Hydration in the local climate: how much and what to drink

Stockholm registered its driest June in 14 years this summer, with total rainfall across the city falling to just 28 millimetres — less than half the monthly average of 59 millimetres recorded by SMHI, the Swedish Meteorological and Hydrological Institute. On Södermalm and in Östermalm, residents have been spending long hours outdoors in 24-degree heat without the humidity cues that normally signal thirst. The result, nutritionists and general practitioners say, is a quiet epidemic of under-hydration that rarely makes the news but quietly undermines energy, concentration and cardiovascular performance.

The timing matters. July is peak outdoor season in the Swedish capital. Djurgården fills with cyclists and runners from dawn. The kayak rental queues on Strandvägen stretch past the Grand Hôtel by 9 a.m. on weekdays. Yet the cool Baltic breeze that makes Stockholmers feel comfortable also suppresses sweat perception, meaning the body loses moisture without triggering the usual alarm signals. Public health messaging around hydration tends to spike when temperatures exceed 30 degrees Celsius — thresholds Stockholm rarely hits — so moderate but sustained heat rarely gets the attention it deserves.

What the research actually says

The European Food Safety Authority recommends 2.0 litres of total water intake daily for adult women and 2.5 litres for adult men — figures that account for water in food, not just drinks. Physically active adults exercising for more than an hour, as many Stockholmers do during summer, should add roughly 500 to 750 millilitres per hour of moderate exercise. Those numbers come from EFSA's 2010 dietary reference values, which remain the benchmark used by Swedish Livsmedelsverket, the National Food Agency, in its public guidance.

Stockholm's tap water is consistently ranked among the cleanest in Europe. Stockholm Vatten och Avfall, the municipal water utility, draws from Lake Mälaren and reports average hardness levels around 4 degrees dH — soft enough that no filtration jug is necessary. A litre from the tap costs fractions of a single öre to produce. By contrast, a 500 ml bottle of Ramlösa mineral water at a Hemköp on Götgatan currently retails for around 12 kronor, meaning a household relying solely on bottled water would spend close to 200 kronor a month more than necessary. The environmental cost adds up too: Stockholms stad's own climate action plan, updated in 2024, targets a 30 percent reduction in single-use plastic by 2028.

Electrolytes complicate the picture. Sweat contains sodium, potassium and magnesium, and replacing water alone after heavy exertion can dilute blood sodium levels — a condition called hyponatraemia that presents initially as fatigue and headache. Nutritionists affiliated with Capio Vårdcentral Liljeholmen suggest that anyone exercising outdoors for more than 90 minutes should consider a small salty snack — a few crackers, a handful of salted nuts — alongside their water intake rather than reaching for commercial sports drinks, which typically carry 6 to 8 grams of sugar per 100 ml.

Practical guidance for Stockholm's climate

Coffee deserves a specific mention in any Swedish hydration conversation. Stockholm has one of the highest per-capita coffee consumption rates in the world — Swedes drink roughly 8.2 kilograms of coffee per person per year, according to the International Coffee Organization's 2025 data. Moderate coffee consumption, up to four cups daily, does not cause net fluid loss, a point that the Livsmedelsverket confirmed in updated guidance published in March 2026. Fika culture, in other words, is not a hydration problem.

Herbal infusions served cold — particularly elderflower, which is widely available at Östermalmshallen and at the weekend markets in Hötorget — offer a practical middle path: flavour without caffeine, sugar or plastic waste. Infusing a litre of cold water with fresh mint and cucumber overnight costs almost nothing and eliminates the boredom that causes many people to drink less than they should.

The simplest benchmark remains urine colour. Pale straw yellow signals adequate hydration. Dark amber signals a deficit. Checking before a morning run on Långholmen or a lunchtime swim at Eriksdalsbadet takes two seconds and costs nothing. On dry July days in Stockholm, that check is worth making a habit.

For personalised advice on hydration and nutrition, speak with your local vårdcentral or a registered dietitian.