How Hormones Can Affect Your Weight Loss Efforts

Gone are the days when we could accept simple weight-loss recommendations. Experts no longer support the theory that you will lose one pound for every 3500-calorie reduction. This theory is flawed because it does not account for declining energy expenditure when you lose weight.  You carry less weight, which means you burn fewer calories. As you lose weight, you also battle biological responses that try to keep your weight stable.¹Hormones play an important role in weight loss, but they play an even bigger role in weight maintenance.¹ Your body maintains tight control over metabolism using feedback loops. Set point theory suggests that your genetic predisposition, hormones, and metabolism all work together to keep your weight in a preferred weight range.²

Restrictive diets do not work because your body protects its energy supply. You can’t reset your metabolism or your hormone levels. The best plan if you have weight gain associated with a hormonal imbalance is usually one of moderation, which includes consuming a nutritious diet, engaging in daily physical exercise, getting high-quality sleep, and relaxing to reduce stress. 

{{mid-cta}}

‍

What Are Hormones? 

Hormones are chemical messengers that are secreted by endocrine glands into your bloodstream, where they travel to target organs and have an effect.³ Hormones can bind to receptors on the surface of cells or pass through the cell membrane to the inside of the cell. Once inside a cell, hormones interact with DNA, your genetic code. Hormones stimulate your cells to increase or decrease protein production. 

Proteins produced by target cells are secreted into your bloodstream. The proteins can bind to receptors throughout your body where they can have their effect. 

How Can Hormones Affect Body Weight/Composition?

Hormones are regulated using feedback loops. The most common is a negative feedback loop. When one hormone gets too high, the nervous and endocrine systems work to bring it back towards its setpoint. Likewise, when a hormone level is too low, the nervous and endocrine systems work to bring it back up into a healthy range.

List of (Universal) Hormones That Most Directly Affect Weight Loss

The hypothalamus is a brain structure that sits at the base of the brain. It controls many bodily functions and is directly connected to the pituitary gland. The pituitary gland secretes hormones that control endocrine glands and hormones throughout the body. For this reason, it is commonly called the “master gland.”

The hypothalamus regulates appetite by integrating hormonal signals from the gastrointestinal tract, fat tissue, and the brain and uses this information to regulate your appetite and how your body uses energy. 

Hunger Hormones

An imbalance of hunger hormones can cause hunger even when you eat enough calories to support your metabolic needs. Neuropeptide Y

Neuropeptide Y is a family of gut hormones that include neuropeptide Y, peptide YY and pancreatic polypeptide. Like ghrelin and CCK, these hormones are part of the gut-brain axis, a system of hormones and nerves that enhance communication between the gut and the brain. Ghrelin stimulates neuropeptide Y release from the hypothalamus. Neuropeptide Y increases hunger. ^6,7

To maintain normal levels of neuropeptide Y:

• Add fiber to your diet to feel full longer.
• Eat a balanced diet with high-quality sources of protein.

Ghrelin

Ghrelin is a gut hormone that is produced by the stomach and in smaller amounts by the small intestine, pancreas, and brain. Ghrelin increases hunger in response to thinking about food. Sight, smell, and taste can all increase stomach motility (hunger pangs) and ghrelin release. Since even thinking about food can increase ghrelin levels, it is commonly called the “hunger hormone”. 

Ghrelin: ⁸

• Regulates food intake: increases stomach emptying and gastric acid secretion.
• Body fat: increases fat storage.
• Glucose metabolism: decreases insulin secretion and increases insulin sensitivity.
• Reward behavior: increases smell and taste sensations that make food more pleasurable.
• Growth hormone: increases growth hormone release, which stimulates muscle and bone growth. 

Ghrelin levels increase when your stomach is empty and decrease when it is full. How much ghrelin levels decrease depends on the calories you consume and the composition of the meal. In one study of nutrients and their effect on ghrelin, researchers found that:⁸

• Lipids are the least effective nutrient at suppressing ghrelin release. 
• Proteins are the most effective nutrient at suppressing ghrelin release. 
• Carbohydrates initially suppressed ghrelin, but the levels rebounded to higher than they were before the meal.
• Sham feeding (chewing but not swallowing) suppresses ghrelin, demonstrating the impact of the brain on ghrelin levels. 

