waistline is unstoppable. They grab any miracle treatment that will dissolve the fat as if by magic and come lend to establishments where the neon lights, star products advertised for weight loss. In irresistible form of biscuits, milk shakes, bars, chocolate pudding and even dietary presents the solution of all problems. But do you know if they really effective? And most importantly, are harmless to your health? You know what they contain or how they work? Meal replacement, what are they? The law defines the meal substitutes, normally used in a diet low in energy, as "those which, when used according to the manufacturer's instructions, replace all or part of the daily diet." It is marketed as smoothies, soups, bars, cookies, custards, creams and even chocolates are a substitute for meals or help whet the appetite when hunger pinches. Its effectiveness lies in providing a low caloric intake and energy between 200 and 400 kcal less than a normal meal. This forces the body to use fat reserves to keep going, which means a weight reduction. But to offset this low in energy, containing a balanced dose of vitamins (A, B, D, E, C, thiamin, riboflavin ...), minerals (zinc, copper, iodine, selenium, potassium ...), fiber (between 1 5 and 3 grams each), protein (containing essential amino acids), carbohydrates and essential fatty acids. Where is their power to satisfy? Being so small, the greatest fear is that they satisfy hunger. But this is not true. The meal replacement products are extremely sated power. With one rod you'll feel you've eaten a full meal. Why? The secret lies in leptin; a protein produced by the liver in food intake in the body and that is what helps create the feeling of satiety. Hot and liquid preparations are best stimulate this production, while solid products need to be complemented or cold liquid. Therefore, you should chew slowly and drink two or more glasses of water with each stick, biscuit, chocolate or custard, to maximize the feeling of being "full." All these products can be divided into two groups: those that completely replace a meal, such as bars, puddings, smoothies and even soups or snacks to avoid snacking between meals, like cookies or chocolates. Expert opinion Nutritionists agree that dietary products substitutes for meals are not a good option for weight loss. Thus, Loles Vives, BA in Biology and Masters in Dietetics and Nutrition, believes that "as you can lose weight without resorting to such preparations to the diet become monotonous, boring and uncool, as well as unbalanced. €? That said, made a clarification "provided that it is exceptionally may be a good resource for a day when time is not available or where circumstances prevent food as God intended. Now in summer, for example, can be useful on the beach, in the countryside, swimming pool ... but if they are a resource and not become a habit. €? If consumed these products should always be the manufacturer's conditions. Moreover, "during the days you take a stick or similar, it is advisable to make fresh produce in the other main meal of the day. Now in summer, we can not manage the array of vitamins, minerals and other substances (antioxidants) that will offer seasonal products: vegetables, fruits, etc.. And it is a sin without the wonderful fresh fish we have in this time of year €?, Says the expert nutritionist. Moreover, according Loles, "a good weight loss program should serve not only lose the weight but also to learn to take good eating habits. And the bars and milkshakes do not allow it. €? Hazards of prolonged use Although the diets that rely on products (or calorie VLCD, original English meaning of "very low calorific value ') is a dramatic visible results in the short to medium term, prolonged use of them (more than four weeks) can have unwelcome consequences for the organism. And although more and more nutritionally complete, staying only on the basis of sticks or shakes can: Trigger nutritional deficiencies. Cause constipation and hemorrhoids because of the lack of fiber. They are ineffective in treating obesity is important, as well as lead to serious side effects. The kilos are retrieved as easily re-establish the usual eating habits because they do not adequately help change dietary habits. Are monotonous. And it can be very expensive to your wallet. Given this, it really worth it? The best solution is to adopt a healthy, balanced diet based on Mediterranean cuisine, and seasoned with a little exercise. It will be more palatable and your health.