For decades, a stark, almost undeniable truth has echoed from the halls of medicine: salt is bad for you. Ask nearly any doctor, or even just a health-conscious friend, and the immediate advice is often to cut down on sodium. This seemingly immutable piece of health wisdom rests primarily on two pillars: the belief that salt inexorably raises blood pressure, and the undeniable observation that excessive sodium can exacerbate heart failure. The image of the elderly patient, gently but firmly admonished to abandon the seasoning they love, is a common one, driven by a conviction that this restriction is unequivocally life-saving. Yet, what if the foundation of this widespread medical dictate is far less solid than it appears?
Consider the argument concerning blood pressure. It's a narrative deeply intertwined with the economics of healthcare. In an industry where recurring revenue is paramount, the development of drugs that treat a "number," like blood pressure or cholesterol, has become a goldmine. The playbook is familiar: establish a target range, then progressively narrow it, thus reclassifying more and more healthy individuals as "unhealthy" and in need of lifelong medication. This is precisely what happened with blood pressure management. The consequence? Many, especially the elderly, are pushed to excessively low blood pressures, inadvertently reducing crucial blood perfusion to their organs. This, in turn, can lead to a litany of serious issues, from kidney injuries and cognitive impairment to macular degeneration and, most dangerously, falls due to light-headedness. Beyond these physical harms, the daily reality of blood pressure medications often significantly erodes quality of life, bringing fatigue and erectile dysfunction.
But what about salt's direct link to blood pressure? Here's where the conventional wisdom truly begins to fray. Remarkably, the most detailed reviews on the subject reveal that even drastic salt reduction typically yields less than a 1% reduction in blood pressure. We routinely see hospital patients receiving massive intravenous doses of sodium chloride, often ten times the recommended daily intake, with barely a ripple in their blood pressure readings. While it's true that some individuals and certain ethnicities exhibit "salt sensitivity," meaning their blood pressure responds more significantly to sodium, this by no means applies to the majority of the population. This disconnect between the widespread fear of salt and its actual physiological impact on blood pressure is striking.
The narrative of salt as a villain is further complicated by the dangers of its extreme absence. Low sodium levels, a condition known as hyponatremia, are alarmingly correlated with increased mortality. In fact, following the very salt consumption targets we are often given can increase one's risk of dying by a significant 25%. Hyponatremia is a common reason for hospital admissions, and a substantial percentage of hospitalised patients already present with dangerously low sodium levels. Studies even show that salt restriction makes hypertensive patients far more likely to develop this perilous condition. Moreover, low dietary sodium intake has been linked to a notable increase in cardiovascular disease and death, rapidly lowering cardiac output in a manner resembling traumatic shock, and contributing to tachycardia and atrial fibrillation. The irony is stark: in our quest to avoid one perceived danger, we may be inadvertently inviting another, equally, if not more, serious, one.
This brings us to the concept of the "U-shaped curve," a fundamental principle in physiology often overlooked in the rush to reduce numbers. Many health parameters, including blood pressure and electrolyte levels, do not follow a linear "more is better" or "less is better" trend. Instead, there's an optimal range, and deviations to either extreme, too high or too low, become detrimental. For salt, this means both excessively high and dangerously low sodium diets have been shown to increase the risk of death. Even for heart failure patients, traditionally urged to draconian salt restrictions, emerging data, especially from Europe, suggests that a moderate reintroduction of salt can lead to improvement, indicating they were on the "too low" side of this crucial curve.
Beyond the numbers, the science delves deeper into concepts like zeta potential. This refers to the electrical charge that determines how particles, like blood cells, disperse in fluids. Too little or too much of a charged ion, such as sodium, can disrupt this delicate balance, leading to clumped particles, poor circulation, and fluid congestion, the very issues seen in heart failure. It explains why intravenous sodium infusions can dramatically improve a patient's condition, often dismissed as simply rehydration, but more accurately due to the restoration of optimal zeta potential.
Crucially, the "salt is bad" narrative often conflates all salt with refined, processed forms found in many processed foods and restaurant meals. It's here that the discussion needs to shift from mere quantity to quality and context. The issues we associate with "salty foods" might well be due to other problematic elements in processed items, like seed oils or toxic additives. Furthermore, refined salts themselves often lack the vital minerals present in natural salts and may contain anti-caking agents that disrupt zeta potential or have undergone refining processes that introduce unhealthy chemicals. This suggests that the problem might not be salt per se, but rather the form in which we consume it.
