Hydration & Electrolytes

•Observational— ARIC + animal model data on chronic hypohydration

What the recent research adds

The 2023 ARIC analysis (Dmitrieva et al.) showed that middle-aged adults with serum sodium in the higher-normal range (>142 mmol/L) had accelerated biological aging and ~64% higher chronic-disease risk over 25 years. Higher water intake to keep serum sodium in 138–142 may be beneficial — the first robust human data linking hypohydration to aging biology.

Electrolytes that matter

• Sodium: 3–5 g/day reasonable for most; restrict in salt-sensitive hypertension and CHF. Indiscriminate ultra-low intake associates with worse outcomes in some cohorts.
• Potassium: most adults under-consume. Aim 3,500–4,700 mg/day from food (vegetables, fruit, legumes). Caution with K-sparing diuretics and CKD.
• Magnesium: see magnesium intervention page.
• Calcium: 1,000–1,200 mg/day from food preferred; supplements only if intake insufficient (and pair with K2/D).

When to think about it

• Endurance training in heat.
• Older adults (blunted thirst response).
• Travel / air travel.
• Diabetics with high glucose load.
• Heavy coffee or alcohol use.
• Recovery from acute illness with GI losses.

Related entries

Magnesium, Sodium controversy, Blood pressure.