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What are the dangers of weight loss drugs?
Last reviewed: 01.07.2025
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Most women secretly dream of "super pills" that can help them shed extra pounds without any effort. But, alas, such drugs do not exist today. Most weight loss pills "work" only in combination with diet and exercise.
Meal replacements
Their main task is to replace one or more meals, reducing the overall caloric content of the diet. These weight loss products are usually released in the form of cocktails. They contain some swelling fiber and substances that reduce appetite. But the main thing in them is a suspension of amino acids, proteins and vitamins that imitate full-fledged food.
Cocktails are low-calorie. They are most often consumed instead of breakfast or lunch, and in the evening they eat a full dinner that does not exceed the calorie norm. Cocktails should not be taken longer than the manufacturer recommends. There are practically no contraindications for them. However, some women are allergic to meal replacements.
Pros: Cocktails rarely harm health, because they contain a minimum of chemical compounds. They are well suited for fasting days as a full-fledged alternative to apple, kefir and other mono-diets. When used correctly, they are quite effective.
Cons: It is difficult to stick to such a diet. If you start taking the cocktail together with regular food, you can gain weight. Meal replacements quickly become boring, and not everyone can feel the expected effect of satiety. A half-starved state reduces performance. Some women may experience difficulties with bowel movements, which disappear after returning to normal nutrition.
Appetite suppressants
The main purpose of these prescription-only drugs is to dull the feeling of hunger and help to endure a low-calorie diet. They usually act on the nervous system and can cause emotional arousal. After a short surge of energy, there is a decline, possibly physical and nervous exhaustion. They are prescribed in exceptional cases, most often in cases of severe obesity.
Pros: No feeling of hunger.
Cons: It is impossible to get rid of accumulated fat without physical exercise and reducing caloric intake. A large number of side effects. Some drugs in this group have a negative effect on the cardiovascular system. It is possible to develop psychological dependence, nervous excitability, insomnia, euphoria, sweating, dizziness.
Creating the illusion of satiety
These biologically active food supplements are taken before meals. The ballast substances included in their composition swell in the stomach and create the illusion of satiety. As a result, a person eats less than usual food. However, ballast substances do not directly affect the process of losing weight.
Many dietary supplements for weight loss from this group are made on the basis of seaweeds - such as kelp, fucus. They contain special dietary fibers that have the ability to remove excess fat from the body.
Pros: Virtually harmless. Normalizes bowel movements for those who suffer from constipation. Cleanses the intestines, removes toxins. Affordable price.
Cons: Low efficiency. The state of hunger and satiety is determined not only by subjective sensations in the stomach area. To a greater extent, the feeling of hunger is caused by the content of glucose in the blood and glycogen in the liver. Accordingly, the stomach may seem full, but the feeling of hunger still does not go away. May cause loose stools. Fiber reduces the absorption of vitamins and microelements. To prevent vitamin deficiency, regular intake of multivitamins is required.
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Diuretics
Most often, they are not used independently, but are included in complex dietary supplements for weight loss, for example, in teas. Their action is based on the fact that salty, sweet and fatty foods activate fluid retention mechanisms in the body. With the help of diuretics, this fluid is removed and creates the illusion of weight loss.
Pros: Fast weight loss. Low price.
Cons: Weight gain in this case occurs as quickly as weight loss. The amount of fat in the body remains the same. Constant use of diuretics increases the risk of health problems. Loss of potassium and water leads to muscle weakness, flabbiness of the skin, and heart rhythm disturbances.
Laxatives
Often, "weight loss" teas and capsules include laxative components. These drugs are often disguised as "biologically active supplements that activate peristalsis and normalize digestion." However, a laxative can only be used as a temporary measure that helps cleanse the intestines.
Pros: Relatively fast weight loss. Cleanses the intestines, removes toxins. Low price.
Cons: Many side effects. Laxatives are addictive: to achieve the effect, you need to constantly increase the dosage. Regular artificial bowel movement leads to the breakdown of natural mechanisms. It can be difficult to restore lost functions: after stopping taking such dietary supplements, constipation often occurs. Potassium and other useful salts may be lost. Vitamins are not absorbed sufficiently.
Fat absorption blockers
The drugs in this group interfere with the absorption of fats that enter the body with food. This can be achieved in two ways. In the first case, the action of the enzyme that breaks down fat is blocked. As a result, fats are excreted from the intestines unchanged. The popular drug Xenical, which is available from pharmacies on prescription, works on this principle.
The second method is to use dietary supplements containing chitosan to eliminate excess fat. This substance is extracted from crustacean shells. Chitosan absorbs fat molecules and removes them in an undigested form.
Pros: This type of product is quite harmless. It allows you to eat fatty foods and lose weight gradually. It can be used for a relatively long time. It also reduces cholesterol levels. Chitosan products regulate bowel function.
Cons: If a person does not eat fatty foods, the result of taking fat absorption blockers is close to zero. The effectiveness of the drugs will also decrease if you eat a lot of sweets. They can cause intestinal irritation, increased gas formation, diarrhea and "fatty" stools.
Fat Burners
One of the most common dietary supplements for weight loss today. According to the manufacturers, these drugs fight fat deposits in the body. Most often, such dietary supplements are produced on the basis of bromelain - an enzyme extracted from pineapple. This group also includes supplements based on South American guarana and garcinia cambogia.
Meanwhile, bromelain only helps digestion. Unfortunately, this enzyme is unable to reach subcutaneous fat. The effect of bromelain is very insignificant. Most scientists believe that people lose weight not so much from bromelain, but from self-hypnosis.
The modern market also offers "fat burners" based on extracts of the fruits of Garcinia cambogia. It is believed that the fruits of Garcinia slightly suppress appetite and stimulate the consumption of fat reserves.
Another popular plant is South American guarana. Guarana is a source of caffeine, which stimulates the nervous system and helps the process of fat breakdown. This component is contraindicated for hypertensive patients, patients with arrhythmia, and angina.
Most nutritionists are confident that the effect of "fat burners" is noticeable only with strict adherence to a diet and regular exercise.
Pros: Bromelain improves digestion. Garcinia slightly reduces appetite and stimulates metabolism. Guarana stimulates energy expenditure and fat breakdown.
Cons: Relatively low efficiency. Guarana can cause side effects: increased heart rate, headaches, nervousness. Long-term excessive use of caffeine-containing supplements can cause insomnia and addiction.
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Beware of fakes!
Of the weight loss products, Xenical, Dietrin and Meridia are medicinal products. They must be dispensed only with a doctor's prescription. An over-the-counter product is "Nova Figura Dr. Theiss", registered as a laxative.
The remaining products are biologically active food supplements. It should be especially emphasized that some manufacturers do not indicate the full composition of the drug on the labels. This is dangerous, since there have been cases when potent substances were found in them during examination - for example, ephedrine.
To avoid buying a counterfeit or dangerous drug, follow these rules:
- buy dietary supplements only in pharmacies;
- don't hesitate to ask for hygiene certificates confirming safety;
- Be sure to study the composition of dietary supplements;
- check the expiration date and production date;
- Read the manufacturer's recommendations for dosage and schedule of use carefully.
All medications and active supplements for weight loss should be taken only after consultation with a doctor.