Fat Versus Carbohydrate-Based Energy-Restricted Diets for Weight Loss in Patients With Type 2 Diabetes.

PURPOSE OF REVIEW: The prevalence of combined obesity and diabetes has increased dramatically in the last few decades. Although medical and surgical weight management are variably effective in addressing this epidemic, it is essential to parallel these strategies with a hypocaloric diet comprising the appropriate macronutrient composition to induce weight loss, enhance glycemic control, and improve cardiovascular risk factors. This review reports the current evidence of the role of carbohydrates and fat-based diets for weight management in patients with combined type 2 diabetes (T2D) and obesity. RECENT FINDINGS: Low-carbohydrate diets were shown to decrease postprandial glucose levels whereas high-carbohydrate, low-fat diets are considered cardio-protective. A diet with an optimal macronutrient composition remains uncertain for patients with combined T2D and obesity. Further research is still needed to define the best dietary composition that achieves the maximum benefits on weight management, glycemic control, and cardiovascular risk factors.

Multidisciplinary intensive lifestyle intervention improves markers of nonalcoholic fatty liver disease (NAFLD) in patients with type 1 diabetes and obesity: a retrospective matched-cohort study.

BACKGROUND: The prevalence of non-alcoholic fatty liver disease (NAFLD) is increasing among patients with type 1 diabetes (T1D) paralleling the increasing prevalence of obesity among this population. However, little is known about the impact of intensive lifestyle intervention (ILI) on NAFLD in patients with T1D. METHODS: Using Hepatic Steatosis Index (HSI), a noninvasive surrogate predictor of NAFLD, we retrospectively evaluated 88 adult patients with T1D and obesity after one year of participating in a 12-week ILI program in real-world clinical practice. Using the NAFLD guidelines of the American Association for the Study of Liver Diseases (AASLD), we excluded 11 participants. We matched the remaining ILI cohort (age 43 ± 12 years, females 65%, diabetes duration 22 ± 9 years, A1C 8.2 ± 0.9%, body weight 101 ± 17 kg, BMI 35.3 ± 4.9 kg/m2) in 1:1 ratio with a similar cohort of patients with T1D and obesity who received standard diabetes care (SC) at the same practice and during the same period. Matching criteria included: sex, age, BMI, A1C and duration of T1D. HSI [8 + ALT/AST + BMI (+ 2 if female, + 2 if T2D)] was calculated at baseline and after 12 months of intervention. RESULTS: At baseline, HSI was similar between the two cohorts (46.2 ± 6.1 in the ILI cohort and 44.9 ± 5.7 in the SC cohort). After 12 months, the ILI group lost an average of 5.6 ± 2.7 kg (5.8%, p < 0.05) while the SC group maintained their baseline body weight (p < 0.001 between groups). HSI decreased significantly from baseline in the ILI group (-2.7 ± 1.1, p = 0.01), but did not change in the SC group (0.6 ± 0.9, p = 0.53, p < 0.001 between groups). Percentage of patients with high likelihood of NAFLD diagnosis decreased from 100% at baseline to 88.3% in the ILI group, and was 10.4% less compared to SC (p < 0.01). Total daily insulin dose decreased in the ILI cohort compared to the SC cohort (-6.1 ± 4.2 versus 1.34 ± 4.3 units/day, p < 0.01). CONCLUSIONS: Twelve weeks of ILI improved HSI and decreased total daily insulin requirements in patients with T1D and obesity at one year. Short-term ILI should be implemented in the management of NAFLD for obese patients with type 1 diabetes.

Long-term effect of intensive lifestyle intervention on cardiometabolic risk factors and microvascular complications in patients with diabetes in real-world clinical practice: a 10-year longitudinal study.

