Beware of all dairy products. Humans, they say, are not intended to ingest milk and milk produts after a certain age. Cow's milk is designed to (and does) get a calf up to a weight of 200 lbs. (90kg) within 2 years.
Lotsa green vegetables (not peas which is a starsh). Try a dressing of 1 tablespoon vinegar, 1 tablespoon lemon juice and two tablespoons decent salad oil. Works on salads too. Try balsamic vinegar as well. For a truly refreshing dressing use equal parts lemon juice to salad oil. For more veggie ideas try the name of the veggie on the web follwed by "a la greque." which is lemon, vinegar, oil dressing and served at room temperature.
The Fit For Life diet advocates eating everything, but not at the same meal. Have a meat, a salad and a green vegetable at one meal. At another one have starch, a salad and a green vegetable. Makes for better digestion and fewer posions/toxins in one's system. Butter is a fat, and can be used sparingly woth either "meal plan"
Beware of artificial ("diet") sweetneners. These all break down to VERY HIGHLY TOXIC substances.
Beware of fake butters. Hydrogenated oils are very unhealty. Use oil instead, preferable olive oil which is low or devoid of trans-fats. If it's liquid at room temperature (70*F to 80*F, being 20*C to 25*C) it will surely be a liquid at body temp (98.6*F or 37*F). Other (solid) fats are basially evil and murder on one's areteries. Children do need them for brain development, however.
Overall you may want to find a Mediterranean-diet cookbook. This is said to be one of the healthiest ways of eating, overall. It's low fat, high fiber and stays away from rdiuclous American diet trendiness.
And as suggested get some physical excercise, but not wrist to mouth.

They say its that one extra pound (1/2 kilo) we gain a year that robs us of our slenerness.
Now to go take my own advice.............
I guess I need to put a note in my wallet that if I ever need to be opened up for emergency surgery, wouldja please do a tummy tuck while you are at it? *LOL*