Mar 19, 2026
3 min read
It can cause dangerous ventricular arrhythmias, fainting or sudden death.The results are often caused by stress or exercise, but they are added to the consumption of specific foods, including grapefruit juice and energy drinks.This is what cardiologists and university researchers from the IRCCS Maugeri of Pavia, with the aim of providing useful data to prevent accidents.
Genetic heart disease is the most common cause of sudden death in people under the age of 40.Long QT syndrome (LQTS) is defined as a group of heart channels characterized by prolongation of the QT interval (the time during which the heart "charges" after contraction) on the electrocardiogram.This condition, which is determined by changes in the proteins involved in the electrical stability of the heart, is genetic in origin and dangerous.Ventricular arrhythmias can cause fainting or - in extreme cases - sudden death.
Changes in heart rate or rhythm is a condition that affects about one million people in Italy and can have serious consequences if left untreated, experts explain.
Although there is no specific data regarding long QT syndrome, according to recent estimates, 1 person in every 2000 live births suffers from the syndrome.Currently, 17 genes have been identified that, when altered, cause the disease and these forms are numbered sequentially;of them the most studied are 1, 2 and 3, because they are the forms that occur most frequently.
Taking beta-blockers and some changes in lifestyle are still the basis for the management of these diseases, risk related stress or physical exercise, but also eating certain foods, because the influence of some diet on recovery and arrhythmic risk has recently been found, especially in people with a genetic predisposition.
Possible dangers of food in new scientific analysis
Published in the journal Advances in Nutrition, a group of Italian researchers from the Department of Molecular Medicine of the University of Pavia and the Department of Molecular Cardiology at the Moggeri Scientific Clinical Institute (IRCCS, Pavia) highlight the effect of food on arrhythmias in long QT syndrome.
In this insightful work, signed by Andrea Mazzanti, Matteo Floriano, Deni Kucavica, Alessandro Trancuccio, and Silvia Priori, scientists for the first time gather mechanical and clinical evidence for the electrophysiological effects of certain nutrients, food components, and additives, including juices, juices, and products with excessive salt content. and energy drinks."This review aims to provide a structured overview of the interaction between nutritional factors and arrhythmia risk in long QT syndrome, with practical implications for treatment," the article emphasizes.
Grape Juice and Wine: Why Avoid Them?
According to the collected data, grapefruit juice (Citrus paradisi) has emerged as a clinically important food component that promotes QT prolongation due to the presence of flavonoids, namely naringenin and furanocoumarins such as bergamottin.These compounds interfere with cardiac repolarization by two means: direct inhibition of ion channels and alteration of drug metabolism.
Licorice (Glyceriza glabra) is a widely used ingredient in sweets, herbal remedies, and herbal infusions.Its bioactive compounds are associated with hypertension, hypokalemia and QT interval prolongation with electrolyte changes and direct effects on cardiac ion channels.
Be careful with quinine. Quinine is found in:
Bitter alkaloids derived from Cinchona bark, quinine are often used as flavoring agents in tonics and have medicinal applications, especially as an anti-malarial.Although generally safe in small doses, it is associated with cardiovascular disease and prolongation of the QT interval, especially in supratherapeutic doses or in prescription doses.
Dietary supplements and prolonged QT effects
Some dietary supplements may pose a significant risk of QT prolongation.Specifically, the revision applies to the following situation:
Pueraria mirifica, a Southeast Asian herbal supplement used as a natural alternative to estrogen therapy for menopause, aims to relieve symptoms.It contains phytoestrogens such as myrostrol and deoxymyrostrol, and although direct electrophysiological studies of cardiac effects are lacking, its structural and functional similarity to estradiol—which is known to have a QT interval prolonging effect—suggests possible interactions with cardiac ion channels.
Berberine, a bioactive alkaloid extracted from Coptis root and Phellodendron chinensis, is widely used in traditional Chinese and Ayurvedic medicine for the treatment of type 2 diabetes mellitus, hyperlipidemia, and hypertension.It has recently gained popularity as an over-the-counter supplement, but has been shown to inhibit hERG potassium channels, which is rarely mentioned in the product literature and poses a potential proarrhythmic risk.
I cannabinoidi, na particolare il cannabidiolo (CBD) na cannabigerolo, can have popolarita because it comes to the end;However, both show electrophysiological activity related to arrhythmogenesis.
Cesium chloride, used as an alternative cancer treatment, has been shown by the FDA for serious cardiovascular risks, including hypokalemia and arrhythmias.Its arrhythmogenic effects have sometimes been documented, including prolongation of the QT interval and polymorphic ventricular tachycardia.
"Kolat" of energy drinks.
Stimulant drinks are high in caffeine, taurine, sugar and other compounds such as guarana.The review said: "Their ability to prolong the QT interval and trigger arrhythmic events has caused concern, especially in people with long QT syndrome. Although energy drinks are associated with QT prolongation, the underlying mechanisms are not well understood. It appears that caffeine alone, even in doses up to 400 mg, does not cause QTc prolongation, and coffee consumption is not associated with QT prolongation."However, it is possible that "other substances, such as taurine and guarana, may show a synergistic or additive effect, especially when consumed in large quantities. (...) The increasing complexity and different types of systems prevent vulnerable populations."