Sham feeding is often used in research on hunger and digestion, though chewing gum can also be considered sham feeding. A 2018 study found that chewing stimulation, including chewing gum, reduced self-reported appetite levels in participants.⁵²

In another study, participants who thought they were consuming a high-calorie milkshake had much lower ghrelin levels after eating than people who thought they were consuming a healthier, low-calorie version.⁹ Just thinking that your meal left you full and satisfied can decrease your ghrelin levels!

Ghrelin levels are sometimes low in people with obesity, especially binge eaters, which suggests that at least in some circumstances, ghrelin levels are a consequence, not a cause of overeating.¹⁰ Fasting increases ghrelin levels, but extreme calorie restriction reduces them.⁸ In the Diabetes Remission Clinical Trial (DiRECT), researchers found that a rise in ghrelin levels after weight loss was a predictor of weight regain. Fasting ghrelin levels rose by more than 40 percent in participants who had a 10% weight loss. ¹¹ Your hormones seem to be working to restore your body weight. 

Ghrelin research has come a long way, but the link between ghrelin and appetite is still not completely understood. However, there is evidence that calorie restriction (except when taken to the extreme) and weight loss cause increased ghrelin levels, which increases hunger and makes it more difficult to maintain weight loss. 

What can you do to control ghrelin? 

• Eat a nutritious diet high in protein.
• Increase muscle mass by incorporating resistance exercises into your daily routine.⁸
• Prioritize sleep because poor sleep is associated with increased ghrelin levels.¹²
• Avoid high-fructose corn syrup as it is associated with increased ghrelin release.¹³

<p class="pro-tip"><strong>Learn about</strong><a href="/blog/sleep-and-weight-loss"> improving your sleep for weight loss</a></p>

Cortisol

Cortisol, commonly called the stress hormone, is released from your adrenal glands when your body feels the need to fight or run away. Cortisol mobilizes glucose from the liver and makes it readily available for muscle and brain cells. After mobilizing and using glucose, cortisol makes you feel hungry to restore your energy supplies.¹⁴ This response was ideal when people needed it in survival situations. 

Cortisol also:

• Suppresses inflammation
• Regulates blood sugar
• Regulates blood pressure
• Regulates metabolism

Daily stresses that stimulate cortisol release don’t burn many calories, and cortisol can cause cravings for sweet, fatty, and salty foods. Temporary increases in cortisol levels are unlikely to affect your weight, but chronically elevated cortisol may cause weight gain, along with other side effects. 

Symptoms and signs of high cortisol:

• Weight gain, especially in the abdomen and face
• Wide, purple stretch marks (stria), especially on the abdomen
• High blood sugar
• High blood pressure
• Osteoporosis
• Shoulder and hip muscle weakness

To reduce cortisol levels, try to reduce physical, mental, and psychological stress by: 

• Getting plenty of high-quality sleep 
• Staying active and making physical activity a priority
• Setting time aside for hobbies and activities you enjoy 
• Maintaining healthy relationships with friends and family
• Practicing deep breathing exercises
• Trying mindfulness and yoga 
• Learning to identify when stress is building and take a time out 
• Talking to a therapist to learn more stress-management techniques

<p class="pro-tip"><strong>Learn more about</strong><a href="/blog/what-is-cortisol"> cortisol and why it matters for health</a></p>

What Causes Imbalance in Hunger Hormones?

