There are two ways of doing things. One way is to get all kinds of info, work out a game plan, and then jump in. Another way is to adopt change a little bit at a time. So it depends on what kind of person you are. But in a nut shell, the idea is you eat a lot of meat, vegetables, and a moderate amount of fruit. WHole fruit is better as it fills you up with less sugar intake per bite. Now you can get into a whole 10 page essay on fruit but the gist is don't overdo it as it has a lot of sugar in it. YOu ditch or restrict grains, especially wheat, and that includes whole grains. Because grains are very new to the human diet and the body is not well adapted to processing them. Grains are in bread so paleos ditch or restrict bread consumption. Sugar is also ditched or restricted. Paleos freely eat fat and often prefer fish (especially salmon because of the omega 3s. We also prefer saturated fat because it's our natural food source which is naturally stable and not rancid before you eat it. (Vegetable oils are rancid and need to be perfumed by the manufacturers in order to hide the stench) That is the most basic concept of making your food intake more like what our ancestors ate for most of our evolutionary history.
Beyond that, details vary as we all have our opinions and also because each person's genetics and dietary needs will vary. People trying to lose weight or with unstable blood glucose levels may try to limit carb intake more steeply while those trying to build muscle might eat more carbs. Many paleos distrust diary but a fair number will still eat fermented diary like cheese, kefir, plain yogurt, etc. Many paleos distrust added salt. Many paleos shun carbs but some will eat a fair amount of tubers like potato and sweet potato. Many paleos believe in skipping meals and fasting from time to time, but others find that doesn't work for them. Most, if not all, paleos feel that animals raised naturally, eating their natural foods, are also healthier in their life and healtheir for us to eat.
Paleo is not really any one diet, but it is a basic concept of trying to figure out both what our bodies were probably designed to eat, which we feel is probably much like what our ancestors ate for thousands of years, and is probably not much like the very new foods now available, like grain oils, that we have not had time to evolve towards. Eating paleo is also about looking at the science behind the concepts and cross checking history with science as much as possible such that we can come at the problem from two angles at once. How to eat healthier? That is the main question!
There are great answers here:
We'll probably merge these three questions very soon.
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