Analysis of the fundamental role of diet therapy and the function of nutrients in weight loss
Regarding the treatment of obesity, medical experts have discovered through long-term medical practice and by summarizing past treatment experiences and lessons learned that the fundamental treatment measure is to manage diet effectively and long-term and to develop good lifestyle habits.
Since obesity is a long-term process, self-treatment and self-monitoring are essential for obese individuals.
Choosing the right type and method of dietary therapy is crucial in treatment.
Currently, there are many methods of treatment using diet and foods for weight loss, some of which have been commercialized, bringing great convenience to patients undergoing home treatment.
It is worth noting that some products are produced to cater to the urgent desire of people who want to lose weight, and often lack clinical practice and scientific basis, but become popular for a time with the help of advertising.
For example, a grape-colored liquid from the United States is touted as having "magical powers" and can "burn fat," but many people experience diarrhea and discomfort after consuming it, finding it unbearable.
Some obese people are not clear about the principles of weight loss and are eager to achieve quick results, blindly pursuing "eating less" or not eating at all. Not only do they fail to achieve their goal of weight loss, but they also affect their health.
Treatment of obesity should be practical and individualized, taking into account factors such as family history, birth condition, environmental factors, dietary habits, living habits, appetite, nature of work, and activity intensity. The focus should be on changing the excess energy intake of obese individuals and reducing the intake of food calories.
It must be pointed out that controlling dietary calorie intake can effectively reduce the weight of obese people, and the short-term effects are obvious, but long-term adherence is necessary to maintain and consolidate the effects.
If obesity occurred during infancy or early childhood, or if it is constitutional or mixed obesity, the fat cells have already proliferated significantly, making it even more difficult to continuously reduce weight or reach a standard weight.
Based on the traditional customs of the Chinese people, this type of patient is not very common, and appropriate dietary therapy can achieve good results for most obese people.
I. The Role of Nutrients in Dietary Therapy for Obesity
(a) Sugar, i.e. carbohydrates.
The carbohydrates needed by humans mainly come from plant-based foods, such as wheat, grains, potatoes, and fruits.
Each gram of carbohydrate actually generates 16.736 kilojoules of heat energy in the body (4 kilocalories, 1 kilocalorie = 4.184 kilojoules).
Excessive carbohydrate intake can stimulate increased insulin secretion, causing absorbed sugar to be converted into fat and promoting water retention in the body.
Carbohydrates are rapidly and completely absorbed in the intestines and utilized in the body. They have poor satiety and can easily lead to overeating. Therefore, when treating obesity through diet, the intake of carbohydrates should be appropriately reduced.
(ii) Fats, mainly from two sources: one is animal fat, such as beef tallow, mutton tallow, and pork tallow; the other is plant-based fat, such as soybean oil, peanut oil, and sesame oil.
The normal human body needs 0.8 to 1.0 grams per kilogram of body weight.
One gram of whole fat generates 37.66 kilojoules (9 kilocalories) of energy in the body.
Fat in food can inhibit gastric juice secretion, prolong the time food stays in the stomach, and make it more resistant to hunger.
(III) Protein.
Generally, adults in my country need 1 to 2 grams of protein per kilogram of body weight per day.
One gram of protein generates 16.736 kilojoules (4 kilocalories) of energy in the body.
Protein is a key component of the diet in the treatment of obesity.
Based on the important role of protein in the human body, people have designed various high-protein diets.
Lean meat, poultry, eggs, skim milk, and cheese are high-protein, low-fat foods with high nutritional value.
Fish is not only a high-protein food, but also contains a large amount of unsaturated fatty acids, which can help lower cholesterol.
Protein foods are highly satiating, and after consumption, the pancreas secretes more glucagon, which promotes the breakdown and utilization of fat.
(iv) Water.
Water is an essential element for human survival.
In addition to the water contained in the food we eat, the human body also produces water through the metabolism of proteins, fats, and carbohydrates in food or tissues.
Sodium salts have a water-retaining effect, while potassium and calcium salts have a diuretic effect. Therefore, a low-sodium diet is recommended when correcting obesity.
(v) Minerals, trace elements, and vitamins.
Minerals, also known as inorganic salts, such as calcium, phosphorus, magnesium, sodium, potassium, chlorine, and sulfur, are abundant in the body and are called macroelements; while iron, iodine, zinc, copper, chromium, fluorine, and tin are present in very small amounts and are called trace elements.
Vitamins are a class of organic compounds with different functions that participate in many basic life processes in the body.
They work synergistically and are indispensable factors in the metabolism of carbohydrates, fats, proteins, and water.
A deficiency in zinc, cobalt, chromium, etc., can lead to physical development disorders and increase the risk of obesity, diabetes, and arteriosclerosis; a deficiency in vitamin B can lead to fatty liver and hyperlipidemia.
When treating obesity, regardless of the chosen dietary therapy, it is essential to supplement with sufficient vitamins, appropriate amounts of minerals, and trace elements.
II. What are the different types of dietary therapy for obesity?
(a) Low-calorie diet
This refers to a total daily calorie intake of <4184 kJ (1000 kcal) or <83.68 kJ (20 kcal) per kilogram of body weight per day.
Based on the different proportions of carbohydrates, proteins, and fats in the diet, it can be further divided into:
1. Maintain a balanced diet.
This means reducing carbohydrates, proteins, and fats by approximately the same proportion, which means reducing the amount of these three substances by the same amount based on the original diet.
This type of diet is probably the most common choice for patients who are unfamiliar with the nature of obesity.
Because the diet contains a relatively high proportion of carbohydrates and a relatively low proportion of protein and fat, the feeling of hunger is intense and difficult for users to endure, often resulting in failure in a short period of time.
2. High-fat diet.
This refers to a low-calorie diet that is primarily composed of fat.
Fat has strong satiety-resisting properties and can inhibit the feeding center in the hypothalamus, thereby reducing the desire to eat and thus reducing calorie intake.
However, excessive fat intake can easily lead to aversion to greasiness; fat particles entering the bloodstream increase blood viscosity, which can aggravate or induce existing cardiovascular and biliary system diseases, and produce a large number of ketone bodies that affect the body's metabolic processes, so it is not suitable for long-term use.
3. High-protein diet.
The diet should consist mainly of protein-rich foods or include a certain amount of fat.
This diet provides the body with the protein it needs and also has a certain degree of hunger resistance.
It's not very oily, so it's relatively easy to accept.
Its main drawback remains the tendency for ketone bodies to be produced in excess.
4. A vegetarian and high-fiber diet.
It mainly refers to vegetarian food derived from plants.
The average Chinese person consumes 10-20 grams of plant fiber per day.
A diet containing more than 25 grams of dietary fiber per day is considered a "high-fiber diet".
The protein in a vegetarian diet mainly comes from legumes, which have a limited range of amino acids and are less nutritious than animal and fish proteins, and are also less effective at keeping one hungry.