When Water Becomes Dangerous: The Hidden Risk of Overhydration

Water is essential for survival and good health, but consuming excessive amounts, particularly within a short period, can sometimes disrupt the body’s fluid balance.

In Ghana, where high temperatures and outdoor activities are common, adequate hydration is important. Farmers, construction workers, athletes and other outdoor workers may lose considerable amounts of water and electrolytes through sweating during prolonged physical activity or heat exposure.

However, excessive water consumption can contribute to hyponatremia, often called water intoxication when caused by excessive water intake. This occurs when there is too much water relative to sodium in the body, causing the sodium concentration in the blood to fall.

Sodium is essential for maintaining fluid balance and normal nerve and muscle function. When sodium levels fall significantly, water moves into cells, causing them to swell. Swelling of brain cells can interfere with normal neurological function and, in severe cases, become life-threatening.

Early symptoms may include headache, nausea, vomiting, unusual tiredness and confusion. Because these symptoms can resemble dehydration or heat-related illness, feeling unwell during prolonged activity does not necessarily mean that more water is needed.

The risk is not simply about how much water is consumed in a day. It is particularly associated with fluid intake exceeding the body’s ability to remove excess water and maintain an appropriate water-to-sodium balance.

Prolonged exercise and heat exposure can increase the risk. Sweating causes losses of both water and electrolytes, including sodium. However, sweating itself does not automatically cause hyponatremia. Excessive consumption of plain water during prolonged activity can instead contribute to dangerously low blood sodium, particularly when intake exceeds fluid losses and the kidneys’ ability to eliminate excess water.

Prevention does not mean avoiding water or becoming dehydrated. Drinking according to thirst and avoiding excessive fluid consumption during prolonged activity can help reduce the risk. Urine colour may provide a general indication of hydration, although it is not a precise measure of individual fluid needs.

Water supports circulation, digestion, temperature regulation and essential cellular processes. Its benefits, however, depend on balance.

Healthy hydration is not about drinking as much water as possible. It is about giving the body what it needs and maintaining the right balance of water and electrolytes.

References
Hew-Butler, T., Rosner, M. H., Fowkes-Godek, S., Dugas, J. P., Hoffman, M. D., Lewis, D. P., Maughan, R. J., Miller, K. C., Montain, S. J., Rehrer, N. J., Roberts, W. O., Rogers, I. R., Siegel, A. J., Stuempfle, K. J., Winger, J. M., & Verbalis, J. G. (2015). Statement of the Third International Exercise-Associated Hyponatremia Consensus Development Conference, Carlsbad, California, 2015. Clinical Journal of Sport Medicine, 25(4), 303–320. https://doi.org/10.1097/JSM.0000000000000221⁠

PubMed +1
Hew-Butler, T., Loi, V., Pani, A., & Rosner, M. H. (2017). Exercise-associated hyponatremia: 2017 update. Frontiers in Medicine, 4, Article 21. https://doi.org/10.3389/fmed.2017.00021⁠