on August 25, 2026
Arterial hypertension is a condition characterized by a persistent increase in the pressure exerted by the blood on the walls of the arteries. It is not simply a high numerical value detected occasionally: the diagnosis requires repeated assessment and, when possible, confirmation through home measurements or 24-hour blood pressure monitoring.
The latest European guidelines have maintained the value of 140/90 mmHg as the diagnostic threshold for hypertension in the clinic, while identifying values between 120-139 mmHg systolic and/or 70-89 mmHg diastolic as “elevated blood pressure”. For home measurement, an average of ≥135/85 mmHg is considered equivalent to the clinic threshold of ≥140/90 mmHg. The guidelines also emphasize the importance of measurements outside the clinic to confirm the diagnosis and avoid errors due, for example, to white-coat hypertension or masked hypertension.
Systolic blood pressure, or “top” pressure, represents the pressure reached during heart contraction; diastolic pressure, or “bottom” pressure, corresponds instead to the pressure present in the arteries during the heart's relaxation phase.
The clinical importance of hypertension derives above all from its ability to cause vascular alterations and organ damage over time. The chronic increase in pressure subjects the heart, arteries, brain, kidneys, and retina to continuous mechanical and biological stress, promoting vascular remodeling, atherosclerosis, left ventricular hypertrophy, kidney disease, and an increased risk of stroke, heart attack, and heart failure.
For this reason, blood pressure management cannot be limited to simply reducing a number: it must be part of a comprehensive cardiovascular prevention strategy.
Blood pressure is the result of many mechanisms
Blood pressure depends on the interaction between cardiac output and peripheral vascular resistance. These parameters are influenced by the sympathetic nervous system, the renin-angiotensin-aldosterone system, endothelial function, plasma volume, kidney function, sodium and potassium metabolism, and numerous genetic and environmental factors.
Diet and lifestyle can interfere with many of these systems simultaneously.
A high sodium intake, for example, promotes water retention and an increase in extracellular volume, while a diet rich in potassium can promote renal sodium excretion and positively influence vascular function. Regular physical activity improves endothelial function, insulin sensitivity, and autonomic regulation, while weight loss reduces several neuro-hormonal mechanisms involved in hypertension.
The consequence is that seemingly simple changes can produce cumulative pressure effects.
Salt and sodium: one of the most effective interventions
Reducing sodium intake is one of the best-documented dietary interventions.
The large randomized, controlled DASH-Sodium study demonstrated that sodium reduction leads to a decrease in blood pressure in both normotensive and hypertensive individuals. The effect was found to be even greater when sodium reduction was combined with a DASH diet, characterized by a high consumption of fruit, vegetables, whole grains, fish, nuts, and other foods rich in nutrients favorable to blood pressure control. In hypertensive participants, switching from a high-sodium control diet to a low-sodium DASH diet resulted in an average reduction in systolic pressure of approximately 11.5 mmHg.
A meta-analysis of 133 randomized studies, including over 12,000 participants, subsequently confirmed that a reduction in sodium intake is associated with an average decrease in systolic pressure of approximately 4.3 mmHg and diastolic pressure of approximately 2.1 mmHg.
It is important to consider that the sodium introduced through the diet does not come solely from salt added at the table. A significant portion can come from processed foods, baked goods, cured meats, aged cheeses, canned goods, sauces, and other industrial products.
The most effective strategy is therefore to simultaneously reduce added salt and naturally sodium-rich foods.
The sodium-potassium ratio
It is not only about how much sodium is consumed, but also the ratio between sodium and potassium.
Potassium is found mainly in fruit, vegetables, legumes, tubers, nuts, and other plant-based foods. Several randomized trials have shown a reduction in blood pressure following an increase in potassium intake, with a generally greater effect in hypertensive people and those who consume high amounts of sodium.
A meta-analysis of 23 randomized trials conducted in subjects with hypertension found an average reduction of approximately 4.25 mmHg in systolic pressure and 2.53 mmHg in diastolic pressure with potassium supplementation compared to control.
