2005

Physiol Res. 2005;54(1):33-9.
Short-term very low calorie diet reduces oxidative stress in obese type 2 diabetic patients.
Skrha J, Kunesova M, Hilgertova J, Weiserova H, Krizova J, Kotrlikova E.
Third Department of Internal Medicine, First Faculty of Medicine, Charles University, U nemocnice 1, 128 08 Prague 2, Czech Republic.

Oxidative stress is higher in obese diabetic than in non-diabetic subjects. This pilot study evaluates oxidative stress during short-term administration of a very low calorie diet in obese persons. Nine obese Type 2 diabetic patients (age 55+/-5 years, BMI 35.9+/-1.9 kg/m2) and nine obese non-diabetic control subjects (age 52+/-6 years, BMI 37.3+/-2.1 kg/m2) were treated by a very low calorie diet (600 kcal daily) during 8 days stay in the hospital. Serum cholesterol, triglycerides, non-esterified fatty acids (NEFA), beta-hydroxybutyrate (B-HB), ascorbic acid (AA), alpha-tocopherol (AT), plasma malondialdehyde (MDA) and superoxide dismutase (SOD) activity in erythrocytes were measured before and on day 3 and 8 of very low calorie diet administration. A decrease of serum cholesterol and triglyceride concentrations on day 8 was associated with a significant increase of NEFA (0.30+/-0.13 vs. 0.47+/-0.11 micromol/l, p<0.001) and B-HB (0.36+/-.13 vs. 2.23+/-1.00 mmol/l, p<0.001) in controls but only of B-HB (1.11+/-0.72 vs. 3.02+/-1.95 mmol/l, p<0.001) in diabetic patients. A significant decrease of plasma MDA and serum AT together with an increase of SOD activity and AA concentration (p<0.01) was observed in control persons, whereas an increase of SOD activity (p<0.01) was only found in diabetic patients after one week of the very low calorie diet. There was a significant correlation between NEFA or B-HB and SOD activity (p<0.01). We conclude that one week of a very low calorie diet administration decreases oxidative stress in obese non-diabetic but only partly in diabetic persons. Diabetes mellitus causes a greater resistance to the effects of a low calorie diet on oxidative stress.

Metabolism. 2005 Jun;54(6):705-12.
Two days of a very low calorie diet reduces endogenous glucose production in obese type 2 diabetic patients despite the withdrawal of blood glucose-lowering therapies including insulin.
Jazet IM, Pijl H, Frolich M, Romijn JA, Meinders AE.

Abstract The mechanism of the blood glucose-lowering effect of a 2-day very low calorie diet (VLCD; 1890 kJ/d) in combination with the cessation of all blood glucose-lowering agents was studied in 12 (7 women, 5 men) obese (body mass index, 36.3 +/- 1.0 kg/m 2 [mean +/- SEM]) type 2 diabetic patients (age, 55 +/- 4 years; HbA 1c , 7.3% +/- 0.4%) undergoing insulin therapy. Endogenous glucose production (EGP) and whole body glucose disposal (6,6 2 H 2 -glucose), lipolysis ( 2 H 5 -glycerol), and substrate oxidation (indirect calorimetry) rates were measured before and after the intervention in basal and hyperinsulinemic conditions. After 2 days of a VLCD and discontinuation of all blood glucose-lowering therapies, fasting plasma glucose levels did not increase (11.3 +/- 1.3 vs 10.3 +/- 1.0 mmol/L). Basal EGP significantly declined (14.2 +/- 1.0 to 11.9 +/- 0.7 mu mol/kg per minute; P = .009). Basal metabolic clearance rate of glucose and rate of basal lipolysis did not change. During hyperinsulinemia, EGP (5.5 +/- 0.8 to 5.2 +/- 0.5 mu mol/kg per minute), whole body glucose disposal (12.1 +/- 0.7 to 11.3 +/- 1.0 mu mol/kg per minute), the metabolic clearance rate of glucose, and the rate of lipolysis did not change after the 2-day intervention. Cessation of blood glucose-lowering therapy in combination with a 2-day VLCD does not lead to hyperglycemia and is associated with a reduction in basal EGP. Insulin-stimulated whole body glucose disposal did not improve, nor did insulin suppressibility of EGP and lipolysis.

Cochrane Database Syst Rev. 2005 Apr 18;(2):CD004095.
Long-term non-pharmacologic weight loss interventions for adults with type 2 diabetes.
Norris S, Zhang X, Avenell A, Gregg E, Brown T, Schmid Ch, Lau J.
Center for Outcomes and Evidence, Agency for Healthcare, Research and Quality, 540 Gaithers Road, Room 6325, Rockville, MD, USA, 20850.

