Amount of water drunk and cognitive impairment

Water consumption is a nutritional habit that is often not given importance, despite being the most abundant component of the human body and essential for good physical functioning. Health organizations and dietary guidelines insist on emphasizing the need for the body to drink water, but its relationship with cognitive function has hardly been studied.

Now, a research group from the Human Nutrition Unit of the Rovira i Virgili University (URV) in Tarragona, the Pere Virgili Health Research Institute (IISPV) in Tarragona and the Network Biomedical Research Center for Physiopathology of Obesity and Nutrition (CIBEROBN), in Spain, has studied the relationship between hydration status and cognitive function in overweight or obese older adults.

The research team examined the effect of water consumption level and hydration status on changes in cognitive performance. To do this, he analyzed almost 2,000 older people who also suffered from overweight or obesity and metabolic syndrome. During two years of follow-up, they observed changes in their cognitive health from a series of neuropsychological tests and a global assessment of their general cognitive health.

Hydration status was measured by analyzing serum osmolarity, which indicates the amount of chemicals dissolved in the blood serum.

The results of the study indicated that older people with metabolic syndrome and overweight or obesity who were poorly hydrated had worsening cognitive function over time compared to those who were well hydrated. This was especially observed in males more than in females.

These results provide further insight into the potential relationship between water intake, hydration status, and cognitive health. It also highlights the need for future studies to further investigate the impact of consuming water, as well as recommendations for fluid intake and long-term hydration status to determine patterns of cognitive health.

This work has been carried out by a team that includes postdoctoral researcher Stephanie K. Nishi; Jordi Salas-Salvadó, Professor of Nutrition and Bromatology at the URV and Nancy Babio, Associate Professor at the Department of Biochemistry and Biotechnology at the URV. All three are part of the CIBEROBN and the IISPV. This study was carried out in collaboration with the PREDIMED-Plus consortium of investigators.

From left to right: Nancy Babio, Carlos Gómez Martínez, Stephanie K. Nishi, Indira Paz-Graniel and Jordi Salas-Salvadó, from the research team. (Photos: URV)

The study is titled “Water intake, hydration status and 2-year changes in cognitive performance: a prospective cohort study”. And it has been published in the academic journal BMC Medicine. (Source: URV)