This does not mean that potassium supplements should be used independently. In the presence of kidney disease, treatment with ACE inhibitors, sartans, aldosterone antagonists, or other medications that affect potassium metabolism, excessive intake can be dangerous.
For most people, the preferred strategy is to increase potassium through naturally rich plant-based foods, always taking into account individual clinical conditions.
DASH diet and Mediterranean model
The DASH diet is one of the most studied dietary patterns in the prevention and control of hypertension. Its fundamental principle is not the elimination of a single food, but the construction of a comprehensive dietary pattern rich in plant-based foods, fruit, whole grains, legumes, nuts, fish, and quality protein sources, with a reduction in salt, processed meats, saturated fats, sugars, and ultra-processed foods.
In the original DASH trial, the diet resulted in a significant reduction in blood pressure compared to the control diet. In subjects with hypertension, the effect was particularly evident.
A well-structured Mediterranean diet can also be part of a blood pressure control strategy, especially when combined with sodium reduction. A randomized trial published in 2023 compared the DASH diet and the Mediterranean diet, both combined with salt restriction, in adults with normal-high blood pressure or grade 1 hypertension. The study confirmed the usefulness of the structured dietary intervention compared to control.
The most important message is therefore that the overall quality of the diet matters more than the search for a single “anti-hypertensive food”.
Body weight and blood pressure
The relationship between body weight and blood pressure is particularly close.
Excess adipose tissue is associated with increased sympathetic activity, alterations in the renin-angiotensin-aldosterone system, insulin resistance, low-grade chronic inflammation, and alterations in endothelial function. Weight loss can simultaneously intervene in several of these mechanisms.
A meta-analysis of 35 studies including over 3,200 overweight or obese people found that weight reduction is associated with a significant decrease in blood pressure. An average reduction in BMI of approximately 2.27 kg/m² was associated with a decrease in systolic pressure of approximately 5.8 mmHg and diastolic pressure of approximately 3.4 mmHg.
A previous meta-analysis of 25 randomized trials found that a weight loss of approximately 5 kg was associated with an average reduction of 4.4 mmHg in systolic and 3.6 mmHg in diastolic pressure.
It is therefore not necessarily required to pursue an extreme weight reduction: even a moderate weight loss maintained over time can have favorable consequences on blood pressure.
Movement: a true anti-hypertensive intervention
Regular physical activity represents one of the most effective tools to modify blood pressure without exclusively resorting to pharmacological therapy.
Aerobic exercise promotes vasodilation, improved endothelial function, increased cardiorespiratory capacity, and favorable changes in sympathetic activity. The effect does not depend exclusively on weight loss: physically active people can achieve blood pressure benefits even without significant changes in body mass.
A dose-response meta-analysis of 34 randomized trials, including 1,787 adults with hypertension, found that each additional 30 minutes of weekly aerobic activity was associated with an average reduction of approximately 1.78 mmHg in systolic and 1.23 mmHg in diastolic blood pressure. The estimated maximum effect was observed at around 150 minutes per week, with a reduction of approximately 7.2 mmHg in systolic and 5.6 mmHg in diastolic blood pressure.
Strength training also showed favorable effects. An analysis of 84 randomized trials conducted on over 5,000 hypertensive people found that overall exercise reduced systolic blood pressure by approximately 7.5 mmHg and diastolic by approximately 4.4 mmHg, with no substantial differences in the magnitude of the effect between the different types of exercise analyzed.
For this reason, the most useful movement is not necessarily a specific sport: brisk walking, cycling, swimming, running, aerobic exercise, and strength training can be incorporated into a personalized program.
Green tea: a measurable but modest effect
Green tea contains catechins, including epigallocatechin-3-gallate (EGCG), a polyphenol that has been particularly studied for its biological properties.
The potential cardiovascular effects can be attributed to the modulation of oxidative stress and endothelial function, as well as possible effects on nitric oxide bioavailability.
A 2025 meta-analysis of 36 randomized trials found an average reduction in systolic blood pressure of 1.08 mmHg and diastolic of 1.09 mmHg with green tea supplementation. However, the authors highlighted the heterogeneity of the studies and described the overall effect as modest.
