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Effect of a 90 g/day low-carbohydrate diet on glycaemic control, small, dense low-density lipoprotein and carotid intima-media thickness in type 2 diabetic patients: An 18-month randomised controlled trial

URL: https://pubmed.ncbi.nlm.nih.gov/33017456/

Journal: PLoS One

Publication Date: 10/2020

Summary: This study explored the effect of a moderate (90 g/d) low-carbohydrate diet (LCD) in type 2 diabetes patients over 18 months. Ninety-two poorly controlled type 2 diabetes patients aged 20-80 years with HbA1c ≥7.5% (58 mmol/mol) in the previous three months were randomly assigned to a 90 g/d LCD r traditional diabetic diet (TDD). The primary outcomes were glycaemic control status and change in medication effect score (MES). The secondary outcomes were lipid profiles, small, dense low-density lipoprotein (sdLDL), serum creatinine, microalbuminuria and carotid intima-media thickness (IMT). A total of 85 (92.4%) patients completed 18 months of the trial. At the end of the study, the LCD and TDD group consumed 88.0±29.9 g and 151.1±29.8 g of carbohydrates, respectively (p < 0.05). The 18-month mean change from baseline was statistically significant for the HbA1c (-1.6±0.3 vs. -1.0±0.3%), 2-h glucose (-94.4±20.8 vs. -18.7±25.7 mg/dl), MES (-0.42±0.32 vs. -0.05±0.24), weight (-2.8±1.8 vs. -0.7±0.7 kg), waist circumference (-5.7±2.7 vs. -1.9±1.4 cm), hip circumference (-6.1±1.8 vs. -2.9±1.7 cm) and blood pressure (-8.3±4.6/-5.0±3 vs. 1.6±0.5/2.5±1.6 mmHg) between the LCD and TDD groups (p<0.05). The 18-month mean change from baseline was not significantly different in lipid profiles, sdLDL, serum creatinine, microalbuminuria, alanine aminotransferase (ALT) and carotid IMT between the groups. A moderate (90 g/d) LCD showed better glycaemic control with decreasing MES, lowering blood pressure, decreasing weight, waist and hip circumference without adverse effects on lipid profiles, sdLDL, serum creatinine, microalbuminuria, ALT and carotid IMT than TDD for type 2 diabetic patients.

 

Beneficial effects of ketogenic diet in obese diabetic subjects

URL: https://link.springer.com/article/10.1007%2Fs11010-007-9448-z

Journal: Molecular and Cellular Biochemistry

Publication Date: 04/2007

Summary: Obesity is closely linked to the incidence of type II diabetes. It is found that effective management of body weight and changes to nutritional habits especially with regard to the carbohydrate content and glycemic index of the diet have beneficial effects in obese subjects with glucose intolerance. Previously we have shown that ketogenic diet is quite effective in reducing body weight. Furthermore, it favorably alters the cardiac risk factors even in hyperlipidemic obese subjects. In this study the effect of ketogenic diet in obese subjects with high blood glucose level is compared to those with normal blood glucose level for a period of 56 weeks. A total of 64 healthy obese subjects with body mass index (BMI) greater than 30, having high blood glucose level and those subjects with normal blood glucose level were selected in this study. The body weight, body mass index, blood glucose level, total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, urea and creatinine were determined before and at 8, 16, 24, 48, and 56 weeks after the administration of the ketogenic diet. The body weight, body mass index, the level of blood glucose, total cholesterol, LDL-cholesterol, triglycerides, and urea showed a significant decrease from week 1 to week 56 (P < 0.0001), whereas the level of HDL-cholesterol increased significantly (P < 0.0001). Interestingly these changes were more significant in subjects with high blood glucose level as compared to those with normal blood glucose level. The changes in the level of creatinine were not statistically significant. This study shows the beneficial effects of ketogenic diet in obese diabetic subjects following its long-term administration. Furthermore, it demonstrates that in addition to its therapeutic value, low carbohydrate diet is safe to use for a longer period of time in obese diabetic subjects.

