Swapping sugary drinks for diet drinks worked no better than swapping them for water
Who it’s about: Adults
- No differenceGoals
Swapping sugary drinks for diet drinks cut sugary drinks no more than swapping them for water.
- Action: Replace the habit with another activitytested
- Action: Make an if-then plan for your obstacleused
- Rule: Put a visible cue where you'll do itused
- Rule: Get a reminderused
Randomised trial of 136 adults who drink a lot of sugary drinks · vs people who swapped to water instead · they rated themselves · ⚠ only counted people who finished; numbers unreliable; uneven outlier exclusions between groups
- No differenceHabits
Sugary drinks felt no less automatic after a swap to diet drinks than after a swap to water.
- Action: Replace the habit with another activitytested
- Action: Make an if-then plan for your obstacleused
- Rule: Put a visible cue where you'll do itused
- Rule: Get a reminderused
Randomised trial of 136 adults who drink a lot of sugary drinks · vs people who swapped to water instead · they rated themselves · ⚠ only counted people who finished; numbers unreliable; uneven outlier exclusions between groups
The study
Who took part
136 adults who saw themselves as frequent sugary-drink drinkers, out of 184 who started. They were about 31 on average, about half were women, and most lived in the UK or the US.
What they did
Everyone wrote up to three if-then plans to swap their usual sugary drink for another drink. They kept the plans where they could see them and got a weekly reminder email for two months. One group swapped to water and the other to diet drinks.
What happened
After two months, both groups drank far fewer sugary drinks: about 4 a week, down from 12. The drop was the same in both groups. With no group that made no plans, we can't tell what caused the drop. The paper's numbers don't always match, and more people were left out of the diet-drink group.
Source
A Habit-Based Randomised Controlled Trial to Reduce Sugar-Sweetened Beverage Consumption: the Impact of the Substituted Beverage on Behaviour and Habit Strength (2020)
DOI: 10.1007/s12529-020-09906-4 (opens in a new tab)Tools in this study
Action3
Replace the habit with another activityPick a substitute activity to do in place of the habit you want to cut.
Action4
Make an if-then plan for your obstacleImplementation intentions or WOOP/MCII: if this obstacle happens, then I will do that.
Rule · where5
Put a visible cue where you'll do itA sticker, poster, object or wearable prompt at the point of action.
