Can a Low-Salt Diet be Harmful for Your Health?

The worry about high blood pressure or heart disease usually prompts a reduction in salt consumption.

NHS guidelines recommend adults have no more than 6g of salt per day.

Cutting back on sodium is helpful but sticking to a very low-salt diet for a long time can also have unexpected effects on your health.

According to Senior Consultant Dr Prabhat Ranjan Sinha, sodium plays an important role in maintaining fluid balance, nerve function and muscle activity.

When intake drops too low for an extended period, the body’s delicate electrolyte equilibrium can be disrupted.

Dr Sinha explained: “Sodium is essential for maintaining blood volume, regulating blood pressure, and enabling nerve conduction and muscle contraction.”

He adds that chronically low sodium intake can lead to reduced blood pressure and poor kidney regulation of body fluids.

“Over time, this places stress on hormonal systems such as the renin, angiotensin, aldosterone pathway, which works to conserve sodium in the body.”

In more severe cases, prolonged sodium deficiency can lead to hyponatremia, a condition in which sodium levels in the blood drop dangerously low.

This can affect brain function and may cause confusion, weakness, reduced stamina and impaired physical performance.

Dr Sinha said: “Yes, sudden and drastic salt reduction can trigger noticeable symptoms.”

He noted that sodium is vital for transmitting nerve impulses and supporting muscle contractions.

A rapid drop in sodium levels can cause blood pressure to fall, reducing blood flow to the brain and leading to dizziness, lightheadedness and fatigue. Electrolyte imbalance can also interfere with muscle fibres, resulting in cramps or spasms.

Additionally, the kidneys may not adapt quickly to the change, which can worsen fluid imbalance and contribute to persistent tiredness and poor concentration.

Dr Sinha explains that athletes and individuals who engage in intense physical activity lose significant amounts of sodium through sweat and may develop deficiencies if intake is overly restricted.

He adds that people with conditions such as adrenal insufficiency, chronic kidney disease, or those taking diuretics should be particularly cautious.

In these groups, excessive salt restriction can increase the risk of dehydration, weakness, falls and electrolyte disturbances.

Rather than eliminating salt, Dr Sinha recommends focusing on moderation.

He advises reducing sodium from processed and packaged foods, one of the most significant contributors to excess intake, while allowing natural sodium from home-cooked meals.

Dr Sinha added: “Sodium needs vary depending on climate, physical activity levels and individual health conditions.

“Paying attention to warning signs such as persistent fatigue, dizziness, or muscle cramps can help guide adjustments.”

“For people with blood pressure or kidney-related conditions, regular monitoring and medical guidance are essential.

“Salt reduction should support cardiovascular health without disrupting essential physiological processes.”

Consulting a healthcare professional can help ensure that sodium intake is balanced, thereby protecting both long-term health and daily bodily functions.