The digestible indispensable amino acid score (DIAAS) in eggs and egg-containing breakfast meals is greater than in toast breads or hash browns served without eggs.
Level 5 - mechanism / opinion, no new human data
Animal model (ileal-cannulated pigs) evaluating protein digestibility
PubMed 39703894 · doi:10.1017/jns.2024.71
What was done
Nine ileal-cannulated growing female pigs (gilts; initial body weight 51.1 ± 6.0 kg) were evaluated across six 7-day feeding periods in a 9 x 6 Youden square design. Nine diets were tested: six single-source protein foods (fried egg, boiled egg, scrambled egg, English muffin, Texas toast, hash brown), three combination meals (fried egg + English muffin, boiled egg + Texas toast, scrambled egg + hash brown), and one nitrogen-free diet. The standardized ileal digestibility of crude protein and amino acids was measured to calculate digestible indispensable amino acid scores (DIAAS) using reference patterns for children aged 6 to 36 months and individuals older than 3 years.
What was found
For both age reference groups, all cooked egg preparations had significantly higher DIAAS than the plant-based foods (P < 0.001). Hash browns had higher DIAAS than English muffins or Texas toast (P < 0.001). All combination meals had a DIAAS exceeding 75, with no significant difference between measured DIAAS and values predicted additively from individual ingredients. Specific numerical DIAAS values and digestibility percentages were not reported in the abstract.
Why it matters
This study demonstrates that the DIAAS of individual foods is additive in mixed meals and that incorporating eggs into carbohydrate-based breakfast foods improves overall meal protein quality.
Limits
The trial was conducted in a small animal model (n = 9 pigs) rather than in humans. Exact numerical DIAAS values, baseline digestibility scores, and measure variances were not reported in the abstract.
Cited by
- supports Based on the Digestible Indispensable Amino Acid Score (DIAAS), animal protein possesses the highest protein digestibility and protein quality found in nature.