Otherindependent cross-checkabstract checked I-CHK-111 standard review

Chicken protein is very well digested by humans

True Digestibility of Tryptophan in Plant and Animal Protein.

Overview

Kashyap S et al.. J Nutr 2024 · PMID 39307282 · DOI 10.1016/j.tjnut.2024.09.014

In a human tracer study, 95.9% of tryptophan from chicken meat was digested, the highest of all foods tested.

Does the study support the specific claim? No · Methodological quality: moderate

Study explained simply

What did the researchers want to find out?: What is the true ileal-equivalent digestibility of tryptophan in plant and animal proteins in humans?
How was the study done?: Human dual-isotope tracer study using intrinsically labelled proteins (banked samples)
How many people, animals or samples were studied?: chicken meat n = 6
What was actually found?: True Trp digestibility: chicken meat 95.9 +/- 2.2%, whole egg 91.4 +/- 2.6%, egg white 89.7 +/- 2.5%, goat milk 92.8 +/- 2.9%, chickpea 72.6 +/- 2.3%, whole mung bean 67.6 +/- 3.7%. Plant proteins significantly lower than animal proteins.
How large was the observed effect?: True Trp digestibility: chicken meat 95.9 +/- 2.2%, whole egg 91.4 +/- 2.6%, egg white 89.7 +/- 2.5%, goat milk 92.8 +/- 2.9%, chickpea 72.6 +/- 2.3%, whole mung bean 67.6 +/- 3.7%. Plant proteins significantly lower than animal proteins.
What do the results mean in everyday life?: Chicken is one of the most easily digested protein foods.
What are the study's limitations?: Small n per protein; One amino acid reported here; Chicken type and cooking not described in abstract
What does it say about Elawady's specific claim?: Directly contradicts 'indigestible'.
Do the results apply to Germany and Europe?: Biology is universal.
What can explicitly not be concluded from this study?: Does not test woody breast or the microbiome.

Authors: Kashyap S et al.
Journal: J Nutr
Year: 2024
Identifier: PMID 39307282 DOI 10.1016/j.tjnut.2024.09.014
Verification: verified – PubMed efetch 2026-10-26; Crossref 2026-10-26
Retracted: no
Corrections: none
Extent checked: abstract only
Conflicts of interest and funding: DBT-Wellcome Trust India Alliance (PubMed grant list)

What is the true ileal-equivalent digestibility of tryptophan in plant and animal proteins in humans?

Study design: Other – Human dual-isotope tracer study using intrinsically labelled proteins (banked samples)
Population: Healthy adults (n = 5-7 per protein)
Country: India
Period: not stated
Sample size: chicken meat n = 6
Inclusion and exclusion criteria: as described in the abstract

Exposure / intervention: 2H-intrinsically labelled chicken meat and other proteins
Comparator: U-13C spirulina reference protein
Endpoints: True tryptophan digestibility; DIAAS
Statistical methods: as reported in the abstract

Results: True Trp digestibility: chicken meat 95.9 +/- 2.2%, whole egg 91.4 +/- 2.6%, egg white 89.7 +/- 2.5%, goat milk 92.8 +/- 2.9%, chickpea 72.6 +/- 2.3%, whole mung bean 67.6 +/- 3.7%. Plant proteins significantly lower than animal proteins.
Absolute risks: not reported
Authors' conclusion: True Trp digestibility ranged from 67.6% (whole mung bean) to 95.9% (chicken meat).

Chicken meat had the highest digestibility of all proteins tested.

Direct human evidence on how well chicken protein is digested.

In a human tracer study, 95.9% of tryptophan from chicken meat was digested, the highest of all foods tested.

Multidimensional assessment
Multidimensional assessment
Authenticity of the source	verified
Methodological quality	moderate
Risk of bias	some concerns
Precision of results	moderate
Directness	direct
Reproducibility	unknown
Consistency with the overall evidence	consistent
Regional transferability	high
Adequacy of the interpretation (by the archive)	not applicable