Whey peptides cross gut barrier and calm muscle cell stress
What it found
In lab tests, whey peptides crossed a model gut barrier and reduced free radical damage in muscle and liver cells.
Some peptides also raised a pro-inflammatory signal in immune cells.
What they found
Animal and lab studies
Peptides cross gut barrier
After simulated digestion, peptides from whey protein isolate, beta-lactoglobulin, bovine serum albumin and a milk protein sport product were found on the far side of the cell barrier. Alpha-lactalbumin and lactoferrin produced no peptides on the far side.
Amino acids reaching cells
Beta-lactoglobulin digestion gave the highest amount of free amino acids (176.5 nM) on the far side of the barrier, including branched chain and sulphur-containing amino acids.
Antioxidant effect in muscle cells
Four peptides (ALPM, GDLE, VGIN and AVEGPK) at 5 mM reduced oxidation in mouse muscle cells by 34.4% to 53%, similar to the antioxidant N-acetylcysteine.
Antioxidant effect in liver cells
Peptides ALPM, GDLE and VGIN at 5 mM reduced oxidation in human liver cells by 35% to 52.6%. One peptide, VEELKPT, was the most potent but also reduced cell viability.
Immune cell signal
Five peptides at 5 mM increased the release of the pro-inflammatory cytokine IL-1beta from activated macrophages by 131.9% to 245.5%. They did not change TNF-alpha levels.
What the authors conclude
“In vitro results indicate that consumption of whey proteins will deliver bioactive peptides to target cells.”
Also in their conclusions
- They say that in vitro results indicate that consumption of whey proteins will deliver bioactive peptides to target cells.
- They note that four of six bioavailable peptides inhibited free radicals in muscle and liver cells, but two reduced liver cell viability and five increased IL-1beta secretion.
How it was done
Health benefits are often claimed for whey proteins based on lab tests, but little is known about which peptides survive digestion and reach target cells.
They simulated digestion of whey protein isolate, beta-lactoglobulin, alpha-lactalbumin, bovine serum albumin, lactoferrin and a milk protein sport product. They then tested whether the resulting peptides crossed a Caco-2/HT-29 cell barrier and affected muscle, liver and immune cells.
What it can’t tell you
- These are lab tests using cells, not people. They cannot show what happens in the human body after eating whey.
- The study did not measure whether these peptides reach muscles or other organs in a living person.
Who paid
- Authors work at
- Teagasc Food Research Centre, Ireland; University College Dublin, Ireland; Università degli Studi di Milano, Italy
The paper
- Title
- Bovine whey peptides transit the intestinal barrier to reduce oxidative stress in muscle cells
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Corrochano AR, Ferraretto A, Arranz E, et al (2019). Bovine whey peptides transit the intestinal barrier to reduce oxidative stress in muscle cells. Food chemistry. doi:10.1016/j.foodchem.2019.03.009Free full textPubMed 30902298DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error