The effect of a low-carbohydrate, ketogenic diet on nonalcoholic fatty liver disease: a pilot study

URL: https://link.springer.com/article/10.1007%2Fs10620-006-9433-5

Journal: Digestive Diseases and Sciences

Publication Date: 02/2007

Summary: Nonalcoholic fatty liver disease is an increasingly common condition that may progress to hepatic cirrhosis. This pilot study evaluated the effects of a low-carbohydrate, ketogenic diet on obesity-associated fatty liver disease. Five patients with a mean body mass index of 36.4 kg/m2 and biopsy evidence of fatty liver disease were instructed to follow the diet (<20 g/d of carbohydrate) with nutritional supplementation for 6 months. Patients returned for group meetings biweekly for 3 months, then monthly for the second 3 months. The mean weight change was −12.8 kg (range 0 to −25.9 kg). Four of 5 posttreatment liver biopsies showed histologic improvements in steatosis (P=.02) inflammatory grade (P=.02), and fibrosis (P=.07). Six months of a low-carbohydrate, ketogenic diet led to significant weight loss and histologic improvement of fatty liver disease. Further research is into this approach is warranted.

Effects of a high-protein ketogenic diet on hunger, appetite, and weight loss in obese men feeding ad libitum

URL: https://academic.oup.com/ajcn/article/87/1/44/4633256

Journal: American Journal of Clinical Nutrition

Publication Date: 01/2008

Summary: Altering the macronutrient composition of the diet influences hunger and satiety. Studies have compared high- and low-protein diets, but there are few data on carbohydrate content and ketosis on motivation to eat and ad libitum intake. We aimed to compare the hunger, appetite, and weight-loss responses to a high-protein, low-carbohydrate [(LC) ketogenic] and those to a high-protein, medium-carbohydrate [(MC) nonketogenic] diet in obese men feeding ad libitum. Seventeen obese men were studied in a residential trial; food was provided daily. Subjects were offered 2 high-protein (30% of energy) ad libitum diets, each for a 4-wk period-an LC (4% carbohydrate) ketogenic diet and an MC (35% carbohydrate) diet-randomized in a crossover design. Body weight was measured daily, and ketosis was monitored by analysis of plasma and urine samples. Hunger was assessed by using a computerized visual analogue system. Ad libitum energy intakes were lower with the LC diet than with the MC diet [P=0.02; SE of the difference (SED): 0.27] at 7.25 and 7.95 MJ/d, respectively. Over the 4-wk period, hunger was significantly lower (P=0.014; SED: 1.76) and weight loss was significantly greater (P=0.006; SED: 0.62) with the LC diet (6.34 kg) than with the MC diet (4.35 kg). The LC diet induced ketosis with mean 3-hydroxybutyrate concentrations of 1.52 mmol/L in plasma (P=0.036 from baseline; SED: 0.62) and 2.99 mmol/L in urine (P<0.001 from baseline; SED: 0.36). In the short term, high-protein, low-carbohydrate ketogenic diets reduce hunger and lower food intake significantly more than do high-protein, medium-carbohydrate nonketogenic diets.

The effect of a low-carbohydrate, ketogenic diet versus a low-glycemic index diet on glycemic control in type 2 diabetes mellitus

URL: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2633336/

Journal: Nutrition and Metabolism

Publication Date: 12/2008

Summary: Dietary carbohydrate is the major determinant of postprandial glucose levels, and several clinical studies have shown that low-carbohydrate diets improve glycemic control. In this study, we tested the hypothesis that a diet lower in carbohydrate would lead to greater improvement in glycemic control over a 24-week period in patients with obesity and type 2 diabetes mellitus. Eighty-four community volunteers with obesity and type 2 diabetes were randomized to either a low-carbohydrate, ketogenic diet (<20 g of carbohydrate daily; LCKD) or a low-glycemic, reduced-calorie diet (500 kcal/day deficit from weight maintenance diet; LGID). Both groups received group meetings, nutritional supplementation, and an exercise recommendation. The main outcome was glycemic control, measured by hemoglobin A1c. Forty-nine (58.3%) participants completed the study. Both interventions led to improvements in hemoglobin A1c, fasting glucose, fasting insulin, and weight loss. The LCKD group had greater improvements in hemoglobin A1c (-1.5% vs. -0.5%, p = 0.03), body weight (-11.1 kg vs. -6.9 kg, p = 0.008), and high density lipoprotein cholesterol (+5.6 mg/dL vs. 0 mg/dL, p < 0.001) compared to the LGID group. Diabetes medications were reduced or eliminated in 95.2% of LCKD vs. 62% of LGID participants (p < 0.01). Dietary modification led to improvements in glycemic control and medication reduction/elimination in motivated volunteers with type 2 diabetes. The diet lower in carbohydrate led to greater improvements in glycemic control, and more frequent medication reduction/elimination than the low glycemic index diet. Lifestyle modification using low carbohydrate interventions is effective for improving and reversing type 2 diabetes.

