Sindler D, Kastovska B, Dostal T, Cipryan L, Elavsky S. The effects of carbohydrate-restricted diet on psychological outcomes: a systematic review of randomized controlled trials.
Nutr Rev 2024;
82:228-239. [PMID:
37290430 DOI:
10.1093/nutrit/nuad053]
[Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023] Open
Abstract
CONTEXT
Carbohydrate-restricted diets are widely used as an effective treatment tool for many chronic diseases. The impact of these diets on physical health is well known, but their impact on psychological health is less well described in the scientific literature. This is an important aspect to focus on, especially if the diets are to be sustainable in the long term.
OBJECTIVE
The objective of this study was to systematically review the scientific literature describing the effect of carbohydrate-restricted diets and ketogenic diets on psychological outcomes, as observed in randomized controlled trials. Additionally, the potential synergistic effect of carbohydrate-restricted diets and exercise or social factors on these outcomes was researched.
DATA SOURCES
Five databases (Web of Science, PubMed, Scopus, ScienceDirect, and MEDLINE Complete) were searched without restriction of publication date.
DATA EXTRACTION
The first data extraction was made in October 2020 and the second in May 2022. Abstract screening was performed by 3 independent reviewers. The quality of studies was assessed using the Jadad scale.
DATA ANALYSIS
Sixteen randomized controlled studies were included in the analysis. Five studies focused on clinical populations, 9 on obese/overweight populations, and 2 on healthy populations; all studies examined adult people. Four psychological outcomes were identified (quality of life, mental health, mood, and fatigue), and they were examined in connection with a very low-carbohydrate or ketogenic diet.
CONCLUSION
Daily low-carbohydrate intake may not negatively affect psychological well-being, and low-carbohydrate diets and ketogenic diets are no worse than other diets in this respect. An intervention of 12 weeks or longer can bring benefits in psychological well-being. The synergistic effect of diet and exercise or social factors was not reviewed due to lack of evidence.
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