BACKGROUND: Most persons with type 2 diabetes are overweight and obesity worsens the metabolic and physiologic abnormalities associated with diabetes. OBJECTIVES: The objective of this review is to assess the effectiveness of lifestyle and behavioral weight loss and weight control interventions for adults with type 2 diabetes. SEARCH STRATEGY: Studies were obtained from computerized searches of multiple electronic bibliographic dababases, supplemented with hand searches of selected journals and consultation with experts in obesity research. The last search was conducted May, 2004. SELECTION CRITERIA: Studies were included if they were published or unpublished randomized controlled trials in any language, and examined weight loss or weight control strategies using one or more dietary, physical activity, or behavioral interventions, with a follow-up interval of at least 12 months. DATA COLLECTION AND ANALYSIS: Effects were combined using a random effects model. MAIN RESULTS: The 22 studies of weight loss interventions identified had a 4,659 participants and follow-up of 1 to 5 years. The pooled weight loss for any intervention in comparison to usual care among 585 subjects was 1.7 kg (95 % confidence interval [CI] 0.3 to 3.2), or 3.1% of baseline body weight among 517 subjects. Other main comparisons demonstrated nonsignificant results: among 126 persons receiving a physical activity and behavioral intervention, those who also received a very low calorie diet lost 3.0 kg (95% CI -0.5 to 6.4), or 1.6% of baseline body weight, more than persons receiving a low-calorie diet. Among 53 persons receiving identical dietary and behavioral interventions, those receiving more intense physical activity interventions lost 3.9 kg (95% CI -1.9 to 9.7), or 3.6% of baseline body weight, more than those receiving a less intense or no physical activity intervention. Comparison groups often achieved significant weight loss (up to 10.0 kg), minimizing between-group differences. Changes in glycated hemoglobin generally corresponded to changes in weight and were not significant when between-group differences were examined. No data were identified on quality of life and mortality. AUTHORS' CONCLUSIONS: Weight loss strategies using dietary, physical activity, or behavioral interventions produced small between-group improvements in weight. These results were minimized by weight loss in the comparison group, however, and examination of individual study arms revealed that multicomponent interventions including very low calorie diets or low calorie diets may hold promise for achieving weight loss in adults with type 2 diabetes.

2004

Diabetes Res Clin Pract. 2004 Sep;65(3):235-41.
Beneficial effect of low carbohydrate in low calorie diets on visceral fat reduction in type 2 diabetic patients with obesity.
Miyashita Y, Koide N, Ohtsuka M, Ozaki H, Itoh Y, Oyama T, Uetake T, Ariga K, Shirai K.
Center of Diabetes, Endocrine and Metabolism, Sakura Hospital, School of Medicine, Toho University, 564-1 Shimoshizu, Sakura-City, Chiba 285-0841, Japan.

The adequate composition of carbohydrate and fat in low calorie diets for type 2 diabetes mellitus patients with obesity is not fully established. The aim of this study was to investigate the effects of low carbohydrate diet on glucose and lipid metabolism, especially on visceral fat accumulation, and comparing that of a high carbohydrate diet. Obese subjects with type 2 diabetes mellitus were randomly assigned to take a low calorie and low carbohydrate diet (n = 11, 1000 kcal per day, protein:carbohydrate:fat = 25:40:35) or a low calorie and high carbohydrate diet (n = 11, 1000 kcal per day, protein:carbohydrate:fat = 25:65:10) for 4 weeks. Similar decreases in body weight and serum glucose levels were observed in both groups. Fasting serum insulin levels were reduced in the low carbohydrate diet group compared to the high carbohydrate diet group (-30% versus -10%, P < 0.05). Total serum cholesterol and triglyceride levels decreased in both groups, but were not significantly different from each other. High-density lipoprotein-cholesterol (HDL-C) increased in the low carbohydrate diet group but not in the high carbohydrate diet group (+15% versus 0%, P < 0.01). There was a larger decrease in visceral fat area measured by computed tomography in the low carbohydrate diet group compared to the high carbohydrate diet group (-40 cm(2) versus -10 cm(2), P < 0.05). The ratio of visceral fat area to subcutaneous fat area did not change in the high carbohydrate diet group (from 0.70 to 0.68), but it decreased significantly in the low carbohydrate diet group (from 0.69 to 0.47, P < 0.005). These results suggest that, when restrict diet was made isocaloric, a low calorie/low carbohydrate diet might be more effective treatment for a reduction of visceral fat, improved insulin sensitivity and increased in HDL-C levels than low calorie/high carbohydrate diet in obese subjects with type 2 diabetes mellitus.