Comparison of Low Fat and Low Carbohydrate Diets on Circulating Fatty Acid Composition and Markers of Inflammation

URL: https://link.springer.com/article/10.1007/s11745-007-3132-7

Journal: Lipids

Publication Date: 11/2007

Summary: Abnormal distribution of plasma fatty acids and increased inflammation are prominent features of metabolic syndrome. We tested whether these components of metabolic syndrome, like dyslipidemia and glycemia, are responsive to carbohydrate restriction. Overweight men and women with atherogenic dyslipidemia consumed ad libitum diets very low in carbohydrate (VLCKD) (1504 kcal:%CHO:fat:protein = 12:59:28) or low in fat (LFD) (1478 kcal:%CHO:fat:protein = 56:24:20) for 12 weeks. In comparison to the LFD, the VLCKD resulted in an increased proportion of serum total n-6 PUFA, mainly attributed to a marked increase in arachidonate (20:4n-6), while its biosynthetic metabolic intermediates were decreased. The n-6/n-3 and arachidonic/eicosapentaenoic acid ratio also increased sharply. Total saturated fatty acids and 16:1n-7 were consistently decreased following the VLCKD. Both diets significantly decreased the concentration of several serum inflammatory markers, but there was an overall greater anti-inflammatory effect associated with the VLCKD, as evidenced by greater decreases in TNF-α, IL-6, IL-8, MCP-1, E-selectin, I-CAM, and PAI-1. Increased 20:4n-6 and the ratios of 20:4n-6/20:5n-3 and n-6/n-3 are commonly viewed as pro-inflammatory, but unexpectedly were consistently inversely associated with responses in inflammatory proteins. In summary, a very low carbohydrate diet resulted in profound alterations in fatty acid composition and reduced inflammation compared to a low fat diet.

Dietary carbohydrate restriction induces a unique metabolic state positively affecting atherogenic dyslipidemia, fatty acid partitioning, and metabolic syndrome

URL: https://www.sciencedirect.com/science/article/abs/pii/S0163782708000167?via%3Dihub

Journal: Progress in Lipids Research

Publication Date: 09/2008

Summary: Abnormal fatty acid metabolism and dyslipidemia play an intimate role in the pathogenesis of metabolic syndrome and cardiovascular diseases. The availability of glucose and insulin predominate as upstream regulatory elements that operate through a collection of transcription factors to partition lipids toward anabolic pathways. The unraveling of the details of these cellular events has proceeded rapidly, but their physiologic relevance to lifestyle modification has been largely ignored. Here we highlight the role of dietary input, specifically carbohydrate intake, in the mechanism of metabolic regulation germane to metabolic syndrome. The key principle is that carbohydrate, directly or indirectly through the effect of insulin, controls the disposition of excess dietary nutrients. Dietary carbohydrate modulates lipolysis, lipoprotein assembly and processing and affects the relation between dietary intake of saturated fat intake and circulating levels. Several of these processes are the subject of intense investigation at the cellular level. We see the need to integrate these cellular mechanisms with results from low-carbohydrate diet trials that have shown reduced cardiovascular risk through improvement in hepatic, intravascular, and peripheral processing of lipoproteins, alterations in fatty acid composition, and reductions in other cardiovascular risk factors, notably inflammation. From the current state of the literature, however, low-carbohydrate diets are grounded in basic metabolic principles and the data suggest that some form of carbohydrate restriction is a candidate to be the preferred dietary strategy for cardiovascular health beyond weight regulation.

