Weaknesses
Scientific evidence for personalized nutrition is mostly based on observational studies with a low level of reproducibility
The theoretical basis for personalized nutrition is underdeveloped
The factors responsible for interindividual differences in response to dietary factors, their persistence over time within the same individual, and their heritability are mostly unknown
There are few well-designed randomized controlled trial that demonstrate the efficacy and safety of personalized nutrition
Most commercial offerings in the personalized nutrition area are based on direct to consumer tests that are unregulated and have limited published evidence of benefit