Visual Abstract

Objective: We aimed to evaluate the effect of weight loss induced by a carbohydrate-reduced high-protein (CRHP) diet on physical and mental health and cognition.

Methods: In this randomized parallel trial, 72 adults with type 2 diabetes and overweight or obesity (mean±SD, HbA1c: 7.4±0.7% and BMI: 33±5 kg/m2) were randomly assigned to CRHP diet (C30E%/P30E%/F40E%) or control diet (CD: C50E%/P17E%/F33E%) for 6 weeks. The two diets were intended to induce similar weight losses (~6%). Physical and mental component summary (PCS and MCS) scores were assessed from the short-form 36 questionnaire (SF-36), and global cognition, verbal memory, psychomotor speed and executive function from a neuropsychological test battery.

Results: Both groups achieved a 5.8 kg (~6%) weight loss and improved PCS (median (IQR), CD: 2.7 (1.1;4.2)% and CRHP: 2.1 (0.7;3.7)%; both p<0.001). In addition, CRHP diet improved MCS (1.8 (-0.7;5.7)%, p<0.01) and 6/8 domains of the SF-36 compared with 2/8 after the CD diet. Global and specific domains of cognition did not change within or between groups, but CD scored better on the symbol digit modality test of psychomotor speed compared to CRHP (p<0.01; Table 1).

Conclusion: Weight loss improves physical health independently of diet composition, and carbohydrate restriction may further benefit mental health, without adversely affecting overall cognition.

Disclosure

N. J. Jensen: None. S. Madsbad: Advisory Panel; Self; AstraZeneca; Boehringer Ingelheim; Eli Lilly; Merck Sharp & Dohme; Novo Nordisk; Sanofi, Research Support; Self; Novo Nordisk, Boehringer Ingelheim, Speaker’s Bureau; Self; AstraZeneca; Boehringer Ingelheim; Merck Sharp & Dohme; Novo Nordisk; Sanofi. F. Magkos: None. K. Miskowiak: Consultant; Self; Lundbeck. J. Rungby: None. S. B. Haugaard: None. T. Krarup: None. M. N. Thomsen: None. H. Z. Wodschow: None. M. J. Skytte: None. A. Samkani: None. A. Astrup: Consultant; Self; Groupe Éthique et Santé, France, Employee; Self; Novo Nordisk Foundation, Other Relationship; Self; Flaxslim ApS, Denmark, Gelesis, Personalized Weight Management Research Consortium ApS (Gluco-Diet. dk). J. Frystyk: n/a. B. Hartmann: None. J. J. Holst: Consultant; Self; Novo Nordisk, Other Relationship; Self; Antag Therapeutics, Bainan Biotech, MSD Corporation, Novo Nordisk, Other Relationship; Spouse/Partner; Antag Therapeutics, Bainan Biotech, Synklino ApS. T. M. Larsen: None.

Funding

Arla Foods; Danish Dairy Research Foundation

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. More information is available at http://www.diabetesjournals.org/content/license.