to improve glycemic management for type 2 diabetes remains controversial. Thus, we investigated the association between long‐term LCD and glycemic control in individuals with type 2 diabetes.Materials and Methods: We searched PubMed, Embase and the Cochrane Database for articles published up to June 2023, and included randomized controlled trials conducted on LCD interventions for >12 months in adults with type 2 diabetes. Primary outcome was the difference in glycated hemoglobin between long‐term LCD and control groups. Additionally, we evaluated the differences in changes in systolic and diastolic blood pressure, low‐density lipoprotein cholesterol, high‐density lipoprotein cholesterol, triglyceride, and weight between long‐term LCD and control groups.Results: Six studies were identified and met the inclusion criteria. This study did not show significant differences in changes in glycated hemoglobin between long‐term LCD and control diets (standardized mean difference −0.11, 95% confidence interval −0.33 to 0.11, P = 0.32). As with glycemic control, there were no significant differences in the changes in weight loss, blood pressure, and low‐density lipoprotein cholesterol between long‐term LCD and control diets. However, long‐term LCD were associated with greater elevation in high‐density lipoprotein cholesterol (standardized mean difference 0.22, 95% confidence interval 0.04–0.41; P = 0.02) and decrease in triglyceride (standardized mean difference −0.19; 95% confidence interval −0.37 to 0.02; P = 0.03) than that in control diets.Conclusions: Our findings suggest efficacy of long‐term LCD in treating dyslipidemia in individuals with type 2 diabetes, but do not recommend long‐term LCD for glycemic control in the individuals.

Context Branched-chain amino acids (BCAA) are substrates for protein synthesis. Although their intake may contribute to an increase in skeletal muscle mass, elevated serum BCAA levels have been reported to be associated with insulin resistance, potentially resulting in decreased skeletal muscle mass. Objective This study aimed to explore the association between elevated serum BCAA levels and longitudinal skeletal muscle loss. Design and Setting A cohort analysis was conducted, in which serum amino acids were analyzed in healthy individuals who underwent a medical health checkup at Kameoka Municipal Hospital (HOZUGAWA study), Japan. Patients Seventy-one participants (37 men and 34 women) underwent follow-up checkups after the baseline visit. The follow-up duration was 1.2 ± .4 years. Main Outcome Measures The relationship between fasting baseline serum BCAA levels and lifestyle factors, body composition, blood test results, dietary history, and changes in skeletal muscle mass was evaluated. Results In both men and women, serum BCAA levels were positively correlated with body weight, body mass index, skeletal muscle mass index (SMI), and serum triglycerides but inversely correlated with serum high-density lipoprotein cholesterol. In men, fasting serum BCAA levels were inversely associated with the rate of change in SMI (adjusted β = −.529, P = .006), and elevated BCAA levels were independently associated with a longitudinal decrease in skeletal muscle mass (odds ratio: 1.740; 95% confidence interval: 1.023-2.960 per 50 nmol/mL serum BCAAs increase). Conclusion Increased circulating BCAAs could be an indicator of skeletal muscle loss in men.

Low phase angle (PhA), as determined via bioelectrical impedance analysis, reflects unhealthy aging and mortality. In this study, we assessed whether nutritional status, including serum nutritional markers and dietary habits, is related to PhA in older individuals. We recruited 212 participants (aged ≥ 65 years) who underwent medical health checkups. PhA was measured using a multi-frequency impedance body composition analyzer. Habitual food and nutrient intake was evaluated using a brief, self-administered diet history questionnaire. Low PhA values were defined as ≤4.95 in males and ≤4.35 in females. Males with low PhA had poor exercise habits (p = 0.0429) and a lower body mass index (p = 0.0024). PhA was significantly correlated with serum cholinesterase levels, a nutritional status marker (r = 0.3313, p = 0.0004 in males; r = 0.3221, p = 0.0070 in females). The low-PhA group had significantly lower total energy and carbohydrate intake per ideal body weight (IBW) than the high-PhA group in males (total energy intake:30.2 ± 9.8 and 34.5 ± 9.3 kcal/kg/day, p = 0.0307; carbohydrate intake:15.2 ± 4.9 and 18.0 ± 5.8 kcal/kg/day, p = 0.0157). Total energy intake per IBW (adjusted odds ratio [95% confidence interval], 0.94 [0.89–1.00] per 1 kcal/kg/day increase) was independently associated with a low PhA in males. Our study revealed that lower total energy intake independently impacted low PhA in older males.

Aims: Despite the reported success of low‐carbohydrate diets in improving glycemic control in the Western countries, no studies have investigated the effects of such diets in Asians. We aimed to conduct a systematic review and meta‐analysis of randomized controlled trials to examine the effects of low‐carbohydrate diets on glycemic control in East Asian adults.Materials and Methods: We systematically searched the PubMed, Cochrane Library, and Embase databases from inception to June 28, 2023, to identify randomized controlled trials examining the efficacy of low‐carbohydrate diets in patients with type 2 diabetes (PROSPERO number CRD 42023453007). The primary outcome was the difference in glycated hemoglobin levels between the low‐carbohydrate diet and control groups. The secondary outcome was the difference in body mass index, fasting blood glucose level, blood pressure, and lipid profile.Results: Six randomized controlled trials met the eligibility criteria. The study duration ranged from 3 to 18 months, with five studies conducted within 6 months. The results showed that low‐carbohydrate diets were more beneficial in lowering glycated hemoglobin levels and body mass index than control diets. The risk of bias for the six studies was minimal for two and moderate for four. The heterogeneity among the studies was low.Conclusions: Low‐carbohydrate diets improved glycated hemoglobin levels and body mass index in East Asians compared with control diets. Therefore, carbohydrate restriction may be effective for glycemic management in East Asians with type 2 diabetes for at least 6 months.