Functional foods are foods or food components that offer specific health benefits beyond basic nutritional value. Regulatory definitions vary significantly by country: the US FDA has no specific “functional food” regulatory category (health products are regulated as dietary supplements); China’s State Administration for Market Regulation (SAMR) has a “health food” registration/filing system (“blue hat” label); the EU evaluates health claims scientifically through EFSA (European Food Safety Authority).
## Evidence Hierarchy: Strong to Weak
**Strong evidence**: omega-3 fatty acids (EPA/DHA) lowering triglycerides is supported by multiple large RCTs and meta-analyses; dietary fiber (oat β-glucan) lowering LDL cholesterol has FDA-authorized health claims; folic acid preventing neural tube defects is an established nutritional intervention.
**Moderate evidence**: plant sterols/stanols lowering LDL (EU EFSA approved health claims); probiotics preventing antibiotic-associated diarrhea; metabolic benefits of green tea catechins.
**Weak/disputed evidence**: oral collagen improving skin (absorption rate and mechanism disputed); NMN (nicotinamide mononucleotide) anti-aging (effective in animal studies, preliminary human evidence); the vast majority of “superfood” claims.
## The Rise of Precision Nutrition
Precision Nutrition uses genomics, microbiomics, metabolomics, and wearable devices to provide personalized dietary recommendations rather than universal dietary guidelines. Key finding: the same food produces significantly different blood glucose responses across individuals (Weizmann Institute’s Segal team, 2015, Cell); individual genotype and gut microbiome composition are the primary determinants.
China’s “medicine-food homology” policy (certain TCM herbs approved for use in conventional foods under the Food Safety Law framework) provides a unique domestic resource pool for functional food development — including wolfberry, black sesame, coix seed, yam, and Poria cocos — all with existing TCM research foundations that also meet food regulatory requirements.
See [Gut Microbiome and Health](https://sunqi.org/gut-microbiome-health-en/) and [EFSA health claims database](https://www.efsa.europa.eu/en/topics/topic/article13-health-claims).
