High Protein Diets Can Lead to Dehydration
(Released: April 22, 2002)
By Janice Palmer, Office of University Communications
STORRS, Conn. -- The more protein you eat the more water you
should drink, according to a study by the University of
Connecticut's Department of Nutritional Sciences. The research
is being presented today at the 11th annual Experimental Biology
meeting in New Orleans.
As part of the study, five UConn student athletes who are
runners consumed low, moderate and high amounts of protein for four
weeks at a time. Their meals were carefully planned and scrutinized
by Nancy Rodriguez, the lead investigator, who worked with
University Catering Services to provide the meals. The hydration
status of the athletes was evaluated bi-weekly.
"We found that certain hydration indices tended to be
influenced as the amount of protein in their diets increased,"
says Rodriguez, an associate professor in nutritional sciences, she
also holds joint appointments in kinesiology and allied health.
When the athletes consumed the highest amounts of protein, their
blood urea nitrogen (one of several clinical laboratory tests used
in evaluating kidney function) reached abnormal ranges. This value
returned to normal when protein intake was reduced. Other tests
indicated that the high protein diet caused the kidneys to produce
more concentrated urine.
The recommended daily protein intake for the average person is
set by the U.S. Department of Agriculture and it is dependent on
body weight. The recommended daily allowance (RDA) for an
individual weighing 150 pounds is 70 grams of protein, which can be
easily obtained in a diet including two glasses of milk, three to
four ounces of chicken, and a bowl of cereal, rice or pasta. In
this study, the low protein diet nearly equaled the RDA. The
moderate diet included more than two times the recommended protein
intake (which is typical of the general population), and the high
protein diet incorporated a little more than four times the
"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," says Rodriguez. She
received funding for this study from National Cattlemen's Beef
Association and the University of Connecticut's Research
For most people, just a two percent decrease in body fluid can
negatively affect performance and cardiovascular function. Keeping
in mind that the average adult should be drinking eight to 10
glasses of water each day, Rodriguez recommends that those who are
exercising and/or eating high amounts of protein increase their
fluid intake and avoid excessive amounts of caffeine or any other
agent that acts as a diuretic.
For this study, Rodriguez and her team worked closely with Carl
Maresh and Larry Armstrong, professors of kinesiology at UConn who
are experts in the fields of thermoregulation and human
performance. William Martin, a second-year nutritional sciences
graduate student studying with Rodriguez, will present their
findings at the conference, where more than 14,000 biomedical
researchers are gathered.
April 2002 Releases
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