Life Member of Food Writers New Zealand Award: Lea is honoured to receive a Life Member of Food Writers New Zealand Award in recognition of her work as an author and nutritionist in the realm of food communications. Read more »



Diet therapy

Water intoxification!

Believe it or not there is such a state.

It is more commonly known as Hyponatraemia, and occurs when the concentration of sodium in the blood is lower than normal (<136 mEq/L).

Sodium is essential in nerve and muscle function and also helps to maintain blood pressure.

Symptoms of hyponatraemia

Symptoms range from confusion, lethargy, nausea and muscle twitches, which can progress to seizures and in severe cases results in coma or death.

It develops most commonly in less competitive athletes taking part in endurance exercise events lasting at least 5 hours, who maintain high rates of fluid intake. However it may also occur in people whose kidneys do not function properly, those with heart failure, cirrhosis of the liver and Addison’s Disease.

Preventative measures

It appears that symptomatic hyponatraemia can only develop with gross fluid overload. To prevent this occurrence, susceptible athletes should moderate their fluid intake during exercise to ensure they do not risk developing fluid overload. It has been recommended that intakes of approx 500ml per hour should cover the requirements of nearly all athletes, of a less competitive nature, undertaking prolonged exercise.

When continuous exercise extends beyond 90 minutes it is also advisable to utilize a sodium-containing beverage such as a sports drink to replace any sodium losses.

To help determine your fluid requirements contact Lea in the early stages of your training if possible so that you have time to develop, and test, your hydration plan well before any serious competition.

About the author View all

Lea Stening

Lea is one of New Zealand’s leading paediatric dietitians and also specialises in Sports Nutrition. She has specialised in Paediatric Nutrition for 31 years and in 1985 was the first paediatric dietitian to enter private practice in New Zealand. Lea helps families through her private consultations, public lectures, newspaper and magazine articles as well as television and radio interviews. Read more »

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