Conditions that can cause you to feel excessively hungry include:

• Hyperthyroidism: excess thyroid hormones increase metabolism, which increases hunger. 
• Premenstrual syndrome: appetite increases when progesterone is dominant over estrogen, cravings also increase. ⁴
• Lack of sleep: sleep deprivation increases ghrelin and decreases leptin, a combination that increases appetite.⁵
• Stress: when you are stressed, your body releases cortisol, a hormone that increases metabolic demand and therefore hunger. 
• Poor dietary choices: consuming highly processed foods, especially a high-calorie, high-sugar, and high-fat diet, increases body fat and insulin resistance. Insulin spikes after consuming sugary foods and drinks can overshoot, leaving you with low blood sugar and extreme hunger.
• Hypoglycemia or low blood sugar: hypoglycemia often happens when people have diabetes, but it can occur in healthy people as their blood sugar fluctuates.  When your blood sugar drops, your hormones respond by increasing your appetite. ghrelin, neuropeptide Y, and cortisol all stimulate hunger.

<p class="pro-tip"><strong>Learn more about </strong> <a href="/blog/hormones-metabolic-syndrome">how hormones can affect metabolic health</a>.</p>

‍

Fullness Hormones

Fullness hormones, such as leptin and cholecystokinin, oppose the activity of the hunger hormones by making you feel full and satisfied. 

Leptin

Leptin is a hormone produced by adipose tissue (fat cells) that tells your brain that you are full. The amount of leptin released is proportional to the amount of fat stored in adipose tissue as energy. Decreased leptin levels after calorie restriction and weight loss increase food-seeking and appetite. Unlike many other hormones that respond quickly to changes in metabolism, leptin acts over a longer period to help maintain your weight. Levels do not fluctuate from meal to meal. 

Since decreased leptin levels stimulate appetite, it would seem that people with obesity must have leptin levels that are too low. This is not the case. Some people with obesity actually have abnormally high leptin levels. 

Could people with obesity be resistant to leptin’s effects? This theory parallels the idea of insulin resistance in type 2 diabetes. If you are leptin resistant due to chronically high leptin levels, your brain does not receive the signal that your body has plenty of fat stores. To conserve energy, your body will slow your metabolic rate at rest, so you use fewer calories.¹⁶

People with normal or low leptin levels do not respond when given man-made leptin.¹⁵ After much trial and error, researchers have not been able to develop a drug that mimics leptin’s actions. 

While scientists search for ways to increase leptin or make leptin receptors more sensitive, your best strategies to maintain stable leptin levels are to:

• Maintain a stable weight. 
• Eat a nutritious diet. 
• Incorporate physical activity into your daily routine. 
• Get plenty of restful sleep. 
• Eat more fiber to feel full longer. 
• Consider adding fish oil as a supplement to decrease inflammation. 

<p class="pro-tip"><strong>Learn about</strong><a href="/blog/high-fiber-low-carb-foods"> the best high-fiber low-glycemic foods for weight loss</a></p>

Cholecystokinin

Cholecystokinin (CCK) is a gut hormone that signals your brain that you are full. Protein and fatty foods stimulate CCK release. 

In addition to indicating satiety, CCK has the following functions:

• Regulates fats, protein, and carbohydrate digestion. 
• Causes the gallbladder to release bile, which helps digest fats. 
• Regulates how fast your stomach empties. 
• Increases leptin release. 

Obesity decreases CCKs effects on the brain, which means that people with obesity do not get the same sense of fullness and satiety that they would with normal CCK sensitivity.¹⁷ While research about CCK and its relationship to appetite and weight gain is spotty, try these strategies to increase CCK sensitivity:

• Increase your fiber intake to stimulate stomach receptors that indicate fullness.¹⁸
• Drink plenty of water to stimulate stomach receptors that indicate fullness.
• Increase protein intake to stimulate CCK release.
• Increase fat intake to stimulate CCK release.

<p class="pro-tip"><strong>Learn more about</strong><a href="/blog/signs-of-hunger"> hunger signals and true hunger</a></p>

Hormones That Regulate Blood Sugar

Epinephrine, cortisol, and growth hormone all help maintain blood glucose levels. Glucagon and insulin regulate blood glucose. Glucagon increases blood glucose and insulin decreases it. 

Insulin

Insulin is a hormone produced by beta cells in the pancreas. Insulin is secreted into the bloodstream when blood sugar increases after a meal. Insulin ushers glucose from the blood into body cells, where it can be used for energy. Excess glucose that is not needed for energy is converted into glycogen and stored in the muscles and liver. When glycogen stores are full, any excess glucose is stored in adipose cells. 

