Cruciferous vegetables lower blood pressure in adults with mildly elevated blood pressure in a randomized, controlled, crossover trial: the VEgetableS for vaScular hEaLth (VESSEL) study.

BACKGROUND: Higher cruciferous vegetable intake is associated with lower cardiovascular disease risk in observational studies. The pathways involved remain uncertain. We aimed to determine whether cruciferous vegetable intake (active) lowers 24-h brachial systolic blood pressure (SBP; primary outcome) compared to root and squash vegetables (control) in Australian adults with mildly elevated BP (SBP 120-160 mmHg inclusive). METHODS: In this randomized, controlled, crossover trial, participants completed two 2-week dietary interventions separated by a 2-week washout. Cruciferous vegetables were compared to root and squash vegetables (~ 300 g/day) consumed with lunch and dinner meals. Participants were blinded to which interventions were the active and control. Adherence was assessed using food diaries and biomarkers (S-methyl cysteine sulfoxide (SMCSO, active) and carotenoids (control)). Twenty-four-hour brachial ambulatory SBP and secondary outcomes were assessed pre- and post each intervention. Differences were tested using linear mixed effects regression. RESULTS: Eighteen participants were recruited (median (IQR) age: 68 (66-70); female: n = 16/18; mean ± SD clinic SBP: 135.9 ± 10.0 mmHg). For both interventions, 72% participants had 100% adherence (IQR: 96.4-100%). SMCSO and carotenoids were significantly different between interventions (mean difference active vs. control SMCSO: 22.93 mg/mL, 95%CI 15.62, 30.23, P < 0.0001; carotenoids: - 0.974 mg/mL, 95%CI - 1.525, - 0.423, P = 0.001). Twenty-four-hour brachial SBP was significantly reduced following the active vs. control (mean difference - 2.5 mmHg, 95%CI - 4.2, - 0.9, P = 0.002; active pre: 126.8 ± 12.6 mmHg, post: 124.4 ± 11.8 mmHg; control pre: 125.5 ± 12.1 mmHg, post: 124.8 ± 13.1 mmHg, n = 17), driven by daytime SBP (mean difference - 3.6 mmHg, 95%CI - 5.4, - 1.7, P < 0.001). Serum triglycerides were significantly lower following the active vs. control (mean difference - 0.2 mmol/L, 95%CI - 0.4, - 0.0, P = 0.047). CONCLUSIONS: Increased intake of cruciferous vegetables resulted in reduced SBP compared to root and squash vegetables. Future research is needed to determine whether targeted recommendations for increasing cruciferous vegetable intake benefits population health. TRIAL REGISTRATION: Clinical trial registry ACTRN12619001294145.  https://www.anzctr.org.au.

S-methyl cysteine sulfoxide and its potential role in human health: a scoping review.

Higher intakes of cruciferous and allium vegetables are associated with a lower risk of cardiometabolic-related outcomes in observational studies. Whilst acknowledging the many healthy compounds within these vegetables, animal studies indicate that some of these beneficial effects may be partially mediated by S-methyl cysteine sulfoxide (SMCSO), a sulfur-rich, non-protein, amino acid found almost exclusively within cruciferous and alliums. This scoping review explores evidence for SMCSO, its potential roles in human health and possible mechanistic action. After systematically searching several databases (EMBASE, MEDLINE, SCOPUS, CINAHL Plus Full Text, Agricultural Science), we identified 21 original research articles meeting our inclusion criteria. These were limited primarily to animal and in vitro models, with 14/21 (67%) indicating favorable anti-hyperglycemic, anti-hypercholesterolemic, and antioxidant properties. Potential mechanisms included increased bile acid and sterol excretion, altered glucose- and cholesterol-related enzymes, and improved hepatic and pancreatic ß-cell function. Raising antioxidant defenses may help mitigate the oxidative damage observed in these pathologies. Anticancer and antibacterial effects were also explored, along with one steroidogenic study. SMCSO is frequently overlooked as a potential mediator to the benefits of sulfur-rich vegetables. More research into the health benefits of SMCSO, especially for cardiometabolic and inflammatory-based pathology, is warranted. Human studies are especially needed.