Sodium

Sodium is an electrolyte. MedlinePlus says it helps control the amount of fluid in your body. It also helps your nerves and muscles work properly. Sweat contains sodium, so a long shift in the heat can lower it.

Too little sodium in the blood is called hyponatremia. It can follow heavy sweating combined with drinking only plain water for hours. Crews should know the risk. NIOSH also tells workers with heat cramps to avoid salt tablets. The label on Rapid Restoration Drops lists sodium (seawater) at 200 mg per 1 tsp serving. See electrolytes 101 and the hyponatremia guide.