Am J Med. 2004 Nov 15;117(10):762-74.
Long-term effectiveness of lifestyle and behavioral weight loss interventions in adults with type 2 diabetes: a meta-analysis.
Norris SL, Zhang X, Avenell A, Gregg E, Bowman B, Serdula M, Brown TJ, Schmid CH, Lau J.
Divisions of Diabetes Translation, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia, USA.

BACKGROUND: Most persons with type 2 diabetes are overweight, and obesity worsens the metabolic and physiologic abnormalities associated with diabetes. Our objective was to assess the effectiveness of lifestyle and behavioral weight loss and weight control interventions in adults with type 2 diabetes. METHODS: Studies were obtained from searches of multiple electronic bibliographic databases, supplemented with hand searches of selected journals and consultation with experts in obesity research. Studies were included if they were published or unpublished randomized controlled trials in any language that examined weight loss or weight control strategies using one or more dietary, physical activity, or behavioral interventions, with a follow-up interval of at least 12 months. Effects were combined using a random-effects model. RESULTS: The 22 studies of weight loss interventions identified yielded a total of 4659 participants with a follow-up of 1 to 5 years. The pooled weight loss for any intervention in comparison with usual care among 585 subjects was 1.7 kg (95% confidence interval [CI]: 0.3 to 3.2 kg), or 3.1% of baseline body weight among 511 subjects. Among 126 persons who underwent a physical activity and behavioral intervention, those who also received a very low-calorie diet lost 3.0 kg (95% CI: -0.5 to 6.4 kg), or 1.6% of baseline body weight, more than persons who received a low-calorie diet. Among 53 persons who received identical dietary and behavioral interventions, those who received a more intense physical activity intervention lost 3.9 kg (95% CI: -1.9 to 9.7 kg), or 3.6% of baseline body weight, more than those who received a less intense or no physical activity intervention. Comparison groups often achieved substantial weight loss (up to 10.0 kg), minimizing between-group differences. Changes in glycated hemoglobin level generally corresponded to changes in weight and were not substantial when between-group differences were examined. CONCLUSION: Weight loss strategies involving dietary, physical activity, or behavioral interventions were associated with small between-group improvements in weight. These results were minimized by weight loss in the comparison group, however, and examination of individual study arms revealed that multicomponent interventions, including very low-calorie diets or low-calorie diets, may hold promise for achieving weight loss in adults with type 2 diabetes.

2001

Am J Physiol Endocrinol Metab 2001 Oct;281(4):E757-65
Dietary restriction and glucose regulation in aging rhesus monkeys: a follow-up report at 8.5 yr.
Gresl TA, Colman RJ, Roecker EB, Havighurst TC, Huang Z, Allison DB, Bergman RN, Kemnitz JW.
Wisconsin Regional Primate Research Center, Madison 53715, USA.

In a longitudinal study of the effects of moderate (70%) dietary restriction (DR) on aging, plasma glucose and insulin concentrations were measured from semiannual, frequently sampled intravenous glucose tolerance tests (FSIGTT) in 30 adult male rhesus monkeys. FSIGTT data were analyzed with Bergman's minimal model, and analysis of covariance revealed that restricted (R) monkeys exhibited increased insulin sensitivity (S(I), P < 0.001) and plasma glucose disappearance rate (K(G), P = 0.015), and reduced fasting plasma insulin (I(b), P < 0.001) and insulin response to glucose (AIR(G), P = 0.023) compared with control (C; ad libitum-fed) monkeys. DR reduced the baseline fasting hyperinsulinemia of two R monkeys, whereas four C monkeys have maintained from baseline, or subsequently developed, fasting hyperinsulinemia; one has progressed to diabetes. Compared with only the normoinsulinemic C monkeys, R monkeys exhibited similarly improved FSIGTT and minimal-model parameters. Thus chronic DR not only has protected against the development of insulin resistance in aging rhesus monkeys, but has also improved glucoregulatory parameters compared with those of otherwise normoinsulinemic monkeys.

1999

Autoimmunity 1999;30(4):243-50
Intermittent feeding and fasting reduces diabetes incidence in BB rats.
Pedersen CR; Hagemann I; Bock T; Buschard K.
Bartholin Instituttet, Kommunehospitalet, Copenhagen, Denmark.

