Low carbohydrate diet: are concerns with saturated fat, lipids, and cardiovascular disease risk justified?

Abstract Background We have previously reported that in patients with type 2 diabetes (T2D) consumption of a very low carbohydrate diet capable of inducing nutritional ketosis over 2 years (continuous care intervention, CCI) resulted in improved body weight, glycemic control, and multiple risk factors for cardiovascular disease (CVD) with the exception of an increase in low density lipoprotein cholesterol (LDL-C). In the present study, we report the impact of this intervention on markers of risk for atherosclerotic cardiovascular disease (CVD), with a focus on lipoprotein subfraction particle concentrations as well as carotid-artery intima-media thickness (CIMT). Methods Analyses were performed in patients with T2D who completed 2 years of this study (CCI; n = 194; usual care (UC): n = 68). Lipoprotein subfraction particle concentrations were measured by ion mobility at baseline, 1, and 2 years and CIMT was measured at baseline and 2 years. Principal component analysis (PCA) was used to assess changes in independent clusters of lipoprotein particles. Results At 2 years, CCI resulted in a 23% decrease of small LDL IIIb and a 29% increase of large LDL I with no change in total LDL particle concentration or ApoB. The change in proportion of smaller and larger LDL was reflected by reversal of the small LDL subclass phenotype B in a high proportion of CCI participants (48.1%) and a shift in the principal component (PC) representing the atherogenic lipoprotein phenotype characteristic of T2D from a major to a secondary component of the total variance. The increase in LDL-C in the CCI group was mainly attributed to larger cholesterol-enriched LDL particles. CIMT showed no change in either the CCI or UC group. Conclusion Consumption of a very low carbohydrate diet with nutritional ketosis for 2 years in patients with type 2 diabetes lowered levels of small LDL particles that are commonly increased in diabetic dyslipidemia and are a marker for heightened CVD risk. A corresponding increase in concentrations of larger LDL particles was responsible for higher levels of plasma LDL-C. The lack of increase in total LDL particles, ApoB, and in progression of CIMT, provide supporting evidence that this dietary intervention did not adversely affect risk of CVD.

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Alternate Day Fasting Combined with a High Protein/low Carbohydrate Diet: Effect on Body Weight and Metabolic Disease Risk Factors in Obese Adults (P21-018-19)

Current Developments in Nutrition ◽

10.1093/cdn/nzz041.p21-018-19 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

Author(s):

Faiza Kalam ◽

Kelsey Gabel ◽

Eric Wiseman ◽

Krista Varady

Keyword(s):

Blood Pressure ◽

Body Weight ◽

Fat Mass ◽

Disease Risk ◽

High Protein ◽

Obese Adults ◽

Carbohydrate Diet ◽

Low Carbohydrate Diet ◽

Low Carbohydrate ◽

Alternate Day Fasting

Abstract Objectives This pilot study is the first to examine the impact of alternate day fasting (ADF) combined with a high protein/low carbohydrate diet on body weight and metabolic disease risk factors in obese adults. Methods Obese adults (n = 10) followed an ADF diet (600 kcal fast day alternated with an ad libitum feast day; 35% protein, 22% carbohydrate, 43% fat) for 6 months. Meal replacements were consumed on the fast and feast days, in addition to regular foods, to help attain macronutrient targets. Results Body weight decreased (P < 0.001) by 8.4 ± 1.7 kg (8.6 ± 1.7%) after 6 months. Fat mass and visceral fat mass were reduced (P < 0.05) by 6.4 ± 1.6 kg and 0.2 ± 0.1 kg, respectively. Lean mass decreased (P < 0.05) by 1.3 ± 0.6 kg. Systolic blood pressure was reduced (P < 0.05) by 10 ± 3 mm Hg, and diastolic blood pressure was reduced (P < 0.05) by 6 ± 3 mm Hg. Fasting glucose, insulin, insulin resistance, and HbA1c remained unchanged after 6 months of diet. LDL cholesterol and triglyceride levels decreased (P < 0.001) by10 ± 4% and 15 ± 8%, respectively, after 6 months. HDL cholesterol levels decreased by 6 ± 3% from baseline to post-treatment. Conclusions These preliminary findings suggest that ADF combined with a high protein/low carbohydrate diet is effective for lowering body weight, visceral fat mass, blood pressure, LDL cholesterol and triglyceride levels. However, this diet has no effect on glucoregulatory factors. While these preliminary findings are promising, they still require confirmation by a larger-scale clinical trial. Funding Sources Nestle Health Sciences Grant.

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