Men who had high serum concentrations of the carotenoid had significantly lower risk for any stroke (HR=0.45;
95% CI: 0.25-0.95) and ischemic stroke (HR=0.41; 95% CI: 0.17-0.97),
compared with those who had low concentrations, Jouni Karppi, PhD, of
the University of Eastern Finland in Kuopio, and colleagues reported in Neurology.
The findings remained significant even after the researchers adjusted
for age, examination year, BMI, systolic BP, smoking, serum LDL
cholesterol, diabetes and history of stroke.
Results from previous studies examining the link between
carotenoid-rich food consumption and stroke risk have been mixed,
although some have shown associations between greater consumption,
higher serum levels and lower stroke risk.
To better understand these relationships, Karppi and colleagues
examined whether serum concentrations of major carotenoids correlated
with the risk of any stroke and ischemic stroke, among 1,031 Finnish men
aged 42 to 61 years, who were participating in the longitudinal Kuopio
Ischemic Heart Disease Risk Factor study.
Serum concentrations of lycopene, alpha-carotene, beta-carotene, alpha-tocopherol and retinol were measured.
During a median follow-up of 12.1 years, 67 strokes occurred,
including 50 ischemic strokes. After adjusting for confounding
variables, the researchers found that greater serum concentrations of
lycopene, but none of the other compounds, were associated with a lower
stroke risk.
The exceptional antioxidant properties of lycopene may help explain
why this carotenoid reduces stroke risk more than others, the
researchers suggested. "Lycopene is a potent antioxidant and the most
effective quencher of singlet oxygen, and it was reported to be more
effective than beta-carotene in cell protection against hydrogen
peroxide and nitrogen dioxide radicals."
Lycopene is also known to reduce inflammation, block cholesterol
synthesis, boost immune function, and inhibit platelet aggregation and
thrombosis.
"Results of the present study show that high serum concentrations of
lycopene, as a marker of intake of tomatoes and tomato-based products,
decrease the risk of any stroke and ischemic stroke in men," the
researchers wrote. "Thus, a balanced diet including fruits and
vegetables may prevent stroke."
References
- Karppi J et al. Neurology. 2012; 79: 1540-1547.
- http://www.clinicaladvisor.com/tomatoes-may-lower-stroke-risk-in-men/article/262763/
