Which water to drink when: daily, in the heat, with food and coffee

In short: for every day and for children, choose table water up to 1 g/L with little sodium, such as Icelandic Glacial or the 18.9 L bottles. After a sauna or sport, 1-2 glasses of Narzan or Essentuki No. 4 are fine, then carry on with table water. Sparkling mineral water suits dinner, while coffee needs soft water at a TDS of around 75-150 mg/L. On a salt restriction, look for water with less than 20 mg/L of sodium and discuss the choice with your doctor.

Which water should you drink every day?

For every day, choose table water: mineralisation up to 1 g/L, ideally a few hundred mg/L, and as little sodium as possible. For home and the office the 18.9 L bottles work out cheaper, and under the Thai standard that water carries no more than 500 mg/L of salts. The amount depends on the climate and how active you are: EFSA considers 2 L a day adequate for women and 2.5 L for men including the water in food, and the Phuket heat adds another 0.5-1 L on top.

• Check the mineralisation: up to 1 g/L, better still a few hundred mg/L or less
• Sodium should be as low as possible. Low-sodium table water is what you drink all day
• For home and the office the 18.9 L bottles work out cheaper. Under the Thai standard that water carries no more than 500 mg/L of salts
• EFSA considers 2 L of water a day adequate for women and 2.5 L for men including food, with 70-80% of it coming from drinks. That is for a temperate climate; the Phuket heat calls for more

In the heat, after a sauna and after sport

Sweat takes away both water and sodium, so mineral water makes sense after the steam room or a workout. One or two glasses of Narzan or Essentuki No. 4 are enough; top up the rest with table water so you do not overdo the salt. The difference between the two is large: Essentuki No. 4 carries 2000-3000 mg/L of sodium with potassium, Narzan 50-450 mg/L but more calcium and magnesium. Drink little and often: a litre downed in one go after the sauna sits heavily on the stomach.

• Sweat takes away water and sodium, so mineral water makes sense after the steam room or a workout
• One or two glasses of Narzan or Essentuki No. 4 are enough. Top up the rest with table water so you do not overdo the sodium
• Essentuki No. 4 is the saltier one: 2000-3000 mg/L of sodium with potassium. Narzan is gentler at 50-450 mg/L, but has more calcium and magnesium
• Drink little and often. A litre downed in one go after the sauna sits heavily on the stomach

With food and at the table

Meat, cheese and rich food call for sparkling water with a pronounced taste, such as naturally carbonated Narzan. Fish, seafood and wine go better with something gentler: Icelandic Glacial at 62 mg/L according to the brand, or 6ty Degrees. In a restaurant glass looks better on the table: Narzan and Essentuki No. 4 in 0.45 L bottles. Salty waters like Essentuki No. 4 are served in small portions, they are not a water for the whole evening.

• Meat, cheese and rich food go well with sparkling water that has a pronounced taste: naturally carbonated Narzan
• Fish, seafood and wine call for something gentler with low mineralisation: Icelandic Glacial or 6ty Degrees
• Glass looks better in a restaurant: Narzan and Essentuki No. 4 in 0.45 L bottles
• Salty waters like Essentuki No. 4 are served in small portions; this is not a water for the whole evening

For coffee, tea and baby food

Coffee needs soft water with a mineralisation of roughly 75-150 mg/L: a mineral water whose salts are measured in grams will give a harsh taste and scale up the machine. Green tea calls for something softer still, black tea can take a little more. Formula and baby food are made with low-mineralisation, low-sodium water, and for a child under one your paediatrician will tell you which water to use. Medicinal-table water is not used for cooking for children.

• Coffee needs soft water with a TDS of around 75-150 mg/L. A mineral water with salts measured in grams will scale up the coffee machine
• Green tea calls for softer water still, black tea can take a little more
• Formula and baby food are made with low-mineralisation, low-sodium water. For a child under one, your paediatrician will say which water to use
• Medicinal-table water is not used for cooking for children

Which water suits a salt restriction?

Look for the line marked sodium or Na + K. Under EU rules, water with less than 20 mg/L of sodium is suitable for a low-salt diet, and for anyone told to cut down on salt that is the single most important line on the label. Essentuki No. 4 does not fit this scenario at all, with up to 3 g of sodium and potassium per litre. Narzan is more moderate, but it is still worth agreeing the amount with your doctor. This is general information and regulation, not medical advice.

• Look for the line marked sodium or Na + K. Under EU rules, water with less than 20 mg/L of sodium is suitable for a low-sodium diet
• Essentuki No. 4 does not fit that case: up to 3 g of sodium with potassium per litre
• Narzan is moderate on sodium, but on a salt restriction it is still worth agreeing the amount with your doctor
• If you have to limit calcium, for instance with certain kinds of kidney stones, agree your choice of water with your doctor too. This is not medical advice

Sources

• EFSA: adequate water intake, 2 L a day for women and 2.5 L for men (2010)
• Directive 2009/54/EC, Annex III: the low-sodium label claim
• Thai Ministry of Public Health Notification No. 462 (2025): mineralisation of water in sealed containers
• GOST R 54316-2020: composition of Narzan and Essentuki No. 4 (table A.1)
• Icelandic Glacial: questions and answers about the water composition