Edible Algae Reduce Blood Pressure in Humans: A Systematic Review and Meta-Analysis of Randomised Controlled Trials

Area of Science:

• Nutritional Science
• Cardiovascular Health
• Marine Biology

Background:

• Edible algae possess bioactive compounds beneficial for cardiovascular health, including blood pressure (BP) regulation.
• Species like Nori and Kelp are rich in inorganic nitrate, known for BP-lowering effects.
• The impact of algae consumption on hypertension is debated, necessitating further research.

Purpose of the Study:

• To systematically evaluate the effects of edible algae on human blood pressure.
• To investigate the influence of algae type, dosage, duration, and participant health status on BP outcomes.

Main Methods:

• A systematic search of Medline-Pubmed, Scopus, and Cochrane databases was performed.
• Randomized controlled trials (RCTs) of at least 4-weeks duration in adults were included.
• Random-effects meta-analyses, with heterogeneity and bias assessments, were conducted.

Main Results:

• Twenty-nine RCTs involving 1583 participants showed algae intake significantly reduced systolic BP (SBP) and diastolic BP (DBP).
• Spirulina demonstrated the most significant BP reduction; dosages over 3g/day and whole algae intake were more effective.
• Benefits were more pronounced in individuals with cardiometabolic risk, and higher baseline BP predicted greater reductions.

Conclusions:

• Consuming over 3g/day of whole edible algae, especially Spirulina, for at least 12 weeks significantly lowers BP.
• Edible microalgae show potential as a natural adjunct therapy for managing hypertension.
• This approach may complement existing pharmacological treatments for elevated blood pressure.