Overview
- The Met Office has issued a rare red heat warning this week as temperatures climbed into the high 30s across parts of the UK, prompting fresh public‑health messaging.
- The UK Health Security Agency says people should aim for about six to eight cups of fluid daily but cautions that drinking too much can dilute blood electrolytes and cause hyponatraemia.
- NHS guidance lists eight specific dehydration signs in babies and children to watch for, including fewer wet nappies, no tears, a sunken soft spot or eyes, dry mouth, irritability or drowsiness, rapid breathing or heartbeat, and cold hands or feet.
- Clinicians and a sports nutritionist warn adult dehydration can be subtle—symptoms include headache, poor concentration, cravings and persistent bad breath—and advised that fluid needs rise in hot conditions to around three litres when active.
- Practical advice includes checking for pale‑straw urine as a hydration cue, counting water plus lower‑fat milk and sugar‑free drinks toward intake, avoiding high‑sugar drinks, limiting caffeine to about 200 mg a day, and giving extra attention to infants, older adults, pregnant or breastfeeding people and those who are ill or highly active.