Weight loss generally occurs due to an inadequate calorie supply for the body’s energy needs or food assimilation disorders, such as improper nutrient absorption. It is important to note that an increased metabolic demand leads to a higher caloric requirement. Failure to meet this increased demand with adequate calorie supply results in a negative energy balance, leading to the burning of stored fat tissue and subsequent weight loss.
Causes
In healthy people, weight loss is most often caused by a lack of energy and nutrients in the diet. They contribute to, e.g., skipping meals, eliminating selected foods, or intense physical exercise.
Decreased Appetite
Reduced appetite, stemming from a demanding lifestyle, depression, or prolonged fatigue, can lead to inadequate nutrient intake and calorie deficiency. In unwell individuals, diminished appetite is frequently attributed to the progression of the underlying illness, medication-induced nausea, physical weakness, and difficulties with self-feeding. Moreover, patients often experience insufficient food intake due to aversion caused by pain or gastrointestinal issues such as diarrhea, vomiting, and nausea.
Diseases
However, sometimes weight loss (exceptionally rapid) is a sign of illness.
Gastrointestinal Disorders
Gastrointestinal disorders significantly impact body weight. It is imperative to observe any abdominal discomfort, changes in stool nature, consistency, frequency, and the presence of blood or mucus. In such cases, stool examination and diagnostic assessment may be necessary for conditions including:
- Inflammation of the gastric mucosa and duodenum, gastric and duodenal ulcers, and gastroesophageal reflux disease
- Chronic inflammatory bowel diseases such as Crohn’s disease and ulcerative colitis
- Celiac disease and other malabsorption syndromes
- Parasitic diseases
- Gastrointestinal cancers
Diabetes
Additionally, if weight loss is accompanied by excessive thirst and frequent urination, diabetes may be indicated. Blood glucose concentration measurement is essential in such instances.
Thyroid Gland Conditions
In the context of weight loss, the activity of the thyroid gland is a significant factor to consider. Hyperthyroidism, characterized by an excess of thyroid hormones that elevate and hasten metabolism, commonly leads to weight loss. This condition is often accompanied by symptoms such as rapid heartbeat, profuse sweating, diarrhea, protruding eyes (a hallmark of Graves’ disease, an autoimmune disorder), trembling hands, as well as feelings of anxiety and irritability.
Another endocrine disorder, pheochromocytoma, involves the overproduction of catecholamines such as adrenaline and norepinephrine. Its symptoms can resemble those of hyperthyroidism, including elevated heart rate, high blood pressure, headaches, anxiety, abdominal discomfort, and nausea. Due to an accelerated metabolism, individuals with pheochromocytoma also experience weight loss.
Hematological Condition
Furthermore, suppose general weakness, pallor, swollen lymph nodes, limb pain, and easy bruising accompany weight loss. In that case, it may indicate a hematological condition (blood disorders) or hemato-oncological issue (cancer development in various sites often correlates with significant weight loss). In such cases, prompt consultation with a healthcare professional is imperative.
Other
Rapid weight loss is often observed in various chronic diseases such as chronic kidney disease, heart failure, liver failure, and neurological disorders. This weight loss is a consequence of the body’s deterioration due to the underlying disease, which is further exacerbated by appetite disturbances, either as a direct result of the disease process or as a side effect of medications.
Eating Disorders
It is not uncommon, particularly among adolescents and young women, for intentional weight loss efforts to be concealed from loved ones. This behavior is often driven by a perception of being overweight and unattractive, a lack of self-acceptance, and a desire for perfection.
It doesn’t always take the extreme form of anorexia, but you have to be very careful. You should be concerned if someone skips shared meals and prepares them themselves, wanting control over every ingredient. Patients suffering from eating disorders often tell their loved ones that they have already eaten out when in fact they are starving themselves. Additionally, in addition to diet, patients begin to exercise intensively.
Families should vigilantly monitor individuals exhibiting such behaviors, as early detection of anorexia can prevent severe physical deterioration and facilitate timely psychiatric and psychotherapeutic interventions, thereby increasing the likelihood of recovery, which, regrettably, is not always straightforward.
Problems Losing Weight
You’ve tried everything, but still wondering can’t lose weight. There may be many reasons, from the most obvious, such as poor eating habits, to severe diseases that are difficult to diagnose. If you want to learn how to lose weight, you need to know the most common reasons why weight loss doesn’t work. It may turn out that it will be necessary to consult a specialist in the weight loss process.
Bad Eating Habits
An inappropriate diet is the most common cause of overweight problems. Unfortunately, we often cannot lose weight even despite dieting. It turns out that many people misinterpret dietary recommendations.
Particularly harmful are “light” products, which, when consumed in too large quantities, also lead to excess weight. On the other hand, many people approach their diet so strictly that after a few days of fasting, they start eating with a doubled appetite.
That is why a dietitian is particularly helpful in establishing an appropriate menu, as they will individually balance the meals so that you do not feel like snacking between them.
No Movement
In addition to a proper diet, exercise is essential. Its lack causes our metabolism to slow, and the body enters the “storage of reserves” mode. If you can’t lose weight, it’s time to move.
To avoid getting discouraged, start with regular walks. Swimming or aerobics will also work well. Only after improving your fitness can you think about more strenuous activities.
Dehydration
Lack of proper hydration of the body leads to slower metabolism. Moreover, some research shows that many people misread their thirst and instead of reaching for a glass of water, they choose a snack.
Therefore, you should develop the habit of drinking water regularly. Limiting alcohol is also extremely important in the weight loss process because it is very high in calories and leads to additional dehydration.
