*By Dr. Devan
For decades, we have been told that salt is the great villain of modern health — that excessive salt intake raises blood pressure, causes heart attacks, and silently destroys arteries. Public health campaigns across the world have declared war on sodium, urging populations to cut down their salt consumption drastically. Yet, beneath this widespread belief lies a deep scientific misunderstanding. Contrary to the popular narrative, more salt — in the right context — can actually bring down blood pressure.
This statement may seem heretical to conventional medicine, but when we examine human physiology, evolutionary biology, and modern nutritional science, the truth becomes clear: salt is not the enemy. It is a vital, life-sustaining nutrient, and its deficiency — not its excess — often lies behind chronic low energy, dizziness, hormonal imbalance, and even persistent hypertension.
The Historical Misconception
The “salt raises blood pressure” theory emerged in the mid-20th century from population studies that observed a loose association between sodium intake and hypertension. However, these studies were correlational, not causal. They failed to account for numerous confounding factors like processed food consumption, sugar intake, stress, and mineral imbalance.
Later, controlled trials — including the famous INTERSALT and PURE studies — revealed a far more nuanced picture. Populations consuming too little salt often exhibited higher mortality, while moderate-to-high salt intake correlated with better cardiovascular outcomes. The body’s sodium regulation is not linear — it follows a J-shaped curve, where both too little and too much salt can harm, but an optimal middle range promotes health and stability.
Ironically, severe sodium restriction can increase blood pressure by activating powerful hormonal mechanisms designed to retain salt and water. This paradoxical phenomenon explains why some people experience dizziness, fatigue, and even worsening hypertension on low-salt diets.
The Physiology of Salt and Blood Pressure
Salt (sodium chloride) is indispensable for life. Sodium maintains blood volume, nerve conduction, muscle contraction, and acid-base balance. When sodium levels fall, the body immediately triggers the renin–angiotensin–aldosterone system (RAAS), a powerful hormonal feedback loop that raises blood pressure to preserve circulation.
Let’s understand this step by step:
Low Salt Intake → Drop in Blood Volume
Reduced sodium levels decrease extracellular fluid volume, leading to diminished blood flow and oxygen delivery.
Kidney Sensing Mechanism Activates
The kidneys sense this reduction and release renin, which triggers the conversion of angiotensinogen into angiotensin II, a potent vasoconstrictor.
Blood Vessels Narrow, Blood Pressure Rises
Angiotensin II constricts blood vessels to maintain pressure, paradoxically increasing blood pressure in response to sodium deficiency.
Aldosterone Retains Salt and Water
Aldosterone, secreted by the adrenal glands, signals the kidneys to retain sodium and excrete potassium, further altering electrolyte balance.
Thus, chronic salt restriction leads to a hyperactivated RAAS system, chronic vasoconstriction, and hormonally driven hypertension — precisely the opposite of what low-salt proponents intend.
Salt and Stress: The Hidden Link
Low salt intake doesn’t just affect the kidneys — it stresses the entire endocrine system. Sodium directly influences adrenal gland function, particularly the secretion of cortisol and aldosterone. When sodium levels are low, the adrenals are forced to work harder, leading to adrenal fatigue over time.
Cortisol, the body’s primary stress hormone, rises to preserve sodium retention, but this comes at a cost: increased systemic stress, anxiety, and inflammation. This stress-induced cortisol elevation is one reason why many people on low-sodium diets feel anxious, irritable, and weak — and why their blood pressure can paradoxically increase.
When adequate salt is reintroduced, adrenal strain reduces, cortisol normalizes, and blood vessels relax. The result? Lower blood pressure and a calmer nervous system.
The Role of Potassium: The Balancing Partner
Salt alone is not the full story — balance is. The key lies in the sodium-to-potassium ratio, not sodium alone. Ancient human diets contained a ratio of about 1:3 or 1:4 (sodium:potassium), whereas modern diets reverse this ratio, largely due to processed food devoid of potassium.
Potassium, found in fruits, vegetables, and coconut water, helps maintain intracellular fluid balance and promotes vasodilation. When potassium intake is sufficient, even moderate or high salt intake does not elevate blood pressure. Instead, the two electrolytes work synergistically to maintain cardiovascular equilibrium.
In fact, hypertension often stems from low potassium, not high sodium. Increasing dietary potassium — while maintaining normal salt intake — normalizes blood pressure in most individuals.