Carbohydrate restriction as the default treatment for type 2 diabetes and metabolic syndrome

URL: https://www.tandfonline.com/doi/abs/10.1080/14017430802014838?journalCode=icdv20

Journal: Scandinavian Cardiovascular Journal

Publication Date: 02/2008

Summary: Dietary carbohydrate restriction in the treatment of diabetes and metabolic syndrome is based on an underlying principle of control of insulin secretion and the theory that insulin resistance is a response to chronic hyperglycemia and hyperinsulinemia. As such, the theory is intuitive and has substantial experimental support. It has generally been opposed by health agencies because of concern that carbohydrate will be replaced by fat, particularly saturated fat, thereby increasing the risk of cardiovascular disease as dictated by the so-called diet-heart hypothesis. Here we summarize recent data showing that, in fact, substitution of fat for carbohydrate generally improves cardiovascular risk factors. Removing the barrier of concern about dietary fat makes carbohydrate restriction a reasonable, if not the preferred method for treating type 2 diabetes and metabolic syndrome. We emphasize the ability of low carbohydrate diets to improve glycemic control, hemoglobin A1C and to reduce medication. We review evidence that such diets are effective even in the absence of weight loss.

Carbohydrate Restriction has a More Favorable Impact on the Metabolic Syndrome than a Low Fat Diet

URL: https://link.springer.com/article/10.1007/s11745-008-3274-2

Journal: Lipids

Publication Date: 12/2008

Summary: We recently proposed that the biological markers improved by carbohydrate restriction were precisely those that define the metabolic syndrome (MetS), and that the common thread was regulation of insulin as a control element. We specifically tested the idea with a 12-week study comparing two hypocaloric diets (~1,500 kcal): a carbohydrate-restricted diet (CRD) (%carbohydrate:fat:protein = 12:59:28) and a low-fat diet (LFD) (56:24:20) in 40 subjects with atherogenic dyslipidemia. Both interventions led to improvements in several metabolic markers, but subjects following the CRD had consistently reduced glucose (−12%) and insulin (−50%) concentrations, insulin sensitivity (−55%), weight loss (−10%), decreased adiposity (−14%), and more favorable triacylglycerol (TAG) (−51%), HDL-C (13%) and total cholesterol/HDL-C ratio (−14%) responses. In addition to these markers for MetS, the CRD subjects showed more favorable responses to alternative indicators of cardiovascular risk: postprandial lipemia (−47%), the Apo B/Apo A-1 ratio (−16%), and LDL particle distribution. Despite a threefold higher intake of dietary saturated fat during the CRD, saturated fatty acids in TAG and cholesteryl ester were significantly decreased, as was palmitoleic acid (16:1n-7), an endogenous marker of lipogenesis, compared to subjects consuming the LFD. Serum retinol binding protein 4 has been linked to insulin-resistant states, and only the CRD decreased this marker (−20%). The findings provide support for unifying the disparate markers of MetS and for the proposed intimate connection with dietary carbohydrate. The results support the use of dietary carbohydrate restriction as an effective approach to improve features of MetS and cardiovascular risk.

Effects of a low carbohydrate weight loss diet on exercise capacity and tolerance in obese subjects.

URL: https://onlinelibrary.wiley.com/doi/full/10.1038/oby.2009.134

Journal: Obesity

Publication Date: 09/2012

Summary: Dietary restriction and increased physical activity are recommended for obesity treatment. Very low carbohydrate diets are used to promote weight loss, but their effects on physical function and exercise tolerance in overweight and obese individuals are largely unknown. The aim of this study was to compare the effects of a very low carbohydrate, high fat (LC) diet with a conventional high carbohydrate, low fat (HC) diet on aerobic capacity, fuel utilization during submaximal exercise, perceived exercise effort (RPE) and muscle strength. Sixty subjects (age: 49.2 ± 1.2 years; BMI: 33.6 ± 0.5 kg/m2) were randomly assigned to an energy restricted (∼6–7 MJ, 30% deficit), planned isocaloric LC or HC for 8 weeks. At baseline and week 8, subjects performed incremental treadmill exercise to exhaustion and handgrip and isometric knee extensor strength were assessed. Weight loss was greater in LC compared with HC (8.4 ± 0.4% and 6.7 ± 0.5%, respectively; P = 0.01 time × diet). Peak oxygen uptake and heart rate were unchanged in both groups (P > 0.17). Fat oxidation increased during submaximal exercise in LC but not HC (P < 0.001 time × diet effect). On both diets, perception of effort during submaximal exercise and handgrip strength decreased (P ≤ 0.03 for time), but knee extensor strength remained unchanged (P > 0.25). An LC weight loss diet shifted fuel utilization toward greater fat oxidation during exercise, but had no detrimental effect on maximal or submaximal markers of aerobic exercise performance or muscle strength compared with an HC diet. Further studies are required to determine the interaction of LC diets with regular exercise training and the long‐term health effects.

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