Water supplementation lowers copeptin, plasma glucose in adults with high copeptin
Water supplementation in individuals with habitually low water consumption and high levels of copeptin is a safe and effective intervention in reducing copeptin, suggests a recent study, adding that this may help lower fasting plasma glucose and reduce the risk of diabetes.
There was an increase in reported mean water intake from 0.43 to 1.35 L · d−1 (p<0.001), without any observed changes in diet.
Median urine osmolality decreased from 879 (interquartile range [IQR], 705-996) to 384 (IQR, 319–502) mOsm · kg−1 (p<0.001), while urine volume increased from 1.06 (IQR, 0.90–1.20) to 2.27 (IQR, 1.52–2.67) L · d−1 (p<0.001) and baseline copeptin decreased from 12.9 (IQR, 7.4–21.9) to 7.8 (IQR, 4.6–11.3) pmol · L−1 (p<0.001).
Water supplementation led to lower fasting plasma glucose from a mean of 5.94 (SD, 0.44) to 5.74 (SD, 0.51; p=0.04). Participants in the top tertile of baseline copeptin showed the most significant water-related reduction of both fasting copeptin and glucose concentration in plasma.
“Further investigations are warranted to support these findings,” the authors said.
This study included 31 healthy adults with high copeptin (>10.7 pmol · L−1 in men and >6.1 pmol · L−1 in women) identified in a population-based survey conducted from 2013 to 2015 and with a current 24-hour urine osmolality of >600 mOsm · kg−1.
Participants had an addition of 1.5 L water daily on top of habitual fluid intake for 6 weeks. Pre- and postintervention fasting plasma copeptin concentrations were the main outcome measures.
Copeptin is a marker of vasopressin and associated with low water intake and high diabetes risk, according to the authors.