Food intake may be one of several factors which influence the risk of development of insulin dependent diabetes mellitus, but the influence of the pattern of food supply has not been studied previously. The aim of the present study was to investigate the effect of intermittent feeding and fasting upon diabetes in BB rats. This study included three groups. Group 1 served as control and included 77 animals, 79% became diabetic. In groups 2 and 3, after weaning, food but not water was withdrawn from the animals: 24 h twice a week in group 2; 24 h every second day in group 3. Group 2 included 40 BB rats, 50% (p < 0.004) became diabetic. Group 3 included 44 BB rats, 52% (p < 0.01) became diabetic. No differences were seen between sexes. Degree of insulitis was not influenced by changed food supply. Regarding blood glucose, no influence was seen among diabetic animals, among non-diabetic animals changed food supply reduced blood glucose values obtained at the end of the study. Intermittent feeding and fasting tended to reduce mean age at the time of diagnosis of diabetes, significance was reached only in female animals from group 3 compared to group 1. Body weight was obtained weekly. Intermittent feeding and fasting caused a reduced weight gain in group 2 as well as in group 3 compared to control animals; however, most pronounced in group 3 and also more pronounced among males compared to females. For pre-diabetic and non-diabetic animals comparable influence on body weight was seen. The main conclusion in the study is that intermittent feeding and fasting reduced diabetes incidence.

2000

Diabetes Metab 2000 Jun;26 Suppl 3:46-51
Very-low-calorie-diets: is there a place for them in the management of the obese diabetic?
Monnier L; Colette C; Percheron C; Boniface H.
AUTHOR AFFILIATION: Service des Maladies Metaboliques, Hopital Lapeyronie, Montpellier.

ABSTRACT: It is well-recognized that standard caloric restrictions (1500 kcal/day) are usually poorly effective in achieving weight losses in overweight type 2 diabetic patients. For that reason very-low-calorie-diets (VLCDs) were developed as a mean for initiating or accelerating weight reduction. Short-term studies indicate that VLCDs result generally in weight losses that are three times greater than those obtained with standard low-calorie-diets. Fasting blood glucose values are improving in parallel to weight losses and in many patients the improvement in glycemic control is better than that expected from the magnitude of weight losses. However the results are rather disappointing after several months or years of follow-up. For example it has been demonstrated that weight regain can be observed as soon as the patient is shifted to a refeeding or maintenance dietary program at the end of the VLCD period. Long-term results on glycemic control and body weight reduction are generally similar with standard low-calorie-diets and with VLCDs, the final results depending on the magnitude of weight loss whatever the prescribed diet. At short-term the VLCDs can be helpful first for initiating weight losses and second for sensitizing the patient to the potential benefits of complying to dietary measures.

1998

Diabetes Metab 1998 Apr;24(2):116-23
Aggressive weight reduction treatment in the management of type 2 diabetes.
Scheen AJ.
Department of Medicine, CHU Sart Tilman, Belgium.

Most patients with Type 2 diabetes are significantly overweight, and diet-induced weight loss can provide marked improvement in their glycaemic control. As conventional therapy combining diet and exercise usually has a poor long-term success rate, more aggressive weight reduction programmes have been proposed for the treatment of severely obese diabetic patients, including very-low-calorie diets, anti-obesity drugs and bariatric surgery. Very-low-calorie diets usually have a remarkable short-term effect, and energy restriction and weight reduction are positive factors for the glycaemic control of obese diabetic subjects. However, the long-term efficacy of these methods remains doubtful since weight regain is a common phenomenon. Although anti-obesity (anorectic) drugs may help patients to follow a restricted diet and lose weight, their overall efficacy on body weight and glycaemia is generally modest, and their long-term safety still questionable. Interestingly, serotoninergic anorectic agents have been shown to improve both the insulin sensitivity and glycaemic control of obese diabetic patients independently of weight loss. Bariatric surgery may be helpful in well-selected patients. The correction of weight excess after successful gastroplasty fully reverses the abnormalities of insulin secretion, clearance and action on glucose metabolism present in markedly obese non-diabetic patients, and allows interruption or reduction of insulin therapy and antidiabetic oral agents in most obese diabetic patients. In conclusion, weight loss is a major goal in treating obese patients with Type 2 diabetes, and aggressive weight reduction programmes may be used in selected patients refractory to conventional diet and drug treatment. However, long-term prospective studies are needed for more precise determination of the role of such a strategy in the overall management of obese diabetic patients.