BACKGROUND: The Mediterranean dietary pattern might be a potential tool for the prevention of obesity. OBJECTIVES: We studied the association between adherence to 6 previously published scores used to assess the adherence to the Mediterranean diet and weight change. We also assessed the risk of relevant weight gain (≥ 5 kg) or the risk of developing overweight or obesity. DESIGN: The study population included 10,376 Spanish men and women who were university graduates (mean age = 38 y) and were followed up for a mean (± SD) of 5.7 ± 2.2 y. Diet was assessed at baseline with a 136-item, previously validated food-frequency questionnaire. Weight was assessed at baseline and biennially during follow-up. RESULTS: Participants with the lowest adherence (≤ 3 points) to the Mediterranean dietary score (MDS) proposed by Trichopoulou et al (range: 0-9; N Engl J Med 2003;348:2599-608) exhibited the highest average yearly weight gain, whereas participants with the highest (≥ 6 points) adherence exhibited the lowest weight gain (adjusted difference: -0.059 kg/y; 95% CI: -0.111, -0.008 kg/y; P for trend = 0.02). This inverse association was extended to other a priori-defined MDSs. The group with the highest adherence to the MDS also showed the lowest risk of relevant weight gain (≥ 5 kg) during the first 4 y of follow-up (odds ratio: 0.76; 95% CI: 0.64, 0.90). CONCLUSIONS: Adherence to the Mediterranean dietary pattern is significantly associated with reduced weight gain. This dietary pattern can be recommended to slow down age-related weight gain.