The body retains more water in the initial stages of a diet, especially one high in carbohydrates. This process is directly linked to glycogen management, which can lead to higher numbers on the scale. Again, it’s important to note that this should not be seen as a failure.
Causes
Obesity is mainly caused by increased body fat as we age, while lean body mass decreases. It can happen through hypertrophy, which indicates a boost in the size of fat cells, or hyperplasia, which means an increase in fat cells. Both processes can occur simultaneously, but it’s important to note that the increase in fat cell number is irreversible and can continue indefinitely.
In adults, fat cells tend to increase in dimension rather than number. When there’s an imbalance between the energy obtained from food (energy supply) and the energy expended, obesity can develop.
The placement of adipose tissue is also significant. There’s central (android) obesity, which is located around the abdomen and can lead to cardiovascular diseases and type 2 diabetes. This type of obesity is associated with boosted resistance to insulin. The other type, gluteal-femoral obesity, is more common in women and involves the accumulation of fat around the buttocks and thighs.
Obesity-related Diseases
The belief that weight gain is associated with poor nutrition and lack of physical activity has been confirmed. However, weight gain is not always associated with a metabolic disorder and an inappropriate lifestyle. Other factors, such as some diseases, also affect obesity.
Some diseases and conditions cause uncontrolled weight gain. Sometimes, it is related to medications that increase appetite, hormonal changes, or accompanying stress.
Conditions causing weight gain:
- Hormonal disorders (e.g., polycystic ovary syndrome)
- Menopause
- Hypothyroidism
- Type 2 diabetes
- Genetic diseases (Cushing’s syndrome, Down’s syndrome, Turner’s syndrome)
- Stress
- Growth hormone deficiency
- Sleep problems
Polycystic Ovary Syndrome
Polycystic ovary syndrome is a condition caused by hormonal changes, with main symptoms such as fat accumulation around the abdomen, menstrual irregularities, migraines, and excessive facial hair.
Hormonal Changes
Menstrual irregularities and hormonal changes that lead to a complete cessation of the menstrual cycle can result in weight gain due to estrogen deficiency and a slower metabolism, causing fat to accumulate around the abdomen, waist, arms, and thighs.
Hypothyroidism
Hypothyroidism, which includes the accumulation of fat tissue and subsequent weight gain, is caused by hormone deficiency and a slow metabolism. Treatment by an endocrinologist and dietician can help restore proper metabolism and reduce weight.
Type 2 Diabetes
Type 2 diabetes and obesity have a bidirectional relationship, with being overweight contributing to the disease and vice versa. Insufficient insulin in type 2 diabetes patients is responsible for improper metabolism, accumulating fat tissue.
Genetic Disorders
Genetic disorders such as Cushing’s syndrome, Carpenter’s syndrome, Bardet-Biedl syndrome, Prader-Willi syndrome, and Down syndrome can cause obesity due to fat accumulation.
Stress
Excessive stress can increase appetite and produce cortisol and adrenaline, which in turn lead to fat accumulation, particularly around the abdomen, back, and neck. Raised cortisol levels may result in metabolic syndrome and abdominal obesity.
Hypopituitarism
Hypopituitarism, which causes a decrease in growth hormone synthesis, can lead to the breakdown of muscle proteins and subsequent weight gain.
Overweight And Obesity Causes Other Diseases
It is not only diseases that cause excess body weight. The opposite can happen when overweight and obesity are responsible for the occurrence of diseases and ailments. Here are some examples:
- Stroke
- Heart disease
- Hypertension
- Cancer
- Gallstones
So, if diseases result from being overweight, they should be prevented as soon as possible before they cause more health problems.
Pregnancy
Pregnancy, especially its further development, i.e., the second and third trimesters, causes rapid weight gain. However, this is a physiologically justified condition for the development of the fetus. Therefore, a rational increase in body weight in women expecting a child is natural.

Genetic Conditions
The genes we inherit from our ancestors will also be a factor that can be treated as one of the causes of weight gain. However, despite genetic predispositions, a so-called releasing factor will always have to occur, and these are most often bad eating habits. Therefore, the main reasons for weight gain are an incorrect diet and lack of physical activity.
Improper Diet
The causes of weight gain, in most cases, come down to consuming excess calories. It will also be related to the quality of food consumed and an improperly balanced diet. Too many simple sugars and fats, usually from sweet and salty snacks or carbonated drinks, are empty calories that do not nourish the body. We reach for them most often in crises, when we are hungry and do not have access to a nutritious meal. Therefore, it is worth planning your diet to defend yourself from such circumstances.
Here are some tips on controlling the calories you consume.
Calculate Your Energy Needs
First, you should estimate how many calories you should ingest. You can use the available calorie calculator to indicate the daily energy requirement. The most common reason for gaining weight is consuming more calories than our body needs.
Balance Your Diet In Terms Of Macronutrients
Insufficient amounts of high-quality protein and healthy fats, in contrast to a high intake of simple carbohydrates, contribute to rapid weight gain. High-quality protein and unsaturated fatty acids provide the body with the necessary nutrients and affect the feeling of satiety.
Avoid Simple Sugars In Your Diet
The main cause of weight gain is the excessive consumption of simple sugars, which we most often consume as sweet and salty snacks. Bars, candies, cookies, and yeast rolls provide a quick boost of energy, but after eating them, the feeling of hunger quickly returns, which prompts you to reach for another snack.
