Yes, I believe a Mediterranean diet can contribute to one's happiness and overall well being. A Mediterranean diet is well rounded, doesn't have too much red meat, lots of omega 3 fatty acids in their olive oil and nuts, in addition to fish, which is a lean protein. Eating a diet as such could increase one's overall happiness and well-being.
I think a Mediterranean diet contributes to happiness. Mediterranean diets are considered to be among the healthiest of diets in current times. Mediterranean diets are attributed to providing a healthy lifestyle and a lean body for those that follow them. Being healthy and thin can dramatcially improve your state of happiness.
I do not think that a Mediterranean diet contributes to happiness. I think that any diet can contribute to happiness. But it usually depends on their person. I do however think the results that come from a Mediterranean diet can result in somebody being happy due to being skinnier and healthier.
No, the Mediterranean diet would not make an individual happier than usual. Generally, humans dislike restrictions and enjoy indulgence, especially regarding food choices. When people feel guilty or unhappy about their choices, it is more often the product of lifelong socialization that favors external control and assumes that all individuals desire to be more "healthy," which is not an innate or naturally arising state.
I don't think the Mediterranean diet, or any diet, can contribute to a person's happiness. I think that while the diet may certainly be beneficial to a person's health, that shouldn't be confused with a person's emotional well being. Diet does not equal happiness! What you eat doesn't "make" you happy.