Chicken slaughterhouse byproducts — particularly feet, blood, and bones — yield peptides that inhibit ACE and lower blood pressure in animal studies, but human trials are still needed.
ACE inhibition from chicken wasteProtein hydrolysates from chicken feet, blood, bones, and skin demonstrated angiotensin-converting enzyme inhibitory activity and lowered blood pressure in animal models
What the researchers found
Multiple chicken slaughterhouse byproducts — including blood, bones, skins, and especially chicken feet — can be enzymatically broken down into protein hydrolysates containing peptides with ACE-inhibitory activity and blood pressure-lowering effects in animal models. The underlying mechanisms include increased endogenous antioxidant levels, reduced ACE activity, and improved endothelial dysfunction. However, clinical confirmation in humans is still lacking.
Why it matters
Hypertension is the leading preventable cause of cardiovascular death worldwide, and new approaches to managing it are needed. Food-derived bioactive peptides offer a natural, potentially low-cost alternative or complement to pharmaceutical ACE inhibitors. Using chicken slaughterhouse waste as a peptide source simultaneously addresses a health need and a sustainability challenge by turning low-value byproducts into functional ingredients.
How the study worked
Narrative review evaluating published research on the extraction and characterization of antihypertensive peptides from chicken slaughterhouse byproducts (blood, bones, skins, feet). The review assessed ACE-inhibitory activity data, blood pressure outcomes in animal models, and proposed mechanisms of action across the existing literature.
What this study cannot tell us
The vast majority of cited studies used animal models (primarily spontaneously hypertensive rats), with very limited human clinical data. Bioavailability, dose-response relationships, and long-term safety of these peptides in humans remain uncharacterized. The enzymatic hydrolysis conditions vary widely across studies, making direct comparison of peptide potency difficult.
How to read the evidence
This is a narrative review summarizing primarily preclinical (animal model) research. While the ACE-inhibitory and antihypertensive effects are consistently reported across multiple studies, the absence of human clinical trials significantly limits the translational evidence grade.
When this study was published
Published in 2023, this review captures the current state of a relatively young field. The lack of human clinical data noted by the authors may have been partially addressed by newer studies since publication.
The bigger picture
Food-derived bioactive peptides are a growing field at the intersection of nutrition science, pharmacology, and sustainability. Peptides from dairy, fish, and plant sources have already reached the market as functional food ingredients. Chicken byproducts represent a massive untapped resource — billions of kilograms of processing waste generated globally each year. If the antihypertensive effects translate to humans, these peptides could become part of the broader movement toward food-as-medicine while reducing agricultural waste.
Questions still open
- Will the ACE-inhibitory peptides from chicken byproducts survive digestion and maintain their blood pressure-lowering effects when consumed orally by humans?
- How do the potency and bioavailability of chicken-derived antihypertensive peptides compare to established food-derived peptides from dairy (e.g., casein-derived IPP and VPP)?
- Could standardized chicken peptide hydrolysates be developed into functional food products or supplements with clinically validated blood pressure benefits?
Common questions
Can chicken feet really help lower blood pressure?
What are bioactive peptides from food?
Read the original research
Valorization of Chicken Slaughterhouse Byproducts to Obtain Antihypertensive Peptides.
Nutrients, 15(2)
Citation
Bravo, Francisca Isabel; Calvo, Enrique; López-Villalba, Rafael A; Torres-Fuentes, Cristina; Muguerza, Begoña; García-Ruiz, Almudena; Morales, Diego. (2023). Valorization of Chicken Slaughterhouse Byproducts to Obtain Antihypertensive Peptides.. Nutrients, 15(2). https://doi.org/10.3390/nu15020457