Even if we did, there will be genetic differences between you and your brother so who’s to say those genetic variations aren’t important?.
Sure they are important. But until we get to the day when we have the resources and knowledge to test everyone and make sense of the role genetics play here (looking at the map I am inclined to believe Spaniards are different enough from the English to take genetics into consideration—although that could be the racist in me speaking again), we should at least try to stay away from making sweeping assumptions like the one based on the Mediterranean diet study. We no longer tell all the kids they should drink milk, do we?
I don’t agree with that. Spain is not a walled city. There is tremendous genetic flow from between countries such that there are more similarities between individuals of Spain and other countries than there are differences, and more differences between individuals within a country than there is between populations of different countries.. If you are waiting for the day when someone can tell you that this or that particular recommendation is applicable to you but not your neighbor you will be waiting an awfully long time. I am well aware of all the efforts to make medicine more individualized but we are no where near having that kind of resolution in our data that would allow us to come up with recommendations such as the ones you are looking for.
In the mean time we can certainly make reasonable conclusions based on what we do know such that the population as a whole will live longer and better. In this particular case, any suggestion that this might be an effect limited to only to a Mediterranean population is naive. If you look at the particular diet in question it includes many features that have been extensively studied on their own. There is significant evidence that diets high in refined carbohydrates and sugar lead to increased rates of diabetes and heart disease. Similarly there is good evidence that diets high in red meat lead to increased rates of heart disease and certain cancers. Polyunsaturated fats are well known to have positive effects on lipid profiles when they are used instead of saturated fats or trans fats. Diets that include a higher intake of fish have also been linked to better cardiovascular outcomes. These studies have been done in different groups of people all around the world. The Mediterranean diet is simply a diet that incorporates many of the things we already know to be part of a healthy diet. I don’t think its unreasonable for the medical community to advise people that this is what the evidence currently implies.
We can wait longer until we have a more data but at what point is it then permissible to make recommendations? If you’re waiting for the perfect answer tailored specifically to your genetics you can sit back eat twinkies and believe that our knowledge is so imperfect that your chances of a good outcome are as good as anyone who follows current guidelines for a healthy diet but you are going to have a long wait. Lets put it another way. If we were to create two groups of Americans assigned entirely at random to eat a Mediterranean diet or a diet akin to what the average American currently eats and then follow them for 20 years which group would you bet on having the better outcome if we put some real money on it? If you have even the slightest inclination to go with the Mediterranean diet group than I would suggest that its irresponsible for the medical community to not be recommending such a diet at this point. No one is putting a gun to anyone’s head and making them eat this way. They have simply published a study that gives further evidence to something we already had significant evidence for. Anyone who doesn’t want to listen is free to eat their twinkies.