Lemon and blood pressure
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Lemon Juice and Blood Pressure: Human Studies
Several studies have examined whether lemon juice can lower blood pressure in people with hypertension. Most human studies found that drinking lemon juice does not significantly reduce blood pressure, either in the short term or after regular use over weeks. In controlled trials, both lemon juice and water led to small, temporary drops in systolic blood pressure, likely due to the calming effect of the clinical environment rather than the lemon itself. No significant long-term benefit was observed, and researchers caution that lemon juice may interact with some blood pressure medications and could lead to noncompliance with prescribed treatments if used as an alternative therapy 12.
Some studies combined lemon juice intake with walking and found a significant reduction in blood pressure among hypertensive individuals. However, these studies suggest that the effect may be due to the combination of lemon juice and physical activity, rather than lemon juice alone. The improvement in blood pressure was correlated with both increased steps and lemon intake, indicating that both factors may contribute through different mechanisms 89.
Lemon Aromatherapy and Blood Pressure
Research on lemon aromatherapy (inhaling lemon oil vapors) in elderly hypertensive patients showed a significant reduction in both systolic and diastolic blood pressure compared to a control group. This suggests that lemon aromatherapy may have a calming effect that helps lower blood pressure in older adults . Another study using essential lemon oil products also suggested a potential benefit for blood pressure relief, though these findings are preliminary and require further research .
Fermented Lemon Juice and Blood Pressure: Animal Studies
Animal studies have shown that lemon juice, especially when fermented with lactic acid bacteria, can significantly lower blood pressure in hypertensive rats. The fermentation process increases the levels of gamma-aminobutyric acid (GABA), a compound known for its calming effects on the nervous system, which may help stabilize heart rate and reduce blood pressure . Additionally, citric acid, the main component of lemon juice, was identified as the primary antihypertensive agent in these animal models, with both lemon juice and citric acid causing marked reductions in blood pressure .
Lemon Water Infusion and Blood Pressure
A study using lemon-infused water (lemon and cucumber) in hypertensive adults found a reduction in both systolic and diastolic blood pressure after eight days of daily intake. However, the difference between the intervention and control groups was not statistically significant, suggesting that while there may be a mild effect, it is not strong enough to be conclusive .
Conclusion
Current evidence from human studies does not support a strong blood pressure-lowering effect of lemon juice alone. Some benefit may be seen when lemon juice is combined with physical activity or used as aromatherapy, but more research is needed to confirm these effects. Animal studies suggest that certain compounds in lemon, such as citric acid and GABA (from fermentation), may help lower blood pressure, but these findings have not been clearly replicated in humans. People with hypertension should consult their healthcare provider before using lemon or lemon products as a treatment, especially if they are taking medication.
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