HYPOCALORIC CONVENTIONAL DIET
This includes those balanced diets (maintaining a sufficient and proportional intake of the principle food groups) but with an inferior caloric intake than the necessities of the individual (hypocaloric) but more than 800 Kcal/day.
a) Energy
In studies done it has been observed that no normal adult has a basal energy use (en repose) of less than 1200 Kcal. Thus, once the total energy use (done by adjusting for physical activity) is established it is presumed that a diet of 1000-1500 Kcal/day should be sufficient to produce an acceptable reduction. As a general rule, to reach a reduction of 5-10% of weight in 3-6 months, a diet that decreases the caloric intake by 500-1000 Kcal/day of that which is needed by the individual is prescribed.
b) Carbohydrates
(energy value: 4 Kcal/day)
The contribution of carbohydrates should constitute 50-60% of total calories. Restricting simple sugars is recommended, as well as products rich in starch and fiber. What should be increased is the proportion of cereals, vegetables and legumes.
A dietary consumption of less than 80-100 g of carbohydrates stimulates the production of cetonic bodies or cetosis (through the degradation of fats and proteins of the organism), making for a significant loss of water and salt in the urine.
c) Proteins (energy value: 4 Kcal/day)
The daily recommendations for a normal adult (in the absence of circumstances like pregnancy, lactation or infancy or pathologies like renal or hepatic insufficiencies) are from 0.7-0.8 g/day of protein of high biological value; however the beginning of treatment with a hypocaloric diet can provoke a loss in proteins, thus it is recommended that an increase contribution of up to 1g/day of protein, around 15-20% of the total caloric value of the diet.
The recommendations for what type of proteins they should be, are primarily those with high biological value (where there is adequate access to the different essential amino acids) and low in fat content: white fish, white meat, non-fat lactose, egg whites and legumes.
Hypocaloric hyperprotein diets are tolerated very well and can have certain advantages, more so at the beginning of treatment, in that protein increases the sensation of fullness and decreases energetic yield (it is the nutrient that requires the greatest caloric expenditure for its metabolism and use). However, a diet high in protein and low in carbohydrates produces a state of cetosis.
d) Fats (energy value: 9 Kcal/g)
Fat in the diet stimulates ingestion and promotes weight gain through its satisfying capacity and large caloric density. To carry out a diet low in fats you have to decrease the ingestion of fats and pure oils like cream, butter and margarine, sausages and cold meats, fatty meats and blue fish and vegetable oils, favoring the consumption of raw or steamed, baked, grilled or roasted foods, while avoiding sauces, fried and fatty stews.
The daily necessity of essential fatty acids (linoleic and linolenic acids) are 5-10 g/day, that can be covered through the ingestion of 15-25 g of fats in a diet. This presumes that a contribution of total fat does not exceed 30% of the total calories of a conventional diet, with which the saturated fatty acids (associated with an increase in the risk of cardiac disease) should not represent more than 10-15% of the total calories of the diet.
Any hypocaloric diet should not be done with an indiscriminant decrease in fats, in that they are a resource if essential fatty acids and liposoluble vitamins.
e) Dietary fiber
Fiber contributes to a reduction in levels of cholesterol, prevents cardiac disease, reduces constipation and is useful in cases of obesity as it has a filling effect. Recently, recommendations suggest a daily intake of 20-30 g/day or 10-30 g for every 1000 Kcal ingested/day, maintaining a proportion of insoluble fiber/soluble fiber of 3:1.
f) Vitamins and minerals
Vitamins, minerals and oligoelements are essential contributers to a healthy diet and should be administered during dietary treatment of obesity. When a diet has less than 1200-1300 Kcal/day the amount of vitamins (vitamin B groups and liposolubles) and minerals (fundamentally iron, zinc, magnesium) can be seen as insufficient according to the current recommendations, and it is advisable to add a complete multi-vitamin and commercial mineral.
g) Water
To replace losses, 2000-2500 ml of water per day should be part of the diet. The amount of water in a calorically normal diet is from 800-1000 ml, where as the remaining needs are met by other liquids. In a hypocaloric conventional diet, as a less foods are consumed, the water produced by these foods is reduced and therefore it is recommended that an adequate intake of water should be met (1500-2000ml)
h) Alcohol (valor energético: 7 Kcal/g)
Although the moderate consumption of wine and beer has been shown to have beneficial cardiovascular effects, alcohol is an important resource of empty calories and should be excluded in a hypocaloric diet.
Following these general guidelines, this diet is made up to include the different elements in function of their composition in the principle qualities that they contain while keeping in mind the different food balances that all diets should respect. It is convenient to divide intake into various meals throughout day to avoid the sensation of hunger. Eating 5 meals a day to avoid snacking between hours is recommended. These meals should be 3 large (breakfast, lunch and dinner) and 2 smaller complementary meals or snacks (mid-morning, mid-afternoon).
A dietary treatment can begin by giving a specific menu or by giving options of interchange at the beginning. When administering a specific menu, rigidity should be avoided and done according to the tastes of the patient; after a few weeks the patient should start, on their own and dutifully instructed, to begin an interchange of foods. In this way the patient will be capable of carrying out and learning to consume an appropriate and varied diet while avoiding transgressions in the diet or nutritional deficiencies.