Effect of Low-Energy Diets Differing in Fiber, Red Meat, and Coffee Intake on Cardiac Autonomic Function in Obese Individuals With Type 2 Diabetes.

Abstract

OBJECTIVE:

The autonomic nervous system (ANS) regulates both the cardiovascular system and energy balance and is disturbed in diabetes and obesity. The effect of different approaches of caloric restriction on ANS function has not been assessed in individuals with diabetes. Thus, we sought to determine whether low-energy diets differing in fiber, red meat, and coffee intake exert differential effects on cardiac autonomic function.

RESEARCH DESIGN AND METHODS:

In this randomized parallel-group pilot trial, obese patients with type 2 diabetes were randomly allocated to consume either a diet high in cereal fiber, free of red meat, and high in coffee (n = 13) or a diet low in fiber, high in red meat, and coffee free (n = 15) over 8 weeks. Eight measures of heart rate variability (HRV) indicating vagal and/or sympathetic modulation over 3 h and inflammatory markers were determined during a hyperinsulinemic-euglycemic clamp.

RESULTS:

After 8 weeks, both dietary interventions resulted in a mean weight loss of 5-6 kg, a mean decline in heart rate of 4-6 bpm, and improvement in vagally mediated HRV. However, the changes in HRV parameters from baseline to 8 weeks did not differ between the groups. In the entire study cohort, incremental HRV from baseline to 8 weeks was associated with enhanced oxidative glucose utilization (P < 0.05), but not with insulin sensitivity and inflammatory markers.

CONCLUSIONS:

In obese patients with type 2 diabetes, energy restriction per se over 8 weeks contributed to improved cardiac vagal function in relation to improved oxidative glucose utilization. This preliminary finding should be verified in a confirmatory trial.

• Authors: Dan Ziegler, Alexander Strom, Bettina Nowotny, Lejla Zahiragic, Peter J Nowotny, Maren Carstensen-Kirberg, Christian Herder, Michael Roden
• Journal: Diabetes care (Diabetes Care) Vol. 38 Issue 9 Pg. 1750-7 (Sep 2015) ISSN: 1935-5548 [Electronic] United States
• PMID: 26070589 (Publication Type: Journal Article, Randomized Controlled Trial, Research Support, Non-U.S. Gov't)
• Copyright: © 2015 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

Chemical References

• Coffee
• Dietary Fiber

Topics

• Adult
• Autonomic Nervous System (physiopathology)
• Caloric Restriction
• Coffee
• Diabetes Mellitus, Type 2 (complications, diet therapy)
• Dietary Fiber
• Energy Metabolism (physiology)
• Female
• Humans
• Male
• Middle Aged
• Obesity (complications, drug therapy)
• Red Meat