The Claim

The ingestion of a soy-dairy blend results in a prolonged net amino acid balance compared to ingestion of whey protein alone, due to the combined digestion kinetics of casein (slow), soy (intermediate), and whey (fast), which sustains amino acid availability and delays the return to baseline.

Source: Soy-dairy protein blend and whey protein ingestion after resistance exercise increases amino acid transport and transporter expression in human skeletal muscle.

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
68score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

How it works
1 study reviewed
In plain English

Consuming a blend of soy and dairy proteins leads to a longer-lasting increase in amino acids in the blood compared to consuming whey protein alone, because the proteins digest at different rates and maintain amino acid levels for a longer time.

See the scientific wording

The prolonged net amino acid balance observed after soy-dairy blend ingestion is likely due to the combined digestion kinetics of casein (slow), soy (intermediate), and whey (fast), resulting in sustained amino acid availability that delays the return to baseline compared to rapidly digested whey protein alone.

Why this might work

When a blend of slow, intermediate, and fast-digesting proteins is consumed, amino acids enter the bloodstream over a longer period than with fast-digesting protein alone. This extended rise in blood amino acids keeps muscle cells supplied with building blocks, allowing them to keep pulling amino acids in and holding onto them longer, which prevents muscle breakdown and maintains a positive protein balance for more hours.

Verified mechanismbased on 1 study

What the research says

1 study

  1. Study: Soy-dairy protein blend and whey protein ingestion after resistance exercise increases amino acid transport and transporter expression in human skeletal muscle.

    When people drank a mix of soy, casein, and whey after working out, their muscles kept amino acids longer than when they drank just whey — like a slow drip vs. a quick splash. But both types helped build muscle equally.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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