The Study
Effect of soy protein from differently processed products on cardiovascular disease risk factors and vascular endothelial function in hypercholesterolemic subjects.
This study gave people different kinds of soy food and meat for a few weeks and measured their blood numbers. It found that one kind of soy drink (soymilk) made LDL cholesterol go down a tiny bit, but nothing else changed much. We can't say soy definitely fixes heart problems — we just saw a small change in one number.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Scientists tested if drinking soy milk is better for your heart than eating soybeans or soy flour — but only when everyone eats the same amount of fat, fiber, and cholesterol.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 554 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1These changes are small and likely not enough on their own to reduce heart disease risk in real life.
- 2Soy milk lowered LDL ('bad') cholesterol by 4% and raised HDL ('good') cholesterol by 1% and apoA-I by 2% compared to soy flour or whole soybeans.
- 3No other heart markers changed.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
The American journal of clinical nutrition
Year
2007
Authors
N. Matthan, S. Jalbert, L. Ausman, J. Kuvin, R. Karas, A. Lichtenstein
Related Content
Claims (6)
People who consume large amounts of animal protein and ultra-processed foods have higher levels of systemic inflammation and a higher incidence of autoimmune diseases and cardiovascular disease.
Among adults over 50 with high cholesterol, drinking soymilk for six weeks lowers LDL cholesterol by 4% compared to eating animal protein or soy flour, when overall fat, cholesterol, and fiber intake are kept the same.
In adults over 50 with high cholesterol, drinking soymilk for six weeks raises HDL cholesterol by 1% and apolipoprotein A-I by 2% compared to eating whole soybeans or soy flour, but not compared to eating animal protein, showing that the form of soy protein affects these markers regardless of total protein intake.
In adults over 50 with high cholesterol, eating soy products like soybeans, soy flour, or soymilk for six weeks does not change levels of total cholesterol, VLDL cholesterol, triglycerides, apolipoprotein B, or C-reactive protein compared to eating animal protein, when fat, cholesterol, and fiber intake are kept the same.
In adults over 50 with high cholesterol, eating soy protein for six weeks does not change vascular endothelial function compared to eating animal protein, when other dietary factors are kept the same.
In adults with high cholesterol, eating soy protein or animal protein does not change measures of heart health such as blood vessel function, as long as other dietary factors remain the same.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.