Hemp seed protein and its hydrolysate compared with casein protein consumption in adults with hypertension: a double-blind crossover study.

Background: The effects of consuming hemp seed protein (HSP) as well as its hydrolysate-derived bioactive peptide (HSP+) on blood pressure (BP) has not, to our knowledge, been investigated in humans.

Objectives: We aimed to investigate how consumption of HSP and its hydrolysate modulates 24-h systolic (SBP) and diastolic BP (DBP) and plasma biomarkers of BP compared with casein.

Methods: In a double-blind, randomized, crossover design trial, 35 adults who had mild hypertension with SBP between 130 and 160 mmHg and DBP ≤110 mmHg were recruited. Participants were randomly assigned to varying sequences of 3 6-wk treatments, 50 g casein/d, 50 g HSP/d, or 45 g HSP plus 5 g HSP-derived bioactive peptides/d (HSP+), separated by a 2-wk washout period. Treatment effects were assessed with a linear mixed model with repeated measures.

Results: Compared with casein, after HSP+ consumption, 24-h SBP and 24-h DBP decreased from 135.1 and 80.0 mmHg to 128.1 ± 1.6 (P < 0.0001) and 76.0 ± 1.4 mmHg (P < 0.0001), respectively, whereas these values were 133.5 ± 1.6 and 78.9 ± 1.4 mmHg after HSP consumption (P < 0.0001). There were no differences between the HSP and HSP+ consumption in plasma angiotensin-converting enzyme (ACE) activity, renin, or nitric oxide (NO) concentrations. However, these 2 treatments were able to lower both ACE and renin activities and raise NO concentration in plasma compared with casein.

Conclusions: These results suggest that hemp protein consumption, as well as in combination with bioactive peptides, may have a role in the dietary management of hypertension. This trial was registered at clinicaltrials.gov as NCT03508895.