INTRODUCTION: Intensive lifestyle intervention (ILI) has significantly reduced incidence of diabetes and improved many cardiovascular disease risk factors. We evaluated long-term effects of ILI on cardiometabolic risk factors, and microvascular and macrovascular complications among patients with diabetes in real-world clinical practice. RESEARCH DESIGN AND METHODS: We evaluated 129 patients with diabetes and obesity enrolled in a 12-week translational model of ILI. At 1 year, we divided participants into group A, who maintained <7% weight loss (n=61, 47.7%), and group B, who maintained ≥7% weight loss (n=67, 52.3%). We continued to follow them for 10 years. RESULTS: The total cohort lost an average of 10.8±4.6 kg (-9.7%) at 12 weeks and maintained an average weight loss of 7.7±10 kg (-6.9%) at 10 years. Group A maintained 4.3±9.5 kg (-4.3%) and group B maintained 10.8±9.3 kg (-9.3%) of weight loss at 10 years (p<0.001 between groups). In group A, A1c decreased from 7.5±1.3% to 6.7±0.9% at 12 weeks but rebounded to 7.7±1.4% at 1 year and 8.0±1.9% at 10 years. In group B, A1c decreased from 7.4±1.2% to 6.4±0.9% at 12 weeks then increased to 6.8±1.2% at 1 year and 7.3±1.5% at 10 years (p<0.05 between groups). Maintenance of ≥7% weight loss at 1 year was associated with a 68% lower risk of developing nephropathy for up to 10 years compared with maintenance of <7% weight loss (adjusted HR for group B: 0.32, 95% CI 0.11, 0.9, p=0.007). CONCLUSIONS: Weight reduction in patients with diabetes can be maintained for up to 10 years in real-world clinical practice. Sustained weight loss is associated with significantly lower A1c at 10 years and improvement in lipid profile. Maintenance of ≥7% weight loss at 1 year is associated with decreased incidence of diabetic nephropathy at 10 years.

Plasma Free Fatty Acids and Metabolic Effect in Type 2 Diabetes, an Ancillary Study from a Randomized Clinical Trial.

Most nutrition studies looking at the association of food with cardiometabolic markers rely on food frequency questionnaires, which are prone to recall bias. Pentadecanoic acid, heptadecanoic acid and trans-palmitoleic acid are fatty acids that are not synthesized endogenously but are obtained from the diet, particularly dairy, making them reasonable biomarkers of dairy consumption. We investigated the association of dairy fatty acid biomarkers with glycated hemoglobin (HbA1c) and cardiovascular risk factors in type 2 diabetes (T2D). In a clinical trial, 111 participants with T2D (age 58.5 ± 8.9 years, HbA1c 8.09 ± 0.96%) were randomized into three groups: a control group that maintained baseline dairy intake, a low-fat (LF) group that incorporated ≥3 servings/day of LF dairy and a high-fat (HF) group that incorporated ≥3 servings/day of HF dairy. We compared the fatty acids (FA) composition between the three groups at 24 weeks. Pentadecanoic acid and trans-palmitoleic acid increased in the HF group by 14.1% ± 5.4% and 17.5% ± 5.1%, respectively, but not in the control and LF groups (p = 0.0474 and p = 0.0025 for group-by-time interaction, respectively). Those increases were positively associated with changes in total cholesterol, very-low-density lipoprotein cholesterol VLDL-C and triglycerides but were not associated with changes in HbA1c from baseline to 24 weeks. These results suggest that the intervention was successful and that participants were likely compliant, which supports the validity of the main trial.

Effect of dairy consumption and its fat content on glycemic control and cardiovascular disease risk factors in patients with type 2 diabetes: a randomized controlled study.

BACKGROUND: Dietary Guidelines for Americans recommend the consumption of 3 servings/d of low-fat/nonfat dairy. The effects of higher dairy consumption and its fat content are unknown in patients with type 2 diabetes. OBJECTIVE: Evaluate the impact of higher consumption of high- compared with low-fat dairy on glycated hemoglobin (HbA1c), body weight, and cardiovascular disease risk factors in patients with type 2 diabetes. METHODS: We enrolled 111 subjects with type 2 diabetes (aged 58.5 ± 8.9 y, 47% females, diabetes duration 13.2 ± 8.3 y, HbA1c 8.09 ± 0.96%) who consumed <3 servings of dairy/d. We randomly assigned them into 3 groups: control group maintained baseline dairy intake, low-fat (LF) group incorporated ≥3 servings/d of LF dairy, and the high-fat (HF) group incorporated ≥3 servings/d of HF dairy. We evaluated HbA1c, body weight, BMI, body composition parameters, blood pressure (BP), lipid parameters, homeostatic model assessment of insulin resistance (HOMA-IR), and total energy and macronutrient intake at baseline, and after 12 and 24 wk. RESULTS: At 24 wk, percent energy from saturated fat increased from baseline in the HF group by 3.6%, (95% CI: 2.2, 5.1) and decreased in the LF group by -1.9% (95% CI: -3.3, -0.4). The LF group increased their percent energy from protein by 4.5% (95% CI: 2.6, 6.4), whereas the HF group decreased their percent energy from carbohydrates by -3.4% (95% CI: -0.2, -6.7). There were no differences in the mean changes in HbA1c, body weight, BMI, body composition or lipid parameters, or BP between the 3 groups at 24 wk. CONCLUSION: In patients with type 2 diabetes, increased dairy consumption to ≥3 servings/d compared with <3 servings/d, irrespective of its fat content, while maintaining energy intake has no effect on HbA1c, body weight, body composition, lipid profile, or BP. This trial was registered at clinicaltrials.gov as NCT02895867.