When your blood glucose spikes after a meal, your insulin levels will also spike to quickly remove glucose from your bloodstream. Unfortunately, your blood sugar can fall too much, which makes you feel hungry. As this cycle is repeated and excess calories are stored as fat, your body becomes less sensitive to insulin, a condition called insulin resistance. Insulin resistance makes it harder for your body to move glucose into muscle and fat cells.¹⁹ Initially, your pancreas will compensate for insulin resistance by producing more insulin. Chronically high insulin levels mean that your body holds on to energy instead of burning through glycogen and fat stores. 

You can reverse insulin resistance by: 

• Increasing physical activity: Make time for at least 30 minutes of exercise each day. Any type of exercise will improve insulin sensitivity. Aerobic exercise will also improve cardiovascular health and resistance exercise will increase muscle mass.^20,21 
• Eating nutritious foods: Well-balanced nutritious meals can help minimize insulin spikes and help you lose excess weight, which can help improve insulin sensitivity.²² 

<p class="pro-tip"><strong>Learn about</strong><a href="/blog/control-blood-sugar-spikes-after-meals"> controlling blood sugar spikes after meals</a></p>

Glucagon

Pancreatic alpha cells secrete glucagon. While insulin is secreted to keep blood glucose from increasing too much, glucagon helps keep blood glucose from dropping too low, a condition called hypoglycemia. 

Glucagon:²³

• Signals your liver to break down glycogen into its component glucose units so they can be used for energy.  
• Prevents your liver from storing more glucose as glycogen.
• Converts other nutrients, such as amino acids, pyruvate, and lactate, into glucose. This process is called gluconeogenesis.

A high glucagon to insulin ratio also increases adipose (fat) tissue breakdown, which can lead to weight loss. Medications that stimulate gut hormones that modulate glucagon levels are targets for many weight management drugs. New drugs activate both the glucagon and incretin receptor agonists (glucagon-like peptide-1), which increase fat breakdown, slow stomach emptying, and reduce hunger, which leads to weight loss.^24,25

<p class="pro-tip"><strong>Learn about</strong><a href="/blog/medications-weight-gain"> medications that can cause weight gain</a></p>

Glucagon and insulin are counter-regulatory hormones. The best way to increase glucagon is to prevent insulin spikes. Try these strategies to reduce insulin spikes: 

• Meditate to reduce stress and cortisol release. 
• Pair carbohydrates with proteins. 
• Avoid refined, highly processed carbohydrates. 
• Exercise to improve insulin sensitivity. 
• Eat more fiber to slow nutrient absorption. 
• Drink more water to avoid dehydration. 

Sex Hormones

Sex hormones affect both fat mass and muscle mass. Therefore, they can impact your metabolic rate and calorie burn. 

Testosterone

Both men and women have testosterone, but levels are much higher in men. Testosterone production begins at puberty and declines by about 1% each year, starting around age 30.²⁶ Testosterone helps maintain and support:²⁷

• Muscle mass
• Muscle strength
• Fat distribution
• Bone density, thickness, and strength
• Libido
• Red blood cell production
• Body and facial hair

As testosterone levels decline, your body composition changes, muscle mass decreases and fat mass increases, which makes it more difficult to maintain your weight. Researchers found that restoring testosterone in men with testosterone deficiency resulted in better glucose utilization and increased fat burning.²⁸Boost testosterone naturally by: 

