A study looking at food costs and weight loss is published ahead of print in the Journal of Epidemiology and Community Health. It suggests that while Mediterranean diets may be healthier, they are also costly. This may dissuade some people.

In 2008, the dietary patterns of over 11,000 Spanish university graduates were evaluated by researchers.

All the participants were already part of the long term SUN study, which began in 1999. It examined the connection between diet and the incidence of obesity and long term conditions. It was based on questionnaire responses every two years.

With the help of food frequency questionnaires, the researchers evaluated dietary habits. They listed 136 food items, grouped into 30 categories. The daily portions were measured in grams. Using nationally available data, the costs of foods were then calculated.

They then used a validated scoring system to identify whether consumption fell predominantly into two categories:

• Mediterranean diet: fish, olive oil, legumes, fruit and vegetables
• Western diet: high fat, sugar, red meat content

Findings indicated that a higher Mediterranean diet score was linked with considerably higher daily costs. A higher Western diet score was associated with significantly lower daily costs.

With higher Western diet scores, less money was spent every day on food.

Higher food spending was associated with eating less in general, consuming fewer energy dense foods, and snacking less between meals, than those who spent less.

Around a third (31 percent) of participants recorded a weight gain of just over half a kilo every year. After adjusting for factors that could possibly influence the results, those who spent the most on food were 20 percent more likely put on weight. This was irrespectively of which dietary pattern they had.

“Those who spent more tended to be older, were more likely to be former smokers, and generally weighed more to begin with”, explain the authors, “which might mean they were more prone to weight gain because of other lifestyle or genetic factors,” they suggest.

They also tended to drink more fruit juice, soft drinks, and alcohol, all of which are loaded with calories.

The authors say that the evidence in favour of the health benefits of a Mediterranean diet has been gradually accumulating. At the same time, the adverse effects of a Western diet on health are not in dispute.

“But it may be helpful to tax unhealthy foods and subsidise healthier options,” they suggest, “because the high cost of a Mediterranean diet may put some people off.”

“Costs of Mediterranean and western dietary patterns in a Spanish cohort and their relationship with prospective weight change”
C N Lopez, M A Martinez-Gonzalez, A Sanchez-Villegas, A Alonso, A M Pimenta, M Bes-Rastrollo
Online First J Epidemiol Community Health 2009
doi 10.1136/jech.2008.081208
Journal of Epidemiology and Community Health

Written by Stephanie Brunner (B.A.)