Since we are not made of only one nutrient, some diets look pointless. For example, the so-called meat diets that allow only meat (proteins) and no carbohydrates seem logical, but it is a fact that our brains use only carbohydrates and nothing else. This explains why some people become very nervous when on a meat diet regime.
Healthy lunch advice
As for a healthy lunch, it can be very light and consisting of tuna fish salad, which stomach will digest quickly, it has all the things our body needs and it can be bought or made at home. Homemade meals ensure us that, the food used is fresh. Good source of carbohydrates are fruits or natural juices made of fruit and not with the help of chemistry. Coffee is allowed but not sweetened with sugar; what's more, even artificial sweeteners should be avoided, if possible. Lunches should be different each day and should not include large quantities of food, because it will only be a problem for a stomach to process. Healthy lunch options might include meat, with poultry and fish as the first choice, because of very low cholesterol level. All sorts of salad with small amounts of cheese and meat are also welcomed.
The most important thing in each and every diet is to set a goal, a weekly one, monthly one and the final one. It is much easier to think of a weekly goal, than to think of what might or might not happen in a couple of months. But the final goal has to be in mind when problems in a diet emerge, or when a diet cycle is broken for example. Eating more than allowed in a diet is not such a big problem, on a long run. Final achievement is a final victory over extra weight, so it is ok if a few battles are lost along the way.