• Maintaining a healthy weight: Fat cells contain high levels of aromatase enzyme. This enzyme converts testosterone to estrogen, which can reduce testosterone levels. 
• Exercise regularly: Increasing physical activity, especially resistance exercise, can increase muscle mass and reduce fat mass. In one study, researchers found that progressively increasing resistance exercise can restore muscle testosterone levels.²⁹ Another study showed that resistance exercise must be continued or gains in testosterone will be lost in about four weeks.³⁰  Increases in physical activity seem to have a bigger impact on testosterone levels than other lifestyle changes, such as reducing calories. ³¹
• Get your vitamin D: Whether you go outdoors for 20 minutes of sunshine or take a vitamin D supplement, getting the recommended daily amount of vitamin D can help restore testosterone levels. ³²
• Get plenty of restful sleep: In a study that measured morning testosterone levels in sleep-deprived older men, quality and length of sleep predicted free and total testosterone levels in the morning. The authors acknowledge more research is needed, as they used a small sample size. Since sleep quality influences many hormones, try to get 7 to 8 hours of high-quality sleep each night.³³ 
• Drink alcohol only in moderation: Researchers found that alcohol affected testosterone levels only when very large amounts were consumed (greater than 40 grams/day). ³⁴

<p class="pro-tip"><strong>Learn more about</strong><a href="/blog/alcohol-weight-gain"> alcohol and weight gain</a></p>

Dehydroepiandrosterone

Dehydroepiandrosterone (DHEA) is produced by the adrenal glands, which are small glands right above the kidneys. DHEA is a precursor to androgens and estrogens. DHEA levels peak in your mid-20s and then decline after age 25. When researchers gave participants enough DHEA to raise their levels equal to young adults, they noted:³⁵

• Increases in testosterone levels in women, but not in men. 
• Increases in estradiol (estrogen) in both men and women. 
• Small but significant increases in insulin growth factor-1 concentrations. 
• Significant decreases in abdominal fat over six months. 
• A significant increase in insulin sensitivity. 

While these results seem promising for weight loss, other studies have shown that DHEA levels increase, but there were no weight loss or insulin sensitivity benefits to supplementing with DHEA.^36-38

Estradiol/estrogen and Progesterone

Progesterone is a hormone secreted by the ovaries after ovulation. Progesterone prepares the uterus for pregnancy and supports the pregnancy if a fertilized egg implants in the uterus. 

Estradiol is a sex hormone that is produced in the ovaries and testes. It regulates the female reproductive system and influences the endocrine, skeletal, adipose, and cardiovascular systems.³⁹ Estrogen promotes energy storage as fat (but only in certain locations), decreases hunger, and increases water and salt retention.⁴⁰ Progesterone increases hunger and increases energy usage. As long as estrogen and progesterone levels are balanced, the fat storage effects of estrogen are balanced by the energy-burning effects of progesterone. ⁴¹

Estrogen declines after menopause are associated with an increase in total body fat, especially abdominal fat, and a decrease in lean body mass, so weight is not affected. However, a decrease in muscle mass means a decrease in metabolic rate, which means fewer calories are needed to sustain bodily functions.

Weight gain post menopause is thought to be related to decreased muscle mass associated with aging, decreases in physical activity, and sleep disturbances.⁴² Other experts suggest that estrogen inhibits hunger signals and when estrogen levels decrease during perimenopause, women experience more intense hunger, which leads to weight gain.⁴³ Increased fat mass, especially abdominal fat, is associated with high blood pressure, cardiovascular disease, and diabetes. 

<p class="pro-tip">Related: Aging, Blood Sugar, and Metabolic Health</p>

Many women opt for hormone replacement therapy or bioidentical hormones to compensate for decreasing estrogen. Bioidentical hormone therapy can describe chemically made hormones that are identical to human hormones or custom-compounded hormones. 

Estrogen and progesterone combinations may vary when used for hormone replacement and oral contraception, but they are both used to replace estrogen, progesterone, or both. 

Today, estrogen and progesterone in hormone replacement and contraception are both given in much smaller doses than when contraceptive pills were developed in the 1950s. A meta-analysis of 49 studies found no real evidence to suggest a link between estrogen-progesterone contraceptives and weight gain.⁴⁴ To manage your weight through menopause:  

