The importance of education and cost incentives on individual food choices at the Harvard School of Public Health (HSHP) cafeteria

The frequency of regularly consuming meals prepared outside of the home is increasing. As these meals have been found to be of lesser nutritional quality, it is important to understand eating behavior and the determinants of food choices at the pointof-purchase.

Individual food choices are influenced by a number of factors, including taste, availability, convenience, cost, health consciousness, and body-weight considerations. In this study, the authors explored whether reducing the price of foods considered healthy in combination with the distribution of educational material about diet and health would increase the purchase of healthpromoting foods and decrease the purchase of foods considered less healthy and whether such behavior can be maintained beyond the intervention.

Description of the intervention and its assessment

Michels et al. conducted a study of consumer choice in the HSPH cafeteria, which serves the community of faculty, staff, and students and attracts customers from other Harvard University institutions. The cafeteria offers a variety of foods and they identified a list of healthy foods (salad bar, stir-fried dishes, Saluté entrée, whole-grain pizza, yogurt, and fruit) and less healthy foods (regular entrée, regular pizza, hamburger, hot dogs, French fries, cookies, cakes, and desserts). The intervention (named Nutrition Awareness weeks) consisted of

  1. reducing the price for the healthy foods and dishes by 20%, which was financed by the Dean’s office. It was announced in the school newsletter and advertised within the cafeteria;
  2. distributing educational material that included general information on healthy nutrition and lifestyle;
  3. free blood pressure reading during the first two days of the promotion (to raise awareness).

During three consecutive five-week periods, the Following assessments were made:

  • First period: baseline assessment. The servings purchased for the food items included in the project were counted.
  • Second period: intervention. The identified healthy foods and dishes were subsidized by 20%.
  • Third period: follow-up. The price returned to their initial levels.

What kinds of modifications were observed in the purchases?

The total caloric content and the number of servings of the purchases did not change significantly, but increased slightly during the intervention and follow-up periods compared with the baseline. The modifications of the sales of the individual food items and meals were as follows:

  • The consumption of stir-fried dishes increased 27% during the reduced-price period and the increase remained at 25% after prices returned to their original levels.
  • The use of the salad bar increased by 15% during the reduced-price period and climbed to 53% after the Nutritional Awareness weeks were over.
  • The consumption of regular entrées, French fries and hamburgers/cheeseburgers declined by
    43%, 20%, and 58% respectively during the promotion, and the reduction remained at 41%, 14% and 12% respectively thereafter.
  • There was, however, a 56% increase in the consumption of cakes and desserts during the nutrition promotion period; this increase remained at 59%, thereafter.

    Overall, during the intervention period, the consumption of healthy foods increased by a significant 6%, and the consumption of lesshealthy foods declined by 2%. After the prices returned to their original levels, the consumption of healthy foods increased further to a statistically significant 17% and a 2% decline in the consumption of less healthy foods persisted.

Subsidizing and promoting healthful meals result in an increase of consumption of these types of foods and a decline of the unhealthy ones

A promotional campaign with a reduction in price was associated with a modest overall increase in the consumption of healthpromoting foods and meals and a slight overall decrease in the consumption of less-healthy foods and meals. Moreover, the increase in the consumption of healthy food items increased further after the end of the cost-saving period and promotion.

Hence, Michels et al. observed an increase in the consumption of raw and cooked vegetables and a decrease in dishes rich in saturated fats. Increased consumption of healthy foods was maintained beyond the period of a reduced pricing structure. It is possible that consumers became more conscious of their choices as a consequence of the educational campaign, that the financial incentive made them try and appreciate healthier foods, and that their new-found habits were maintained beyond the subsidized period.

Consumption of cakes and desserts increased during and after the promotion. Indeed, the caloric intake and the number of servings purchased remained largely the same. It is possible that consumers respond to changes in food prices and income by adjusting their food choices to maximize their satisfaction.

In conclusion, this study indicates that subsidizing healthful meals and educating consumers about the importance of a healthy diet can result in a modest increase in the selection of healthy foods and meals that can be maintained beyond the time periods of subsidy and promotion. It underlined the importance of nutritional education for the promotion of healthy diets as tasty and inexpensive and confirmed that cost incentives are important determinants of food choices.

Journal of the American College of Nutrition, Vol. 27, No. 1, 6–11 (2008)