Many of our patients at the hospital are on low-fat, "cardiac" diets. We feed them all sorts of "healthier foods" - margarine instead of butter, decaf coffee instead of the real stuff, egg substitute instead of real eggs, and heaven forbid they have any real cheese (powdered cheese substitute is OK though). I will admit to having slipped my suffering patients a pat of real butter instead of margarine (one chemical step away from plastic, they say) from time to time - not so much out of sympathy, but out of a firm belief that putting chemicals into our bodies is detrimental, particularly when we are trying to prevent disease or heal a body from an existing pathology.
Nutrition is a messy topic - various foods, drinks, and micronutrients are constantly being volleyed from the bad list to the good list and then back. The most frustrating part of trying to eat healthily is the relative difficulty of obtaining and preparing healthy foods. Unhealthy foods tend to be cheaper, more readily available, and components in more recipes. Perhaps I'm not looking in the right place, but when was the last time one found a casserole recipe with instructions on how to use brown rice in place of white rice? I think I am fairly motivated in trying to cook and eat healthily, so I imagine the general population whose idea of cooking is a five-ingredient (and three of those are cream of something soup) one-pot sludge has the same difficulty.
I am encouraged by what I've been reading the past couple weeks in my complementary therapies class about nutrition (thankfully we've moved beyond energy fields to something actually useful). Don't give margarine to patients on a low-fat diet - teach them how to use real butter, in moderation. Don't eat low-fat foods full of chemicals - eat healthy fats like olive oil, again, in moderation. The thing that I can't get beyond is there is no support for teaching patients how to procure and cook with these ingredients. We are so used to telling patients to go do something without providing them the tools to actually go do it. My GP prides himself on his wellness focus, but the extent of dietary teaching I've received has been "eat a balanced diet and be sure to drink plenty of milk for your bones". Sure, I'll do that, and make sure margarine is on the shopping list.