• Get high-quality sleep: Sleep disturbances are common around menopause. Try to get 7 to 8 hours of restful sleep.⁴⁵
• Build more muscle: Resistance exercise can build muscle and improve insulin sensitivity. 
• Choose healthy snacks: Researchers found that ghrelin levels increase after exercise, but only in women. If women aren’t careful, hunger can drive them to choose high-calorie snacks that sabotage their weight-loss efforts.⁴⁶
• Eat mindfully: Your environment strongly influences food choices. It is easy to overeat while distracted by technology while eating, or when unhealthy food choices are visible and easy to access. 
• Lower your stress: Stress increases cortisol release. When demands for cortisol are high, more pregnenolone is converted into cortisol, which leaves less to make estrogen and testosterone. 
• Choose a well-balanced, nutritious diet: A well-balanced diet can help with weight management and reduce the risk of chronic diseases. 
• Consider phytoestrogen: Foods high in phytoestrogen, especially soybean, may help alleviate menopausal symptoms and promote better muscle and bone health.⁴³
• Reduce your exposure to endocrine disruptors: Endocrine disruptors are chemicals that interfere with normal hormone activity such as bisphenol A, dioxins, and phthalates.  

How Hormones Affect Weight Loss for Women

Women have a different fat distribution and a higher percentage of body fat than men. Premenopausal women store fat in the buttocks and upper legs, whereas men and postmenopausal women store fat in the abdomen. Men typically have a higher muscle to total body weight ratio due to having more testosterone.⁴⁷ These differences are largely due to hormonal differences between men and women, which can make weight loss for women a slightly more challenging process than it is for men. 

Other Hormones

Growth hormone and thyroid hormone regulate metabolism and body composition. 

Thyroid hormones/ Thyroxine

Thyroid hormone controls metabolism and is frequently referred to as the fat-burning hormone. When thyroid hormone is too high, metabolism and calorie burn increase. When thyroid hormone is too low, metabolism slows. 

When the thyroid gland does not produce enough thyroid hormone and calorie intake stays the same, you will gain weight. 

Adipose tissue (fat cells) secrete chemicals such as leptin, that influence thyroid hormone production. Leptin binds to receptors in the hypothalamus and increases thyrotropin-releasing hormone (TRH) which increases thyroid-stimulating hormone (TSH) which increases thyroid hormone and therefore increases metabolism. When calories are restricted, leptin levels decrease and so does thyroid function. This suggests that this relationship is complicated and likely involves many hormones.⁴⁸

Growth Hormone

Growth hormone is produced by the pituitary gland and supports longitudinal growth throughout childhood and adolescents. In adulthood, growth hormone has an important role in maintaining a healthy body composition. Growth hormone, like testosterone, steadily declines with aging.⁴⁹

Symptoms associated with growth hormone decline include: 

• Decreased muscle mass 
• Decreased muscle strength 
• Increased abdominal fat 
• Increased risk of metabolic syndrome 
• Reduced stamina 

Steps you can take to naturally increase growth hormone include: 

• Lose excess pounds: increased abdominal fat can reduce natural growth hormone release. ⁵⁰
• Reduce your sugar intake. 
• Exercise regularly and for an added boost in growth hormone, try high-intensity interval training.⁵¹
• Get plenty of high-quality sleep. 

When to Talk to a Doctor About Hormone Levels and Weight Loss Efforts

The endocrine and nervous systems work hand in hand to keep your body’s internal environment stable, whether it is body temperature, heart rate, blood pressure, or body weight. Sometimes hormones become unbalanced. When this happens, depending on the hormone, you may experience symptoms. 

If you think weight gain is hormonally related, an evaluation by an endocrinologist can help you sort out what is causing your symptoms. Thyroid imbalance, declining estrogen, elevated cortisol,  and insulin resistance, are just some of the potential hormone imbalances that can cause weight gain. 

After taking a complete medical history and doing a physical exam, your endocrinologist will probably request blood and urine samples to check your hormone levels. Your treatment choices will depend on the hormonal imbalance. 

Addressing hormone-related weight gain now can decrease your risk for type 2 diabetes, mood disturbances, infertility, cardiovascular disease, and frailty. Hormonal weight gain is treatable if an underlying cause can be identified. In many cases, a single hormone abnormality is not the cause of weight gain. There are many reasons for weight gain. In these cases, improving your overall health is the best treatment option.