Undergraduate Research at Virginia Tech

Can Beverage Consumption Really Affect Weight?

By Alyssa Haak, sophomore English major

Over summer 2007, Human Nutrition, Foods, and Exercise (HNFE) junior Kelly Wilson took up the task of researching beverage consumption patterns in middle-aged and older adults, a segment of the population who is particularly prone to weight gain.

Epidemiological studies have shown that beverage consumption in the United States has increased in the past decade, along with the increasing rates of obesity. Meanwhile, older adults are prone to dehydration due to limited water consumption. Wilson and other HNFE Summer Scholars, colleagues at the Human Integrative Physiology Laboratory, assistant professor Brenda Davy, and associate professor Kevin Davy began research on “Habitual Beverage Consumption Patterns in Older Overweight and Obese Adults.” The researchers are particularly interested in the types of beverages the research subjects consumed, the calorie content of the beverages, and how these may relate to their body weight status.

For Wilson, the process began when her mentor, Christina McIntyre, associate director of the University Honors program, encouraged Wilson to apply to become one of five scholars in the first HNFE Summer Scholars research program. Once the scholars were selected, McIntyre and associate professor Deborah Good looked at the participants’ majors and interests in order to place them with the most compatible professors. Since Ms. Wilson is a HNFE major with minors in both chemistry and psychology, she was matched up with Brenda and Kevin Davy at the Human Integrative and Physiology Laboratory.

She was also lucky enough to watch and learn from a Basal Metabolic Rate test, which measures the number of calories your metabolism burns daily if no activity is introduced. And she observed a Dual Energy X-Ray Absorptiometry scan, (shown in the image at right) which looks at body composition, and a Baroreflex Sensitivity/Muscle Sympathetic Nervous System Activity test.

For the beverage consumption research, Wilson and the team had older overweight, and obese adults record their food and beverage intake for four consecutive days. The records were then analyzed; first by software that documented their energy (calorie) intake from the food and then manually to determine the intake of water, juices, coffee, tea, soft drinks, diet drinks, milk, and alcoholic beverages.

Recommended water intake is three to six cups a day; however, this population of overweight middle-aged and older adults drank only about one cup of water a day. The research subjects were divided into “water consumers” and “non-water consumers” based on the amount of water each consumed. In the end, it was observed that the “water consumers” had a lower Body Mass Index (BMI), than the “non-water consumers.” (BMI is an assessment of whether an individual is underweight, normal weight, or overweight.) It was also evident that the “water consumers” took in fewer calories (deleted ‘less energy’) from beverages. However, the differences were not statistically significant enough to be absolutely conclusive, possibly because of the small sample size and limited BMI range.

Wilson learned an incredible amount from her work, observations, and surroundings. She jokes that “The biggest lessons I learned from the summer, ironically, were about research and about myself. I learned I was too impatient and too much of a perfectionist. To work with humans requires a lot of patience. And to work in research means that nothing will seem to go correctly… But when things just got more and more complicated, I just had to laugh. Things work out eventually. And thus is the nature of the beast!”

Once she got into the research mindset, Wilson was able to observe and learn some very interesting things about her research: There seemed to be a trend related to beverage consumption and BMI. However, as stated above, the research results were not statistically significant. She also learned that this population consumed far less water than was recommended, which is consistent with the suggestions of a decline in the natural thirst mechanism with advancing age. This may indicate that health professionals should encourage middle aged and older adults to drink ample amounts of water each day.

Future analyses include the addition of a comparison group of non-obese middle aged and older adults, which could lead to the development of weight loss interventions targeted at habitual beverage consumption patterns in middle aged and older adults.

Wilson has received a Fralin Obesity/Nutrition Undergraduate Research Fellowship. As a fellow she will continue to help with biopsies for the same research project with a larger group of older adults and more variance in BMI.

She plans to become a physical therapist and hopes that this research will help prepare her for research into new exercises and discoveries that could be used to help her future patients. In the meantime, she has made some ever-lasting memories. Talking to other scientists in her field, the friendships and relationships formed through the HNFE Summer Research family, and the socials at bowling alleys and the Davys' home were unforgettable experiences.

Wilson’s suggestion for others considering this program or research in general is “DO IT. Just do it. It’s worth it.”