LIVERPOOL, UK, SANA – People who fail to drink enough water each day may experience stronger biological responses to stress, according to a new study led by Liverpool John Moores University (LJMU).
Researchers found that individuals with low fluid intake released significantly higher levels of cortisol, the body’s primary stress hormone, during stress tests compared with those who met daily hydration guidelines — even though both groups reported similar feelings of anxiety and thirst.
The study involved 32 adults: half consumed less than 1.5 liters of water a day, while the other half regularly met the European Food Safety Authority (EFSA) guidelines of 2.5 liters for men and 2 liters for women. Saliva samples collected before and after stress tests showed elevated cortisol in the low-hydration group.
“Both groups felt equally anxious and showed similar increases in heart rate,” explained Professor Walsh, lead researcher. “But those who were poorly hydrated had much greater cortisol responses. Exaggerated cortisol reactivity is linked to higher risks of heart disease, diabetes, and depression.”
Researchers suggest that keeping a water bottle nearby — especially during stressful situations such as deadlines or public speaking — could help protect long-term health.
The findings, published in the Journal of Applied Physiology, highlight the potential benefits of meeting hydration guidelines, particularly in managing daily “micro stressors” like traffic or workplace pressures. Further studies will explore whether increasing water intake can reduce stress responses in habitual low drinkers.
Khadega / BA
