MSU Health and Human Development professor Dan Heil and a team of graduate and undergraduate students conducted a study that found that individuals drinking mineral-based alkaline water, along with a water company's supplement, were better hydrated and had higher pH levels than those who consumed water without a high mineral content.
The findings suggest that certain mineralized water may impart some health benefits, Heil said.
"I was surprised at how dramatic the effect was on the body, and how quickly it reversed when (the study participants) stopped drinking the water," he added.
In the early 2010 study, the research team split 38 young adult volunteers into a control group and an experimental group.
Members of the control group drank only non-mineralized bottled water over the course of four weeks. Members of the experimental group drank alkaline water containing a naturally high mineral content, as well as a water company's supplement that is designed to stabilize pH and minerals, during the second and third weeks of the study. During the first and fourth weeks, experimental group members consumed non-mineralized bottled water in order to help measure results. The study participants received all of their water from the researchers and were not informed about which group they were in.
Throughout the study, the research team collected blood and urine samples from each individual three times each week to measure blood and urine pH and osmolality, a measurement method of mineral concentration. They also measured each participant's total daily urine volume. Study participants kept records of the food and water they consumed and maintained regular levels of exercise.
Part of why the research is important is because every chemical reaction in every part of the human body is highly sensitive to changes in both temperature and pH, Heil said. As a result, the body has tight control mechanisms in place to keep temperature and pH relatively constant. In general, pH is a measure of how acidic -- which equals a relatively low pH -- or alkaline -- which equals a relatively high pH -- a liquid or solution is. Human bodies work to maintain a fairly neutral pH, Heil said, because it is most conducive to chemical reactions that need to occur. However, diet and exercise choices, as well as certain diseases, are acidic influences, which the body must work to counter.
The researchers measured no significant changes in members of the control group, but the experimental group did show significant increases in both the blood and urine pH when they consumed highly mineralized water in the study's second and third weeks. The experimental group also showed a decreased blood and increased urine osmolality, as well as a decreased urine output during the second and third weeks of the study, which indicated higher levels of hydration. The changes measured in the experimental group reversed once its members switched back to non-mineralized water in the fourth week.
Kendra Anderson, an MSU exercise science student who participated in the study as part of the experimental group, said the results made sense to her when she reviewed the data after the study's conclusion.
"Once we started looking at the data, it clicked in my mind," she said, adding that during the second and third weeks, when she consumed the alkaline water, she drank half a liter to a full liter less of water every day.
"It makes sense, because it's more hydrating," she said. But, Anderson couldn't taste the difference in the water.
Heil noted that people participating in the study who had the largest, most consistent changes were those who drank more water. Those changes tended to appear in individuals who exercised a lot, too.
"For the average person who is fairly sedentary and drinks one to two liters of water per day, the impact is relatively small," he said.
Heil credited the MSU students - about eight graduate students and a large handful of undergraduate students - for their work on the study.
"It was great experience in research and data collection in a short period of time," Heil said.
Graduate student and research team member Eddie Davila said that the experience was valuable.
"It was good to see how an in-depth research study worked," he said. "It reinforced what I had learned in classes about research design and why things were done in a certain way... it was nice to apply and understand why things have to happen the way they do."
Heil said more research is needed. One challenge of the study was that it was funded by and designed to test only one company's mineralized water, and the results may not apply to all mineralized water. The water tested comes from a river fed by glacial run-off and contains potassium, magnesium, calcium, selenium and silica, as well as the company's supplement. Including other types of mineralized water could have made the study more universal.
However, even though a company paid for its product to be tested doesn't mean it affected the research outcomes, Heil said.
"Consumers should know that just because a company is funding research doesn't mean the results will come out in their favor," he said. "When we do research, we go in specifically with the intention that we'll find out whatever it is we'll find out."
Heil said that the take-away from the study is that water has the potential to influence one's health.
"The big picture is that consumption of water alone can possibly impart health benefits above and beyond being hydrated," Heil said. "It's an emerging part of nutrition research that many Americans aren't as aware of as in other parts of the world.
"I wouldn't say that water is more important than what you're eating, but it's a complement to what you're eating," he added.
Even though more research needs to be done, Heil said the research results were unexpected and could be significant.
"They may show something more than a performance advantage," he said. "There may actually be a health advantage.
"As consumers of water, we should all probably be a lot more curious," he added.
Dan Heil, (406) 994-6324 or firstname.lastname@example.org