A previous meta-analysis of 24 trials and 1,697 participants had obtained similar results, with reductions of approximately 1.2 mmHg for both systolic and diastolic blood pressure.
Green tea can therefore be considered a component of a cardioprotective diet, but not a substitute for antihypertensive therapy.
In addition, caffeine content should be considered in individuals who are particularly sensitive to stimulants or in whom caffeine causes transient increases in blood pressure.
Grapes and grape seed polyphenols
Grapes, especially those with a rich polyphenol component, contain flavonoids and proanthocyanidins concentrated particularly in the grape seeds.
A meta-analysis of 16 randomized trials, involving a total of 810 participants, found that grape seed extracts reduced average systolic blood pressure by approximately 6.1 mmHg and diastolic by 2.8 mmHg. The effects were more pronounced in some subgroups, including younger individuals, overweight people, and participants with metabolic syndrome.
The data is interesting, but it must be interpreted correctly: the studies mainly involved standardized grape seed extracts, not the simple occasional consumption of fresh grapes. It is therefore not possible to attribute the same quantitative effect to the whole food as was observed with an extract used in the trials.
Fresh grapes remain, however, a food consistent with a diet rich in fruits and vegetables, while extracts should be considered separately from a pharmacological and safety perspective.
Hibiscus: one of the most studied plants for blood pressure
Hibiscus sabdariffa, commonly known as hibiscus, is particularly interesting for its anthocyanin, organic acid, and other polyphenol content.
A 2015 meta-analysis based on five randomized trials involving a total of 390 participants found a reduction in systolic blood pressure of approximately 7.6 mmHg and diastolic of approximately 3.5 mmHg compared to the control.
A subsequent meta-analysis in 2021 included 13 randomized trials and 1,205 participants, confirming a reduction in systolic blood pressure of approximately 6.7 mmHg and diastolic of approximately 4.4 mmHg compared to placebo in people with mild-to-moderate hypertension. However, hibiscus did not outperform antihypertensive medications in head-to-head comparisons.
This data makes hibiscus one of the most interesting plant substances in nutritional research on blood pressure, but even in this case, the effect should be considered complementary.
Walnuts and nuts
Nuts are a particularly interesting food for cardiovascular prevention due to the presence of unsaturated fatty acids, fiber, magnesium, potassium, and polyphenols.
Walnuts, in particular, can contribute to improving the lipid profile and vascular function. However, their effect on blood pressure appears less pronounced and less uniformly documented than that of sodium restriction or physical activity.
A serving of approximately 30 g per day can therefore fit into a cardioprotective diet, provided it preferably consists of unsalted nuts. This last aspect is essential: walnuts and other nuts coated in salt can significantly increase sodium intake, going in the opposite direction of the goal.
Flaxseeds: alpha-linolenic acid, lignans, and fiber
Flaxseeds contain a particularly interesting combination of alpha-linolenic acid (ALA), fiber, and lignans, molecules that can affect vascular function, lipid metabolism, and the gut microbiota.
A meta-analysis of 11 studies involving 14 trials found an average reduction in systolic blood pressure of approximately 1.77 mmHg and diastolic of 1.58 mmHg after supplementation with flaxseed-based products.
A subsequent meta-analysis of 15 trials, involving 1,302 participants, observed reductions of approximately 2.85 mmHg in systolic and 2.39 mmHg in diastolic blood pressure.
In this case too, the effect is quantitatively more limited than that obtainable with an overall strategy of sodium reduction, physical activity, and weight loss, but incorporating flaxseeds into a balanced diet can contribute to the overall cardiometabolic profile.
What to limit: alcohol and high-sodium foods
Among lifestyle changes, reducing alcohol is particularly important in individuals who consume large quantities.
Alcohol can increase blood pressure through several mechanisms, including changes in sympathetic activity, alterations in the renin-angiotensin system, and increased energy intake. The most recent international guidelines recommend reducing or avoiding alcohol as part of the prevention and treatment of hypertension.
Similarly, habitual consumption of high-sodium foods should be limited, particularly cold cuts, preserved products, salty snacks, very aged cheeses, bouillon cubes, certain sauces, and numerous ultra-processed products.
