Manage Abstracts

D. Ghidanac1-3, M. Erlich1-3, Mejia. S. Blanco1,2, T.A. Khan1,2,
D. Jenkins1,2,4-6, E. Comelli1, C.W.C. Kendall1,2,7, J.L. Sievenpiper1,2,4-6;
1
Department of Nutritional Sciences, Temerty Faculty of Medicine, University of Toronto,
2
Toronto, Ontario, Canada, Toronto 3D Knowledge Synthesis and Clinical Trials Unit,
Clinical Nutrition and Risk Factor Modification Centre, St. Michael’s Hospital, Toronto,
3 4
Ontario, Canada, College of Dietitians of Ontario, Ontario, Canada, Division of
Endocrinology and Metabolism, Department of Medicine, St. Michael’s Hospital, Toronto,
5
Ontario, Canada, Department of Medicine, Temerty Faculty of Medicine, University of
6
Toronto, Toronto, Ontario, Canada, Li Ka Shing Knowledge Institute, St. Michael’s
7
Hospital, Toronto, Ontario, Canada College of Pharmacy and Nutrition, University of
Saskatchewan, Saskatoon, Saskatchewan, Canada

Cow’s milk alone and as a key feature of the Dietary Approaches to Stop Hypertension (DASH) dietary pattern reduces blood pressure (BP) in normotensive and hypertensive subjects. National dietary guidelines are shifting to advising a plant-based diet and plant-based milks are growing in popularity. Research is needed to determine if soy milk is a suitable substitute for cow’s milk for BP reduction in adults.

We conducted a systematic review and meta-analysis of randomized controlled trials (RCTs) to assess the effect of soy milk in substitution for cow's milk consumption on systolic and diastolic BP.

We searched MEDLINE, EMBASE and The Cochrane Central Register of Controlled Trials databases (through April 2022). We included RCTs of >3 weeks that assessed the impact of soy milk vs. cow's milk on BP in adults. Two independent reviewers extracted data and assessed risk of bias. A meta-analysis was performed using fixed effects models with data expressed as mean (MD) differences with 95% confidence intervals (95% CI). GRADE assessed the certainty of evidence.

Out of the 1137 studies identified, 4 met eligibility criteria in 116 participants with hypertension (n=40) and without (n=76). Of the 76 without hypertension, 29 had diabetes. Doses of soy and cow’s milk were 240 mL per day, except for 1 study that provided 500 mL twice daily. Soy milk reduced SBP by – 8.77mmHg [–11.06, -6.48mmHg] and DBP by –6.11mmHg [–8.18, –4.04mmHg] compared to cow’s milk. Certainty of evidence was low for both SBP and DBP owing to downgrades for inconsistency and imprecision.

Substitution of soy milk for cow’s milk has a moderate decreasing effect on SBP and DBP in adults. Larger and higher-quality trials are needed to improve our estimates.

These findings suggest that the substitution of soy milk for cow’s milk may lead to a reduction in BP, a major risk factor for cardiovascular disease.

Canadian Institutes of Health Research (CIHR), Government of Canada, Diabetes
Canada