Oral saline or tasty saline: Which one should you take and when

Summer in Bangladesh means unbearable heat, sweating, and physical weakness. During this time, one piece of advice is heard everywhere — "Have saline." But which saline? Oral saline or tasty saline? Are they the same thing? When is each needed? Without knowing the answers to these questions, taking saline can sometimes cause harm instead of benefit. So, it is important to understand the matter in some depth.

How does the body's water and salt balance work?
Approximately 60 per cent of the human body is water. This water exists both inside and outside cells. The most important role in maintaining this water balance is played by certain ions or electrolytes — particularly sodium (Na⁺), potassium (K⁺), chloride (Cl⁻), and bicarbonate (HCO₃⁻).

What happens to the body in intense heat?
In extreme heat, the body produces sweat to cool itself. This is a natural thermoregulation process. When sweat evaporates from the skin, heat is released from the body. However, this process does not just remove water — it also removes sodium, chloride, potassium, and other minerals.

Research has shown that a person can sweat between half a litre and two litres per hour, and each litre of sweat contains 30 to 70 milliequivalents of sodium. When working in the sun or exercising for long periods, a significant amount of sodium is lost from the body.

Oral saline: It is a medicine, not just a drink
Oral saline is used to reduce deaths from diarrhoea and dehydration. The mixture contains sodium chloride, sodium citrate, potassium chloride, and anhydrous glucose, which creates a solution close to the osmolarity of blood, allowing the body to absorb it very easily and quickly.

In cases of severe dehydration from diarrhoea or vomiting in summer, extreme weakness after prolonged sun exposure, or early symptoms of heatstroke such as dizziness, nausea, or risk of fainting, oral saline is needed.

Oral saline packets available in the market should be mixed with 500 ml of water. If mixed with the wrong amount of water, it may not be effective.

Tasty saline: What does it contain and how effective is it?
Tasty saline is essentially a commercial flavoured electrolyte drink. While it contains some sodium, potassium and chloride, the amount and ratio are not the same as oral saline. The biggest difference is that it contains much higher amounts of sugar and comparatively lower sodium.

From a scientific perspective, excessive sugar increases the osmolarity of the solution. Such a solution may sometimes draw water out of the intestines instead of absorbing it, which can be dangerous when consumed during hot weather.

What else can you do to stay healthy?
In addition to saline, drink at least 8-10 glasses of water daily, even if you do not feel thirsty. Coconut water is naturally rich in potassium and electrolytes. You can also eat water-rich fruits such as watermelon, cucumber, and oranges.