1) Eggs
This is seriously a miracle food. I have had eggs almost everyday for breakfast. Some people say to throw out the yolk, but in my honest opinion that is one of the worst mistakes you can make while dieting. They are so dense in micro nutrients and keep you so full you're not even hungry when it's lunch time! They're so easy to make, just boil em' mash em' or stick em' in a stew. And if you think dietary fat and cholesterol contributes to heart disease...well, you're on reddit and you're informed so you won't think like that. Don't believe me? That's good, it makes you skeptical.
2) Apples (with peanut/almond butter)
Even though I was on a ketogenic diet, I had apples before a weight lifting session. They're on the low glycemic spectrum, and even lower if you add fat with it. If you want a good snack, add some peanut or almond butter (almond butter is healthier, better monounsaturated fat to polyunsaturated fat ratio) to lower your insulin and blood sugar levels and stabilize them. If they're stable, so is your appetite.
3) Walnuts
Walnuts rank above peanuts, almonds, pecans, pistachios and other nuts. A handful of walnuts contains almost twice as much antioxidants as an equivalent amount of any other commonly consumed nut. But unfortunately, people don't eat a lot of them
4) Ground beef
I make burgers (minus the bun), cook chilli (minus the beans), and a nice stir fry with onions, peppers, and carrots with a good amount of beef in there. There are studies out there showing the fat in beef may raise testosterone levels, and that's good, even if you're a woman.
5) Chicken Breast
A cheap protein source when your protein that day is low but you don't have much room for calories. I put olive oil in a pan and but it on low. Put a lid on it, come back 20 minutes later, and it's a nice, tender, juicy chicken breast steak. If you grill your chicken breast on medium, or even high heat gasp, you're asking for dry chicken.
6) Spinach and Kale
Seriously, I cook this with everything. Put it in eggs for breakfast, throw in a cup of it in a salad, do whatever! It's high in electrolytes (potassium), and this is important when dieting to prevent you from being light headed all of the time and prevent muscle cramps at night. Kale is the most micronutrient dense green vegetable out there. One cup has 10% Calcium, 170% Vitamin A, and a lot of Vitamin C which makes eating fruit obsolete.
7) Yams
Even though I'm a low-carb guy, I still have sweet potato fries or a boiled yam before a heavy workout to keep me lifting my weights. Before I dieted my bench press was 210, now it's 180. I know for a fact if I didn't eat properly my bench would've been at 135 lbs. And I would've been mad, and I should be mad. Lots of vitamins in this stuff and more filling than potatoes (potatoes = sugar).