Here is an article that I found pretty much agreeable to my philosophy of a healthy diet and continued healthy lifestyle. I agree that extreme diets may not be easily sustainable and people lose their enthusiasm for them over time.
The 7 Habits of Highly Successful Eaters « Real Life Nutrition
I try to always prepare and serve our plates with the most part COLORFUL fruit and vegetables with small portions of meat or fish. (about four ounces before cooking for dinner, about two ounces or less for lunch.) I try to limit the fat in sauces. I try to avoid preserved lunch meats of any kind. I feel that we need some idodized salt to keep our thyroid functioning properly. High fat salty snacks aren't great for you either, we know that we can't just eat ONE potato chip.
I try to limit sweets to special times and not every day. I encourage a lot of water drinking. We drink milk and put it in our coffee...which I believe is good for you...Coffee and especially skim milk. There are very few fruits and vegetable that don't appear on our table on a regular basis and we know the difference between high starch vegetables and high fiber ones.
I am not concerned as much as some about food processing. The benefits of preservation in lack of spoilage are real. I try to prepare food "from scratch" as much as possible and am always a little sceptical about claims of produce being raised without insecticides etc. How can we really know? So I try not to worry about it. I favor fish and chicken over pork and beef as far as what I serve most. But I do prepare the red meats a couple of times a week. I don't worry about white flour but try to get whole grain bread most of the time. I also don't think that honey or maple syrup affect us any differently than brown or white sugar. Sugar is sugar. I think we don't need much in the way of carbohydrates in our diets.
I try to keep moving. I used to jog and now I walk. I used to play tennis and now I hope that the frequent golf kind of makes up for it a little. I clean my own house and pull weeds out of our beds and when it gets cooler I will mow the lawn again. I like to dance and I really need to start biking. But...I don't want to fall.
My Sweetie is always on the go and fixing things all around the house, planting stuff, dragging stuff around for me and he plays a lot of golf and walks with me. Our daughter walks in the house 30 minutes each morning. We are no longer in our fifties or sixties when we really moved a lot more.
We all blessedly at this point feel good and have good test results from our twice a year check ups.
I don't expect, or encourage or suggest anyone do anything like I do. This works for me and for us.
Most of us know what we are doing right or wrong.