Dairy Consumption and Cardiometabolic Risk Factors in Patients with Type 2 Diabetes and Overweight or Obesity during Intensive Multidisciplinary Weight Management: A Prospective Observational Study.

Dairy products are integral parts of healthy diets; however, their association with cardiometabolic (CM) health among patients with type 2 diabetes (T2D) undergoing weight management is debated. We examined the relationship between dairy consumption and CM biomarkers in 45 subjects with T2D and obesity (mean age 56 ± 9 yrs, 40% female) enrolled in a 12-week intensive multidisciplinary weight management (IMWM) program. After the IMWM program (intervention phase), subjects were followed for 12 weeks (maintenance phase). We stratified subjects based on initial average dairy consumption into infrequent (IFR), less-frequent (LFR), and frequent (FR) consumers. Outcomes were assessed at baseline, 12, and 24 weeks. There were no differences between tertiles at baseline except for higher total energy intake among FR compared with IFR. HbA1c changes showed no association with dairy consumption at 12 or 24 weeks. FR Females achieved greater weight loss at 12 weeks compared with IFR peers (-4.5 kg; 95%CI: -5.5, -3.5). There was a trend towards lower HDL-C with increasing dairy consumption during the intervention phase. In subjects with T2D and overweight or obesity, dairy consumption during weight management is not associated with HbA1c changes but with lower HDL-C and with higher magnitude of weight loss among females.

Frequency of self-monitoring of blood glucose in relation to weight loss and A1C during intensive multidisciplinary weight management in patients with type 2 diabetes and obesity.

Objective: We evaluated the relationship between frequency of self-monitoring of blood glucose (SMBG) and body weight, A1C, and cardiovascular risk factors in patients with type 2 diabetes (T2D) and obesity enrolled in a 12-week intensive multidisciplinary weight management (IMWM) program. Research design and methods: We conducted a retrospective analysis of 42 patients who electronically uploaded their SMBG data over 12 weeks of an IMWM program and divided them into tertiles based on their average frequency of SMBG per day. Mean (range) SMBG frequencies were 2.3 (1.1-2.9) times/day, 3.4 (3-3.9) times/day, and 5 (4-7.7) times/day in the lowest, middle, and highest tertiles, respectively. Anthropometric and metabolic parameters were measured at baseline and after 12 weeks of intervention. Results: Participants in the highest tertile achieved a median change (IQR) in body weight of -10.4 kg (-7.6 to -14.4 kg) compared with -8.3 kg (-5.2 to -12.2 kg), and -6.9 kg (-4.2 to -8.9 kg) in the middle and lowest tertiles, respectively (p=0.018 for trend). Participants in the highest tertile had a median change (IQR) in A1C of -1.25% (-0.6 to -3.1%) compared with -0.8% (-0.3% to -2%) and -0.5% (-0.2% to -1.2%) in the middle and lowest tertiles, respectively (p=0.048 for trend). The association between change in body weight and SMBG frequency remained significant after adjusting for age, sex, baseline body mass index, diabetes duration, and use of insulin therapy. Conclusions: Increased frequency of SMBG during IMWM is associated with significantly better weight loss and improvement of A1C in patients with T2D and obesity. These findings may suggest future clinical recommendations aimed at increasing SMBG frequency to achieve the most favorable outcomes.