Salt Deficiency: The Silent Epidemic
Modern medicine rarely diagnoses salt deficiency, yet it is alarmingly common. Symptoms include:
Chronic fatigue
Low blood pressure and dizziness
Muscle cramps
Mental fog and irritability
Salt cravings
Rapid heartbeat upon standing (POTS)
Many people — especially those following low-carb, ketogenic, or fasting diets — experience these symptoms because such diets promote sodium loss through increased urine output and lower insulin levels. Without compensatory salt intake, the body struggles to maintain fluid balance, and blood pressure may drop erratically, causing compensatory spikes.
Replenishing salt in these cases often restores energy, stabilizes blood pressure, and alleviates dizziness within hours.
The Truth from Evolution
From an evolutionary standpoint, the human body was designed to conserve salt because it was scarce in prehistoric times. Early humans lost sodium through sweat while living in hot climates, and their kidneys evolved to retain it efficiently.
Now, paradoxically, in the modern world — with air conditioning, sedentary lifestyles, and low-salt diets — the body’s salt-regulating mechanisms are misfiring. We are depriving ourselves of a mineral we were never meant to restrict so drastically.
Anthropological data reveals that traditional societies with naturally high salt intake (like the Japanese and Koreans) exhibit some of the lowest rates of cardiovascular disease, despite consuming double or triple the salt recommended by modern health authorities.
Sugar, Not Salt, Is the True Culprit
It is also essential to understand that refined sugar, not salt, drives hypertension. Fructose increases uric acid levels, impairs nitric oxide production, and causes endothelial dysfunction. Excess insulin from high carbohydrate consumption leads to sodium retention, falsely implicating salt as the cause of raised blood pressure.
When sugar intake is reduced and insulin sensitivity improves, the kidneys naturally excrete sodium efficiently — even when salt intake is normal or high. Therefore, the modern epidemic of hypertension is not a “salt problem,” but a metabolic problem rooted in insulin resistance, dehydration, and mineral imbalance.
Hydration, Salt, and Blood Pressure: The Triad
Salt does not work in isolation. Its effects depend on hydration status. When adequate water accompanies salt intake, blood volume expands healthily, perfusion improves, and the body achieves balance.
Dehydration, on the other hand, concentrates sodium levels, triggering compensatory vasoconstriction. This explains why high salt with low water intake can transiently raise blood pressure — not because salt is harmful, but because it must always act in concert with hydration.
The ideal practice is to consume natural salts (such as Himalayan pink salt or sea salt), rich in trace minerals, along with plenty of water and potassium-rich foods. This combination naturally regulates pressure and prevents arterial stiffness.
Practical Implications
Don’t Fear Salt — Choose the Right Kind:
Refined table salt, stripped of minerals and laced with anti-caking agents, is not ideal. Natural salts contain magnesium, calcium, and iodine — all essential for cardiovascular and thyroid health.
Balance with Potassium:
Include bananas, avocados, spinach, and coconut water to maintain a healthy sodium-potassium equilibrium.
Hydrate Intelligently:
Aim for 2.5–3 liters of water daily, especially in hot climates or during exercise. Water without electrolytes can dilute sodium excessively.
Monitor Symptoms, Not Just Numbers:
Fatigue, dizziness, or salt cravings may signal low sodium, even if blood pressure readings appear normal.
Avoid Sugar and Processed Foods:
Refined carbohydrates — not natural salt — are the leading cause of hypertension and vascular stiffness.
A Paradigm Shift in Understanding Hypertension
The demonization of salt has been one of modern medicine’s greatest nutritional errors. What was once revered as “white gold” — essential for life and preservation — has been unjustly condemned.
The real truth is this: salt, in its natural form, is not the cause of hypertension — it is the cure for many of its underlying imbalances. When used wisely, along with adequate hydration and potassium intake, salt stabilizes the body’s electrical and hormonal systems, calms the nervous system, and lowers blood pressure naturally.
Conclusion
The human body is an exquisitely balanced electrochemical system. Sodium is not merely a seasoning — it is a conductor of life itself. Depriving the body of salt disrupts hormonal harmony, increases stress hormones, and paradoxically raises blood pressure.
By restoring salt to its rightful place — as a vital nutrient rather than a forbidden substance — we can achieve a more accurate, holistic understanding of cardiovascular health.
In truth, more salt, taken intelligently, brings down blood pressure by restoring balance — not by restriction, but by respect for the body’s natural design.
*Dr. Devan is a Mangaluru-based ENT specialist and author.
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