Study: High-Protein Dieters Need to Drink Extra Water to Combat Dehydration

High protein weight-loss regimens like the Atkins diet can lead to dehydration, according to researchers at the University of Connecticut Department of Nutritional Sciences.

The more protein dieters eat, the more water they need to drink whether they feel thirsty or not, the researchers cautioned..

Five UConn student athletes consumed low, moderate and high amounts of protein for four weeks each. The low amount of protein was equal to the recommended daily allowance set by the U.S. Department of Agriculture. The moderate protein diet included more than two times the recommended protein intake, an amount typical for the general population. The high protein diet used four times the recommended level. The hydration status of the students was evaluated twice each week.

"We found that certain hydration indices tended to be influenced as the amount of protein in their diets increased," said Nancy Rodriguez, lead investigator of the study presented at the 11th annual Experimental Biology meeting in New Orleans.

When the athletes ate the highest amounts of protein, their blood urea nitrogen measured in the abnormal range, an indication of compromised kidney function. The value returned to normal after the amount of protein being eaten was reduced. Other tests showed that the high protein diet caused the kidneys to produce more concentrated urine.

"Based on our findings, we believe that it is important for athletes and non-athletes alike to increase fluid intake when consuming a high protein diet, whether they feel thirsty or not because our study subjects said they did not feel a difference in thirst from one diet to the next," said Rodriguez.

People who eat high protein diets should increase their fluid intake and avoid excessive amounts of caffeine or any other agent that acts as a diuretic, warned Rodriguez.

Other sources: University of Connecticut