Taamar wrote:
Not true. It's totally possible to get every nutrient you need from a plant source, it just requires a bit more effort.
This. Unfortunately, many vegetarians and vegans exercise a poor diet, but it doesn't have to be this way. It doesn't even require that much effort -- just a little education. I don't really advocate vegetarianism myself, but there are a lot of combinations of vegetables that will result in complete nutrition that is in every way as adequate as a diet containing meat. A classic example of this is:
Corn + beans = complete protein (all amino acids are present)
The mezo-americans had a pretty solid diet going. And now you know why Mexican food is what it is.
Really, though, the "secret" to a mostly-vegetarian diet is the same as any other healthy diet -- plenty of variety. You want some grains, nuts, seeds, legumes (beans), leafy vegetables, fruit, and starchy vegetables (ex. potatoes). That is, don't dwell on a just a single category and you'll be fine. I always cringe when I see someone go on a "vegetarian" diet that consists almost entirely of pasta and potatoes because they don't really like green vegetables. Not only is that sort of high-starch diet nutritionally inadequate, it's also obesity waiting to happen.
For this sort of diet, a good rule of thumb is that a serving of meat is about the size of a deck of cards (2-3oz), and you should aim for about 2 servings a day.
Learn to like whole grains if don't already. They're much better for you. And when you're buying bread, make sure you're buying 100% whole wheat bread. Bread that merely says "whole wheat" (without the "100%") is hardly better than white bread. Similarly, most breakfast cereals are not particularly that great since they don't use whole grains. They're not bad for you, but nutritionally speaking, you'd be better off just eating some cheese toast or oatmeal.
The orange juice you buy in the grocery store is incredibly high in sugar and calories compared to just eating an orange (or two).
This is kind of more of a general cooking tip but get a good collection of spices and don't be afraid to season things. Yes, you can over-season, but in my experience most people err the other way. Seasoning adds a lot of flavor with essentially 0 impact on nutrition. People are often used to being lazy with their seasoning because they eat a diet that is high in fat and sugar. As Taamar contends, fat and sugar are a "lazy" (but effective) way to make things taste better. This leads a lot of people to try a healthier and diet and then give up because it "tastes bland" or just doesn't taste good. The reality, though, is simply that most people don't know how to cook anymore. Fortunately, at a non-professional level, it's mostly the case that -- as my mother likes to say -- "if you can read, you can cook". I don't know if it's possible to get your hands on some of the Weight Watchers cookbooks without being a member, but I can vouch that they have a lot of really good recipes that are low-calorie and that conform to the sort of vegetable/meat ratio you're looking at.
A teaspoon of honey will sweeten a remarkably large bowl of strawberries (or other fruit) for far less calories than it would take to sweeten them with sugar.