The Smart Water Bottle Experiment
Drinking water is essential to human health. The amount one should drink varies from person to person based on gender, age, height, weight, physical activity, sweat levels, metabolism level, body temperature, humidity levels, external temperature, altitude, quantity and quality of food intake, quantity and quality of other fluids’ intake and host of other details. When you don’t get enough water, every cell of your body is affected. You lose a lot of electrolytes, including sodium, potassium and chloride, which are essential to your body’s functions. Pretty much all of your cellular communications revolve around sodium and potassium, including muscle contractions and action potentials. Fatigue, lethargy, headaches, inability to focus, dizziness and lack of strength are all signs of dehydration. Nature has given us a powerful alert system – thirst. But in our busy chaotic lives we often ignore it and forget to drink water.
Behavioural Design vs awareness
There is enough information about why we should drink more water, yet most people feel they don’t drink enough. Education doesn’t change behaviour.
Behavioural change requires a different approach. Drinking water regularly is a good habit. Habits are essentially automatic in nature, where one does not consciously think about the action. In other words, habits are auto-pilot behaviours. For a behaviour to become a habit, it requires three things to come together – trigger, action and reward. When the loop gets completed, the habit sets into place. For example, over a period of time we have gotten used to waking up in the morning (trigger), brushing our teeth (action) and feeling fresh (reward). To create good habits, initially conscious effort is required. However, we humans are lazy, so the lesser the effort to get the habit started, the better. Eg. We forget to drink water during the day. So if there’s a trigger like a reminder from the water bottle, we’re likely to drink water. Over time the action of opening the water bottle because of the reminder can become auto-pilot i.e. become a habit. This approach led us to create a water bottle that glowed and beeped that gently nudged people to drink water 16% more.
We chose to do an experiment in an office of one of our corporate clients. The administration department of that company would keep filled-water-bottles on the desk of each employee every morning and refill it once every evening. So we bought the same type of water bottles for our experiment so as to not draw any suspicion amongst participants. And we created two versions of caps. In the first version of the cap, we fitted a chip which recorded the number of times the water bottle was opened. In the second version of the cap, we fitted a chip which recorded the number of times the water bottle was opened and in addition, the cap now glowed and beeped once after every two hours of the water bottle being opened. If the bottle wasn’t opened, then the cap would glow and beep after an hour. When the water bottle was opened, the cap would sense it and stop glowing. In both versions the chip was hidden inside the caps.
Creating prototypes of both versions of water bottle caps took longer and was costlier than we expected (planning fallacy). We could only produce a total of 70 water bottle caps over more than a year. Thirty-five pieces of each version – first version with recording chip without glow and beep and second version with recording chip with glow and beep. Because of being able to produce 70 water bottle caps we chose to randomly select thirty-five participants from the office employees who wished to participate in our experiment.
In week 1 we gave them our similar looking water bottles with the first version of the cap with recording chip hidden in it. In week 2 we replaced the caps with the second version of the cap with the recording chip with the glow and beep. We accounted for data from Monday morning to Friday night in both weeks. We then compared the data of how many times the water bottle was opened with the numbers of hours the employees had spent in office on each day of Week 1 (no glow and beep) and Week 2 (glow and beep). Had we been able to conduct the experiment amongst a larger set of sample, we would have chosen the typical control group and treatment group, but due to the above mentioned capacity, time and money constraints we did a before-and-after format for this experiment.
In week 2 employees opened the water bottles 16% more than in week 1. It means the employees were not sufficiently hydrated with regular water bottles even though they were kept on their desk right in front of their eyes. The simple Behavioural Design of glow and beep water bottle caps got employees to drink 16% more frequently than without the Behavioural Design nudge.
Frequently asked questions
Q. How much water does one need?
A. Scientific studies are inconclusive on the amount of water required by an adult. Some say its 3 litres. Some say 2.5 litres. Some (Mayo clinic) say for men its 3 litres and for women its 2.2 litres. But fact is that calculating how much water you need depends upon your gender, age, height, weight, physical activity, sweat levels, metabolism level, body temperature, humidity levels, temperature, altitude, quantity and quality of food intake, quantity and quality of other fluids intake and host of other reasons. It’s extremely difficult to calculate real time hydration levels accurately.
Q. Why didn’t we create a bottle that could calculate how much water each individual person needed?
A. To do that we’d need to know people’s gender, age, height, weight, physical activity, sweat levels, metabolism level, body temperature, humidity levels, temperature, altitude, quantity and quality of food intake, quantity and quality of other fluids intake and host of other details. It’s extremely difficult to calculate real time hydration levels accurately. Sensors and software that can capture all of the above seamlessly are very expensive as of date. Measuring only some of the inputs would lead to an inaccurate result that would be misleading. So we used a simple rule of thumb of drinking water every two hours to stay hydrated.
Q. What’s the best way to judge whether you are hydrated or dehydrated?
A. The most scientific and simplest way to judge whether you are hydrated or dehydrated is to look at the colour of your urine. If your urine is crystal clear it means you’re probably drinking too much water. If its light or mild yellow it means your drinking an adequate amount of water. If its proper yellow or darker it means you need to drink more water. If its brown you need to visit a doctor.
Mild Dehydration Affects Mood in Healthy Young Women – Lawrence E. Armstrong, Matthew S. Ganio, Douglas J. Casa, Elaine C. Lee, Brendon P. McDermott, Jennifer F. Klau, Liliana Jimenez, Laurent Le Bellego, Emmanuel Chevillotte and Harris R. Lieberman – The Journal of Nutrition – 21 December, 2011.
Mild dehydration impairs cognitive performance and mood of men – Matthew S. Ganioa, Lawrence E. Armstronga, Douglas J. Casaa, Brendon P. McDermotta, Elaine C. Lee, Linda M. Yamamotoa, Stefania Marzano, Rebecca M. Lopez, Liliana Jimenez, Laurent Le Bellego, Emmanuel Chevillotte and Harris R. Lieberman – British Journal of Nutrition – Volume 106 / Issue 10 / November 2011, pp 1535-1543
Lawrence E. Armstrong – an international expert on hydration who has conducted research in the field for more than 20 years (professor of physiology in UConn’s Department of Kinesiology in the Neag School of Education)