Don't Drink Coffee When You're Tired: A Nutritionist Explains

Dr Diana Felicia Suganda, a clinical nutrition specialist (M.Kes), urged the public not to consume coffee in excess when the body is fatigued. Rather than delivering sustained energy, caffeine in coffee risks accelerating dehydration and flushing out important minerals from the body.

According to Diana, coffee has diuretic properties that stimulate the kidneys to produce more urine. This process causes sodium and other electrolytes essential for maintaining focus and stamina to be flushed away.

‘In fact, drinking coffee tends to give us a short-lived stimulant effect when we are tired,’ she said, quoted by Antara on Tuesday (19 May).

She explained that the increased urine output will hasten dehydration. After all, when tired, the body greatly needs fluid and electrolyte balance — such as sodium, potassium, calcium, and magnesium — to support muscle function and the nervous system.

As an alternative, Diana advised the public, particularly those who are active in sport, to opt for fluids containing electrolytes to restore energy and stave off fatigue. Electrolytes play a vital role in regulating blood pressure and supporting heart function.

However, coffee consumption is not banned entirely. ‘If you do need coffee as a pre-workout, go ahead. But make sure you rehydrate with fluids. Adequate fluids, adequate electrolytes too,’ she added.

She also reminded that fluid needs vary between individuals and should be adjusted to body weight, given that around 60 to 65 percent of the human body’s composition is water.