This leads directly to a critical, often neglected aspect of the debate: the delicate balance between sodium and potassium. It's not just about how much sodium you consume, but also how much potassium accompanies it. Potassium plays a vital role in counteracting sodium's effects on blood pressure and is essential for maintaining proper cellular function and fluid balance. A diet rich in sodium but deficient in potassium, often characteristic of Western diets heavy in processed foods and light on fruits and vegetables, creates an unhealthy ionic imbalance. Thomas Riddick's work on zeta potential, suggests that potassium might be superior to sodium in maintaining optimal zeta potential, implying that our modern dietary shift from potassium-rich natural sources (like vegetables) to sodium-heavy processed foods has created a fundamental imbalance detrimental to cardiovascular health. Modern research increasingly confirms this, showing that adequate potassium alongside sodium is paramount for normalising blood pressure and overall cardiovascular well-being.
The picture that emerges from this re-evaluation is far more nuanced than the simple "salt is bad" mantra. It suggests that our collective health advice has been influenced by profitable medical interventions, rather than a holistic understanding of physiology. Salt, an ancient and essential mineral, is not inherently evil. Like many vital substances, its benefit, and indeed its danger, lies in the dose and the context, particularly in its interplay with other crucial electrolytes like potassium. The true debate isn't whether salt is bad, but how we can consume it in a way that truly supports, rather than undermines, our health.
https://www.midwesterndoctor.com/p/the-truth-about-salt-efa\
https://scitechdaily.com/startling-health-risk-normal-sodium-levels-linked-to-heart-failure/
"A major new study from Bar-Ilan University has uncovered a surprising link between higher sodium levels and serious heart conditions, even when those levels are still considered "normal." People with sodium at the upper end of the normal range were found to be significantly more likely to develop high blood pressure and heart failure, two of the most common chronic diseases as we age.
The research examined electronic health records spanning 20 years, from 2003 to 2023, covering more than 407,000 healthy adults who receive care through Leumit Healthcare Services, one of Israel's top health providers. It is one of the largest and most detailed studies ever to explore how hydration levels may impact long-term heart health. The findings were recently published in the European Journal of Preventive Cardiology.
Among the key findings:
Sodium levels of 140–142 mmol/L (still within normal range) were linked to a 13% higher risk of hypertension.
Levels above 143 mmol/L were associated with a 29% higher hypertension risk and 20% higher risk of heart failure
Nearly 60% of the healthy adult population had sodium levels in these risk-associated ranges
Sodium, which is routinely tested in standard blood tests, has long been considered normal within the 135–146 mmol/L range. But this study challenges that assumption, suggesting a strong, long-term association between higher sodium levels and cardiovascular risk, even among those considered otherwise healthy.
Controlled for Confounding Variables
These associations remained strong even after adjusting for age, sex, BMI, blood pressure, smoking, and potassium levels. The analysis excluded individuals with conditions that affect water balance to ensure a more accurate reflection of hydration-related risk.
"Our findings point to hydration as a critical and overlooked part of chronic disease prevention. A simple blood test might flag people who could benefit from basic lifestyle adjustments—like drinking more water, which reduces sodium levels," said the study's lead author, Prof. Jonathan Rabinowitz, from the Weisfeld School of Social Work at Bar-Ilan University. Rabinowitz collaborated on the research with Dr. Natalia Dmitrieva, from the National Institutes of Health (NIH).
"Hydration is often overlooked in chronic disease prevention," added Rabinowitz. "This study adds compelling evidence that staying well-hydrated may help reduce the long-term risk of serious conditions like hypertension and heart failure."
With population aging and chronic disease rates on the rise, these insights may inform future clinical guidelines, preventive screenings, and public health campaigns aimed at encouraging healthy hydration habits.
Reference: "Risk of hypertension and heart failure linked to high-normal serum sodium and tonicity in general healthcare electronic medical records" by Jonathan Rabinowitz, Mahmoud Darawshi, Nuriel Burak, Manfred Boehm and Natalia I Dmitrieva, 11 April 2025, European Journal of Preventive Cardiology.
DOI: 10.1093/eurjpc/zwaf232"