While there is widespread agreement that people need lots of fruits and vegetables in their diets, most people fall well short of meeting daily recommendations. Studies show that people of lower socioeconomic status get the least amount of fruits and vegetables, leading many public health officials to speculate that making these foods cheaper would help people add more of them to their diets.
However, to do date, there is not much good quality research examining if lowering fruit and veggie prices actually leads to increased purchasing and consumption of these foods. Recently, researchers from VU University Amsterdam carried out a well-designed trial, putting this very strategy to the test.
Their study was a randomized controlled trial. It took place in two C1000 supermarkets and two PLUS supermarkets, both chain supermarkets in the Netherlands. About 200 participants were randomized into four groups:
- A pricing discount group. Participants in this group were mailed 50% off coupons on a total of 12 fruits and vegetables every two weeks for the duration of the trial.
- A nutrition education group. Participants in this group received recipe books that used lots of fruits and vegetables. Participants also received 4 telephone calls for the duration of the trial, each session focused on nutrition and improving fruit and veggie consumption.
- A pricing discount and nutrition education group. This group received both of the above interventions.
- A control group that received no interventions.
The trial lasted for 6 months and the researchers measured how many total grams of fruit and vegetables were being purchased by participants at baseline, 1 month, 3 months and 6 months. They also measured how much their participants were spending on other types of foods.
Here’s what they found:
After 6 months, those in the discount groups purchased 5.3 kg more fruit and veggies than the non-discount groups over a 2 week period. This was statistically significant. The education-only group did not have the same kind of effect over the control group.
The number of participants who consumed sufficient amounts of fruit and veggies increased significantly from 42.5% to 61.3% after the 6 month trial in the discount groups. Those in the education-only and control group saw no improvement, shifting from 52.7% to 52.5%.
Neither discount group increased the total amount of money spent on groceries throughout the trial, indicating that the increased fruit and veggie purchases were replacing other purchases, rather than adding to.
The researchers concluded:
Our study showed that discount coupons offering a 50% price discount on fruit and vegetables led to a substantial increase in fruit and vegetable purchases.
Furthermore they recommended
We would recommend focusing on pricing strategies when designing future interventions or policy.
Waterlander WE, de Boer MR, Schuit AJ, Seidell JC, and Steenhuis IHM. Price discounts signiﬁcantly enhance fruit and vegetable purchases when combined with nutrition education: a randomized controlled supermarket trial. American Journal of Clincial Nutrition, April 2013.