Hydrolysed soy protein and amino acid transport in gut cells
What it found
In lab tests using human intestinal cells, more amino acids crossed the cell layer from partially hydrolysed soy protein than from intact soy protein.
Levels were higher for every amino acid measured.
What they found
Animal and lab studies
More amino acids crossed
After 3 hours, levels of all amino acids were higher on the far side of the cell layer for hydrolysed soy protein than for nonhydrolysed soy protein, by 32% on average.
Biggest differences
The largest gaps between hydrolysed and nonhydrolysed protein were for histidine, lysine and valine.
Larger batches behaved the same
Making the soy protein hydrolysate at larger scale did not reduce its improved absorption in these cell tests.
What the authors conclude
“These data support the hypothesis that hydrolyzed soy protein may provide dietary amino acids that are more rapidly transported across the intestinal epithelium versus intact soy protein.”
Also in their conclusions
- They say the data support the idea that hydrolysed soy protein may provide dietary amino acids that are moved across the gut lining faster than intact soy protein.
- They note this could matter when quick and higher levels of amino acids are needed, such as for stimulating muscle protein synthesis.
How it was done
Protein hydrolysates have been suggested to support muscle building more than intact proteins by delivering amino acids faster for muscle protein synthesis.
Intact and partially hydrolysed soy proteins were put through simulated gut digestion, then applied to one side of Caco-2 cell layers. The liquid on the other side was collected after 3 hours and analysed for free amino acids.
What it can’t tell you
- We summarised it from the abstract only.
- These are lab tests on intestinal cells, not studies in people. They can't show how hydrolysed soy protein affects muscles or the whole body.
- The cells were exposed for 3 hours, so the results don't show what happens over longer periods.
The paper
- Title
- Partially hydrolyzed soy protein shows enhanced transport of amino acids compared to nonhydrolyzed protein across an intestinal epithelial cell monolayer
- Type
- Study
- Evidence
- Animals and lab studies
- Summarised from
- Abstract only
- Cite
- McGraw NJ, Napawan N, Toland MR, Schulze J, Tulk BM, Krul ES (2014). Partially hydrolyzed soy protein shows enhanced transport of amino acids compared to nonhydrolyzed protein across an intestinal epithelial cell monolayer. Journal of food science. doi:10.1111/1750-3841.12553PubMed 25040304DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error