Caffeine, licorice, and stimulants
Not all plant substances are appropriate when it comes to blood pressure.
Licorice, in particular, can increase blood pressure by inhibiting the enzyme 11β-hydroxysteroid dehydrogenase type 2, consequently increasing the mineralocorticoid activity of cortisol. High or prolonged consumption can lead to hypertension, fluid retention, and hypokalemia.
Concentrated extracts containing stimulating substances must also be evaluated with caution in hypertensive individuals. The issue therefore does not concern “adaptogenic plants” generically, but rather the specific composition of the extract, the dosage, pharmacological interactions, and the individual characteristics of the patient.
Accurate blood pressure measurement is part of a healthy lifestyle
A lifestyle intervention is difficult to evaluate without accurate blood pressure measurement.
European guidelines recommend, where possible, supplementing office blood pressure measurement with home blood pressure monitoring or 24-hour blood pressure monitoring. This makes it possible to identify different situations:
- sustained hypertension, when blood pressure is elevated both in the office and outside the office;
- white-coat hypertension, when blood pressure is elevated in the office but not outside the office;
- masked hypertension, when blood pressure appears normal in the office but is elevated under normal living conditions.
Masked hypertension is particularly important because it may escape diagnosis while being associated with a higher cardiovascular risk than office blood pressure measurement alone would suggest. The 2024 guidelines therefore recommend using out-of-office measurements, where possible, to confirm hypertension.
When lifestyle changes are not enough
Lifestyle represents a fundamental component of treatment, but must not be used as an automatic alternative to pharmacological therapy.
Current ESC guidelines recommend, in patients with confirmed hypertension ≥140/90 mmHg, combining lifestyle interventions with pharmacological therapy when indicated. Behavioral changes may subsequently allow, in some adequately monitored patients, a reduction in therapy or the number of medications, but this decision must be made by the physician based on blood pressure trends.
The 2025 American Heart Association recommendations similarly emphasize the importance of maintaining a healthy body weight, a heart-healthy diet, reducing sodium intake, ensuring adequate potassium intake, physical activity, stress management, and reducing or eliminating alcohol consumption.
Pharmacological therapy should therefore not be interpreted as a failure of lifestyle: in patients for whom it is indicated, it represents an essential tool for reducing cardiovascular risk.
A dietary pattern more effective than searching for a single food
Scientific research suggests that the most effective approach to hypertension is not to search for a single food capable of “lowering blood pressure,” but to build a coherent set of behaviors.
A cardiovascular-healthy day can therefore include a diet rich in vegetables, fruit, legumes, whole grains, fish, unsalted nuts, and extra virgin olive oil, a significant reduction in high-sodium foods, adequate potassium intake through food, regular physical activity, weight control, moderation or abstinence from alcohol, and smoking cessation.
Within this pattern, foods and beverages studied for their possible effect on blood pressure can find a place, such as green tea, hibiscus, grapes, berries, and flaxseed. However, available evidence indicates that their effect is generally modest or variable and cannot be equated to that of an antihypertensive medication.
The real benefit comes from combining multiple interventions: reducing sodium, improving dietary quality, increasing physical activity, and maintaining an appropriate body weight act on different but convergent mechanisms.
Blood pressure as a parameter of cardiovascular health
Hypertension should not be considered merely as a disease to “treat” when the value exceeds a certain threshold. Blood pressure is also an important indicator of overall vascular and metabolic status.
A progressively increasing value over time can represent an early sign of alterations involving body weight, renal function, glucose metabolism, sympathetic activity, sodium-potassium balance, and endothelial function.
Intervening before hypertension becomes persistent can therefore have a particularly important preventive value. The combination of accurate home monitoring, quality diet, sodium reduction, physical activity, and weight control today constitutes one of the cornerstones of cardiovascular prevention.
Clinical research confirms that these changes are not merely generic advice: they can produce measurable reductions in blood pressure. The goal is not to replace medicine with diet, but to use every available tool to reduce the overall cardiovascular load and maintain an efficient cardiovascular system for as long as possible.
Main bibliographic references
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