Despite their presumed safety and widespread use, therefore, all mentioned supplements often contain bioactive compounds that interfere with cardiac ion channels or drug metabolism.Additionally, unlike the latter, dietary supplements are typically not subject to rigorous safety evaluations, which leave critical gaps in the understanding of their arrhythmic potential.
Arrhythmias and heart disease, one of the strongest research centers in the world in Pavia
At the Maugeri Scientific Clinical Institutes in Pavia, molecular cardiology has been studying hereditary arrhythmias and arrhythmogenic heart diseases for almost thirty years under the direction of Professor Silvia Priori."This is a project built over time that has joined the evolution of modern heart diseases to the current precision medicine," explains Andrea Mazzanti, Professor Professor of Cardiology at the University of Pavia, specialist in the study of hereditary arrhythmias and genetic genetic cardiomyopathies.It is thanks to this long-term experience that very significant results have been obtained today: «and the long follow-up of thousands of patients and families clarify the issue: the risk of arrhythmia is not a static fact fixed instantly and all through DNA.This is due to the strong balance between biological predisposition and modulating factors, such as treatment, environment and life," emphasizes the expert, extending the idea to the personalization of the healing process. "Today, we are used to thinking of medicine as something more organized.It is no longer an effective treatment for every person, but the decisions are made by his genes and it is known that his condition changes the life of this disease. In this new situation, even the party, the culture occupies a peripheral element that respects the heart.are re-interpreted in different ways, not as a direct cause of the disease, but as a possible part of a wider balance that helps determine the individual's risk profile".
Prof. Also, in the field of cardiology, specifically, what does "specialized therapy" mean for long QT syndrome?
"This means, first of all, the possibility of tailoring the treatment to the genotype. Particularly in long QT syndrome, we now know that different mechanisms require different treatments. In some forms linked to the SCN5A gene, the use of targeted drugs such as mexiletine has been shown to significantly reduce the risk of serious events, even affecting the mortality rate."
Is medication the only way to treat these conditions?
"Not again: apart from drugs, even the top view is opening. In the case of the most difficult inherited arrhythmias, such as catecholaminergic polymorphic ventricular tachycardia, the treatment methods have been developed with the aim of correcting the damage to the life underlying this disease. This is the state of change: from the danger that causes the intervention."
In light of these new therapeutic perspectives, what importance might nutrition have?
"Here the topic of nutrition finds its natural place. If we accept that arrhythmia risk depends on the interaction between genetics and the environment, we cannot ignore what we put in our body every day. The heart is an electrical organ. Its operation depends on a very delicate balance of ionic currents. Some substances, foods or drinks can directly affect this balance. Indirectly, in many people these effects are minimal, but in subjects with often existing electrical impairment, the weight of the same stimulus can vary."
A review study by your team also mentions the possible risks of taking natural supplements.Can you explain better?
"One of the most common misconceptions is the idea that a natural substance is directly safe. In clinical practice, we often see patients who are concerned about well-studied and controlled drugs, but who are more relaxed about taking supplements or herbal products because they are thought to be harmless. However, from a biological point of view, many natural substances have a real pharmacological effect. They can interact with the electrical balance of the heart. Cardiovascular drugs in the heart with genetics,even seemingly simple changes can be significant."
Is that why the free market needs extra special attention?
“They represent the most critical point. They are easily accessible, are often taken without medical supervision and are rarely considered “medicines” by the patient themselves.However, some of these products contain substances that may affect the repolarization of the heart or alter the effect of ongoing therapies.The problem is not demonizing supplements, but recognizing that they are not neutral.In a healthy person they may have no significant effect;in a patient with an arrhythmogenic disease may be a factor that requires careful evaluation.Together with Dr.“The review work carried out by Dr. Matteo Floriano, nutritionist, arose precisely from this need: to study thoroughly the interaction between diet, dietary supplements and cardiac arrhythmias, avoiding both alarmism and underestimation.”
The same goes for energy drinks, mentioned in the review…
"They are rich in caffeine and other stimulants and are now part of everyday habits, especially among young people. In most cases they do not cause problems, but in the presented topics they can increase tachycardia, increase electrical instability or increase the risk that already exists. The message is not taboo here either. It is informative. What you tolerate well, may not be tolerated by everyone."
In practice, can cardiovascular wellness avoid certain food choices?
"Real collaboration between cardiologists and nutritionists is essential. Those involved in nutrition should be aware that certain diet or nutritional choices can have cardiac consequences for patients with fragility. At the same time, cardiologists can not limit themselves to drug therapy regardless of the context of diet and metabolism.
How important is it to inform those living with heart disease without "alarming" them?
"Talking about nutrition and arrhythmias today does not mean creating new fears. It means awareness. Most people do not need to radically change their diet to protect their heart. But there are subgroups of patients for whom some extra attention can make a difference. Precision medicine is not only about innovative drugs or gene therapies. closer evaluation It is in this space - between advanced science and real life - today plays an important role in the prevention of cardiovascular disease.