Give Up Fast Food
Give up snacks and fast food products. They are a source of empty calories. They include an enormous quantity of fat, carbohydrates, and salt, but at the same time, little fiber, vitamins, and minerals. These foods provide calories but only satisfy hunger for a moment. The deficiency of a feeling of satiety results from the fact that these foods include a nominal amount of dietary fiber. Therefore, you should eat products rich in vitamins, minerals, and fiber, i.e., vegetables, fruit, bran, wheat germ, and nuts.
Choose The Right Culinary Techniques
The best culinary methods include:
- Cooking in a small amount of water
- Steaming
- Baking in the oven or a combination cooker
- Grilling
- Baking in aluminum foil or parchment paper
- Stewing without adding fat
In addition to carefully selecting foods and following the principles of proper nutrition, the above advice should be supplemented with increased physical activity, which is an excellent support for healthy weight loss.
Medications
In people with obesity, excess calories taken with food accumulate in fat cells but are not converted into energy. However, certain medications have a side effect of weight gain. These are mainly glucocorticosteroids, popularly known as steroids. But other preparations can cause weight gain. Learn about medications that can cause you to gain weight after taking them.
Steroids
When glucocorticosteroids are given in replacement doses to patients with adrenal insufficiency, they may experience weight gain, which is a desired effect. Adrenal insufficiency often leads to excessive weight loss due to a lack of appetite. Medication helps these patients return to their normal weight by providing the same dose of glucocorticoid that the adrenal cortex naturally secretes.
On the other hand, patients with some conditions often require high doses of anti-inflammatory steroids, which can lead to weight gain as a side effect. In such cases, fat tissue tends to accumulate.
Taking small doses of steroids, you do not have to gain weight at all. But if you feel better after taking the medication, you have a better appetite and eat more. The result is weight gain. It is not a complication of the treatment but the result of providing the body with too many calories about the demand.
It is also worth remembering that diseases requiring steroid treatment reduce physical fitness. They cause you to avoid physical exercise, which contributes to excess weight development.
Allergy Medicines
People taking antihistamines may believe that the treatment causes them to gain weight, but the reality is more straightforward. These drugs have a minor effect on the central nervous system and the appetite center, making you hungrier. Weight gain is likely if you don’t control your hunger and start eating more.

Hypothyroidism And Hyperthyroidism
Thyroid disorders can also impact body weight. With hyperthyroidism, you lose weight, and with hypothyroidism, you gain weight. The drug administered in such cases is thyroxine – a hormone that accelerates metabolism. By taking it, the patient should lose weight.
It is challenging to explain overweight or obesity by taking thyroxine. With balanced hypothyroidism and proper treatment, maintaining the right body weight is simple. If you are overweight, there is only one reason – too much food about the body’s needs.
The problem of overweight looks different in the case of treatment for hyperthyroidism. In people with this condition, the metabolism is fast, which helps them lose weight. However, when the medication stabilizes the metabolism, weight gain can occur if eating habits remain unchanged. It is standard in female patients who are accustomed to eating more during the illness, and with the metabolism back to normal, excess food can lead to weight gain.
Hormonal Therapies
In modern contraceptive pills, the doses of estrogens are so low that their concentration in the blood serum is close to the natural one, so it should not affect weight gain.
On the other hand, other hormones contained in the pills – progestogens – can have a slightly sleep-inducing effect and lower mood. For some women, the way to improve their mood is to eat, which is why they are overweight. In addition, when using contraceptive pills, especially at the beginning, sometimes food cravings appear, which are similar to those during pregnancy.
It is similar to hormone therapy. During perimenopause, the concentration of estrogen in the blood decreases, and hormone therapy replenishes its deficiencies. Thanks to this, insulin and glucose management improves; consequently, weight loss can be expected. However, we reduce the caloric value of meals or increase physical activity because, with age, the body uses less energy.
The mechanism is the same as in the previous cases – it is not the drug that makes you fat, but the excess food.
Diabetes Medications
For people with type 2 diabetes, maintaining a proper weight is an important element of treating the underlying disease. The higher the body weight, the greater the body’s demand for insulin and the risk of lack of control throughout the disease.
In addition, it is worth remembering that insulin itself fattens. In the initial period of type 2 diabetes, the body has a very high level of insulin, which, however, does not function properly. Drugs administered to the patient can either increase insulin secretion or improve its action. Drugs that increase insulin secretion promote weight gain, which is why they are not beneficial at the beginning of treatment.
Similarly, when the insulin dose is raised in a patient using insulin, the body reacts. Medications from the biguanide group cause weight loss. That’s why modern diabetes treatment often begins with m*******n, which also helps reduce body weight.
Antidepressants
Many antidepressants do not increase appetite; in fact, some reduce it. However, some individuals may gain weight during depressive episodes due to increased appetite, often referred to as eating stress. During the low mood phase, they reject food and quickly lose weight.
If such a person is given antidepressants that increase appetite, the patient returns to normal weight, which is beneficial for their body. In the case of antidepressant treatment, it is not the medication that affects weight gain but rather the changes in mood and the resulting need to relieve sadness with food.
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