While an unhealthy diet and a sedentary lifestyle are the most common causes of obesity, hormonal imbalances can also contribute significantly towards weight gain. Basically, hormones are chemical messengers that help regulate different functions in your body, including metabolism, hunger and satiety.
Dr K Padmanabhan, MD, general medicine and diabetologist, Fortis Hospital, Vadapalani, Chennai, says, “Abnormal levels of hormones such as cortisol, insulin, leptin and ghrelin can disrupt weight control mechanisms and contribute to obesity.” During hunger, the ghrelin levels increase and leptin levels decrease. The opposite is true during satiety,” he adds.
Some hormones that have a direct and indirect effect on your body weight and metabolism include:
Leptin, an appetite suppressant hormone produced by fat cells, helps regulate appetite and metabolism. It sends signals to the brain when you eat enough food or feel satisfied. However, people with obesity tend to have leptin resistance which causes increased hunger, resulting in over-eating and further weight gain, explains Dr Manoj Khandelwal, consultant, endocrinology, Fortis Escorts Hospital, Jaipur.
Ghrelin, often called a hunger hormone, is secreted by the gastrointestinal tract. It stimulates and increases the appetite. It also increases fat accumulation, mostly in the abdomen, says Dr Padmanabhan. When ghrelin levels are high, we feel hungry and tend to eat more.
Generally, ghrelin levels rise before meals and fall after eating. However, in people with obesity, the levels tend to have less suppression postprandial (after a meal). This causes an increase in appetite and makes them eat more, which leads to overeating, explains Dr Khandelwal.
“High cortisol levels are associated with weight gain and obesity,” says Dr Khandelwal. Cortisol is responsible for regulating the body’s stress response.
Dr Padmanabhan says, “In people with obesity, the cortisol levels can be abnormally high which can lead to increased fat storage, especially in the abdominal area.” Also, high cortisol levels alter the appetite, further elevating the craving for food, especially the high-fat and high-sugar ones,” he adds.
4. Growth hormone
Growth hormone secreted by the pituitary gland is responsible for influencing an individual’s height and muscle growth. Increased growth hormone levels can lead to high metabolism. However, growth hormone levels in obese people are lower than those of normal weight, leading to a low metabolic rate. This results in burning fewer calories and more fat getting stored in the body, eventually leading to weight gain, says Dr Khandelwal.
Insulin, secreted by the pancreatic beta cells, is responsible for glucose metabolism in our body. “In people with obesity, the body becomes resistant to insulin. This leads to an overproduction of the hormone, elevated blood sugar levels and increased fat storage,” says Dr Khandelwal. Insulin resistance is the main reason for type 2 diabetes, which has emerged as a major health risk across the globe. According to a study published in the journal Nutrition & Metabolism, a low-carbohydrate diet prevents metabolic syndrome and associated insulin resistance.
6. Estrogen and androgen (sex hormones)
Sex hormones like estrogen and androgen play an important role in body fat distribution. Distribution of fat, especially around the abdomen, puts one at risk for various conditions like type 2 diabetes (which is closely linked with obesity).
Dr Khandelwal adds that men tend to have high levels of fat around their abdomen (apple-shaped), while women tend to have excess fat below the waistline, around the hips and thighs (pear-shaped).
Low estrogen levels are often attributed as one of the reasons for weight gain and related co-morbidities like diabetes and heart issues in women after menopause. High levels of androgen (male sex hormone) also tend to increase fat deposition around the abdomen.
7. Thyroid hormone
Thyroid hormones, which are secreted by the thyroid gland, are important for regulating weight. “Thyroid hormone is mainly responsible for increasing our metabolism. Hypothyroidism [low thyroid level] can lead to a slower metabolism, weight gain and a higher body-mass index [BMI],” says Dr Khandelwal.
Managing hormonal imbalance
Imbalances in hormones, which play a critical role in weight regulation, can contribute to weight gain and obesity. Experts suggest a balanced diet for maintaining an ideal body weight. “People with a BMI greater than 25 should consume around 1200 calories per day,” says Dr Khandelwal.
However, he adds that someone who works out should consume more calories. Adding a simple exercise routine such as a 30-minute brisk walk, swimming or cycling also helps to control hormonal imbalances.
- Hormonal imbalances can contribute to weight gain and obesity.
- Lifestyle modifications like having a balanced diet, getting enough sleep, managing stress and exercising are some ways to manage and prevent obesity.