Hypothyroidism
The question “Why can’t I lose weight?” is often asked by people suffering from hypothyroidism. Hypothyroidism usually affects women, and the incidence of the disease increases with age.
It is difficult to lose weight with hypothyroidism because the reduced amount of thyroid hormones results in a slower metabolism. This also involves:
- Feeling weak
- Excessive sleepiness
- Problems with concentration
- Easy freezing
- Swelling of the eyelids and hands
The diagnosis is made by checking the level of the TSH hormone, which regulates the functioning of the thyroid gland.
Stress
In stressful situations, the body releases large amounts of glucocorticosteroids, including cortisol. High concentrations of this hormone persisting for a long time hurt the entire body. One of its effects is the appearance of abdominal obesity while maintaining slim limbs. It doesn’t help that many people cope with stressful situations by snacking.
Sleep Deficiency
Sleep deficiency has a similar effect on the body, as it also increases cortisol levels in the body. Two other hormones also come into play here: leptin and ghrelin. An increase in leptin levels signals the body that it is “full,” while when there is a lack of sleep, the leptin level decreases, so we constantly feel hungry. At the same time, the stomach produces more ghrelin, which increases appetite.
Medications Taken
The side effects of taking some medications make losing weight impossible. Therefore if you cannot lose weight and are regularly taking prescribed pharmaceuticals, ask your doctor if they may be causing your weight problems.
Particular attention should be paid to:
- Corticosteroids
- Antidepressants
- Beta-blockers
- Hormonal contraception
What To Pay Attention To?
When looking for the cause of weight loss, first of all, you should pay attention to the diet and determine whether it is appropriate both in terms of quantity, i.e., whether the caloric content of the food consumed is suitable for the energy demand of a given person, and in terms of quality, i.e., whether there are deficiencies of specific nutrients. To do this, you must conduct a thorough diet interview.
At the same time, it is necessary to pay attention to the symptoms accompanying weight loss, mainly from the gastrointestinal tract, which could suggest the occurrence of absorption disorders (including vomiting, diarrhea, abdominal pain) and general symptoms (e.g., fever), and ask about past diseases (especially chronic, infectious or mental), medications used or lifestyle changes (increased physical activity).
Diagnosis
Physical examination, in addition to sagging, inelastic skin, lack of subcutaneous fat tissue, and muscle atrophy, may also reveal symptoms and signs of hypo- or avitaminosis, such as keratitis, lesions in the corners of the mouth or paresthesia.
Basic laboratory tests are essential in diagnosing weight loss and weight deficiency. Urine testing allows for the detection of protein, glucose, or amino acids leaking into the urine, as well as for diagnosing galactosemia or pentosuria. Still, it should be remembered that the latter two diseases are sporadic in adults. Examination of stools can reveal the presence of starch grains, undigested meat fibers, or excessive amounts of fat, which may indicate the occurrence of food digestion and absorption disorders.
The examination also enables the identification of blood in the stool or the existence of gastrointestinal parasites. To rule out liver disorders, it is essential to evaluate the levels of aminotransferases (AST, ALT) and gamma-glutamyl transpeptidase (GGTP) in the serum, as well as to conduct protein electrophoresis and measure the prothrombin index, which serves as a non-specific indicator of the liver’s capacity to produce proteins, including coagulation factors. Additionally, contrast and endoscopic assessments of the gastrointestinal tract or imaging of the abdominal cavity (ultrasound, computed tomography (CT)) are crucial components of the differential diagnosis.
When conducting a differential diagnosis for weight loss, it is important to consider conditions such as severe congestive heart failure, primary lung tumor, metastases, and chronic obstructive pulmonary disease. In these cases, increased respiratory effort may lead to higher energy demand, and weakness and shortness of breath may cause anorexia. Therefore, a chest X-ray examination should not be overlooked.
The presence of an accelerated erythrocyte sedimentation rate (ESR) may indicate the presence of chronic infections or systemic diseases. When conducting a differential diagnosis, it is important to consider testing for antibodies against HIV, as weight loss can be substantial in the context of AIDS, often with a polyetiological background involving infections in the gastrointestinal tract caused by Candida, Cryptosporidium, Herpes Simplex, Kaposi’s Sarcoma, or Lymphoma. Additionally, decreased appetite due to depression or encephalopathy may also contribute to weight loss in the gastrointestinal tract.
When exploring endocrine causes of weight loss, hyperthyroidism, and metabolically uncontrolled diabetes should be prioritized due to their high frequency. The weight loss in this scenario is attributed to the heightened metabolic rate. Physical examination typically reveals tachycardia or rapid atrial fibrillation, fine-wave muscle tremors in the fingers, restlessness, warm and moist (“velvety”) skin, and goiter.
When hyperthyroidism is suspected, hormonal tests are necessary to evaluate TSH, FT4, and FT3 levels. For an accurate diagnosis, hormonal diagnostics may need to be supplemented with a thyroid gland ultrasound examination, determination of antithyroid antibody titers, and potential fine-needle aspiration biopsy of the thyroid gland (FNAB). In cases where hyperthyroidism is suspected, rare causes such as pituitary thyroid stimulating adenoma or ovarian goiter should also be taken into consideration.
Uncontrolled diabetes, particularly type 1, is often associated with weight loss. Typical symptoms of this condition include increased urination (polyuria), excessive thirst (polydipsia), as well as fatigue and weakness. The decrease in body weight results from heightened breakdown of structural proteins and fats due to significant insulin deficiency and dehydration in cases of pronounced hyperglycemia. Diagnosis of the disease relies on the assessment of blood glucose levels.
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