Blood type diets lack supporting evidence: a systematic review

Area of Science:

• Nutrition Science
• Dietary Research
• Evidence-Based Medicine

Background:

• Blood type diets, based on ABO blood groups, have gained popularity over the last decade.
• These diets claim to enhance health and reduce disease risk.
• The scientific evidence supporting these claims has not been systematically evaluated.

Purpose of the Study:

• To systematically review and critically appraise published studies on blood type diets.
• To assess the scientific evidence for the effectiveness of blood type diets in improving health and decreasing disease risk.
• To identify research gaps in the validation of blood type diet claims.

Main Methods:

• A systematic literature search was conducted using sensitive strategies across major databases (Cochrane Library, MEDLINE, Embase).
• The Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach was used for critical appraisal.
• The review focused on studies investigating the health effects of adhering to specific diets based on human blood types.

Main Results:

• Out of 1415 screened references, only one article met the eligibility criteria.
• The eligible study examined LDL-cholesterol responses to a low-fat diet across different MNS blood types, not directly addressing ABO blood type diets.
• No studies were found that directly investigated the health effects of ABO blood type diets.

Conclusions:

• There is currently no scientific evidence to support the purported health benefits of blood type diets.
• Further research is needed, including comparative studies with control groups, to validate these claims.
• High-quality studies are required to assess health outcomes associated with adherence to specific blood type diets.