Nutritional management and autism spectrum disorder: A systematic review

Table 2 The differences between the specific carbohydrate diet and the gut and psychology syndrome diet

Aspect	Specific carbohydrate diet	Gut and psychology syndrome diet
Origins and development	Developed by Dr. Sidney V. Haas in the 1920s	Developed by Dr. Natasha Campbell-McBride in 2004
Original purpose	Treatment of celiac disease and gastrointestinal disorders	Addressing neurological and psychological conditions
Popularized by	Elaine Gottschall, through "Breaking the Vicious Cycle"	Dr. Campbell-McBride, through "Gut and Psychology Syndrome"
Focus	Elimination of specific carbohydrates to reduce gut dysbiosis	Healing gut lining, restoring healthy gut flora, reducing inflammation
Principles	Excludes complex carbohydrates, lactose, and sucrose	Focuses on healing the gut lining, restoring gut flora
	Includes easily digestible foods	Eliminates processed foods, refined sugars, starchy vegetables
	Emphasizes nutrient-dense foods	Structured in distinct phases
Main foods	Meat, fish, eggs, vegetables, fruits, nuts, certain dairy products	Similar to SCD, with greater emphasis on bone broth, fermented foods, healthy fats
Foods excluded	All grains, starchy vegetables, lactose (initially), sucrose, processed foods	All grains, starchy vegetables, refined sugars, processed foods, certain dairy products
Diet structure	More flexible, with less emphasis on phases	Structured in phases: Introductory phase to full GAPS diet
Emphasis on healing	Eliminating specific carbohydrates to reduce gut dysbiosis	Healing the gut lining and restoring healthy gut flora
Food focus	Eliminating specific carbohydrates	Healing foods like bone broth and fermented foods
Underlying philosophy	Specific carbohydrates promote gut dysbiosis	Gut health linked to psychological and neurological health
Target conditions	Celiac disease, gastrointestinal disorders, IBD, ASD	ASD, ADHD, depression, psychological and neurological conditions
Overall approach	Straightforward food elimination	Phased approach with emphasis on gut healing

This table summarizes the key differences between the specific carbohydrate diet and the gut and psychology syndrome diet, highlighting their distinct origins, principles, and implementation strategies. IBD: Inflammatory bowel disease; ASD: Autism spectrum disorder; ADHD: Attention deficit hyperactivity disorder; GAPS: Gut and psychology syndrome; SCD: Specific carbohydrate diet.