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ASK THE NUTRITIONIST: Are my hormones making me fat?

Nonie De Long explains the roles hormones can play in weight loss and gain

Dear Readers, today’s question from Celine is one I have heard frequently over the years, usually from middle-aged women, but sometimes from parents of teens suffering from obesity. In menopausal women it changes slightly from a question, “Are my hormones making me fat?” to an indictment, “Menopause made me fat.” So let’s unpack what is known about the role of hormones and weight gain.

What Are Hormones?

First, let’s start with the basics. What exactly are hormones and what do they do? Hormones are chemical messengers throughout the body. They are secreted into the bloodstream to travel to other organs and tissues where they have an impact. Think of them as master switches in a sense, regulating how the body does what it does. For example, the thyroid regulates metabolism, appetite, and temperature. There are many types of hormones that impact various bodily functions, including: development and growth, metabolism, reproductive health (including sex and gender hormones), cognitive function, mood, and maintenance of thirst, appetite, and body temperature.

It used to be thought that hormones are secreted only by the endocrine glands in the body. These are the pituitary, the pineal, the thymus, the adrenals, the pancreas, the testes, and the ovaries. But now research has shown that several organs can also secrete hormones, including the heart, the lungs, the kidneys, the GI tract, the placenta, the skin, and fat cells.

Yes, fat cells also emit hormones.

The hormones released by the various organs/glands are microscopic in amount. Yet, they bring about incredible changes in the body. Even a very slight deviation can have an impact and lead to a disease state.

Readers, I want you to take a look again at the list of the body functions that are impacted by hormones and consider the prevalent diseases of today. It seems to me there is a huge overlap. Hormonal health and the toxins that impact these needs to be a bigger conversation! If that is a rabbit hole you would like to go down, here is a place to get started. Now on to how hormones affect our appetite and weight.

Appetite and Hormones:

Clearly there is a link between appetite and hormones. Women are able to observe this with the changes in their menstrual cycles and during pregnancy. The follicular phase of a woman’s cycle, which starts with menstruation and ends with ovulation, has been documented to lower appetite, while the luteal phase, which begins just after the egg is released, increases appetite. This is why women often reach for snacks or have intense cravings just before their period hits. Just after that time, the cravings and appetite die down again.

In research on both humans and animals, the difference in calories between the two phases was noted as ranging between 200-600 calories. These appetite changes did not occur when women no longer ovulate. (source)

Aside from these, some of the key hormones that are known to affect appetite are:

  • Ghrelin
  • Leptin
  • Insulin
  • Thyroid hormones (TSH, T3, T4)
  • Cortisol


Ghrelin is a hormone that activates growth hormone and appetite. It’s made in the gut (stomach and intestines) and sends signals to the central nervous system and brain. It lets us know when the body needs food for energy by stimulating appetite. In addition it increases fat deposition, stimulates growth, and more. Related to weight gain, we know it impacts insulin secretion and glucose and fat metabolism, GI motility, blood pressure and heart rate.

It’s also released more when we are stressed, which helps us understand why some people eat more when stressed. It works together with leptin, the next hormone we’ll talk about, and insulin, which we’ll talk about later. Studies have found that high protein meals help reduce ghrelin levels and create longer satiety to facilitate weight loss.

Ghrelin decreases after eating, when the satiety hormone, leptin, steps in.


Leptin can be considered the opposite of ghrelin. This hormone is created by the fat cells and tells the body it’s had enough to eat, it’s time to take a break. Newer research suggestions t can be resistant in obese people, the same as insulin can be. The two are thought to be closely connected. Eating meals that contain healthy fats have been shown to induce leptin signaling and meals that are chronically high in glucose can shut it down. In fact, pediatric endocrinologist, Dr. Robert Lustig, has stated that fructose consumption has been shown to inhibit leptin signalling.


Insulin is the hormone that regulates blood sugar and deposits extra food energy into fat cells to be stored for later use. When it’s present, the body cannot burn stored fat. Over time, if it’s signalled too much, it can become resistant to being sequestered. This is called insulin resistance and when this goes too far we are diagnosed with type 2 diabetes. The medical model is to replace the body’s insulin with extra insulin so we can continue to store food as energy (fat), but this does nothing to address the roots of the disorder or reverse it. Weight from insulin resistance is stored around the middle, even in thin people. For the best advice on how to reverse this disorder through dietary interventions, go to Nobody has more information or better information on insulin resistance.

Thyroid Hormones

Thyroid hormones stimulate or down regulate metabolism and energy. They have a profound impact on how energized or tired we feel. Often our physicians test for thyroid disorders during our physical exam blood workup, but this only tests for clear cases of extreme dysfunction. Many women experience the symptoms of thyroid dysfunction before it shows up as problematic on the normal tests.

In these cases it’s imperative to see a nutritionist or naturopath or functional medicine physician who specializes in thyroid disorders to get a full thyroid assessment, which includes different tests and symptomatology, to rule out any dysfunction. Key indicators that the thyroid is off are feeling cold or hot all the time, losing hair rapidly, being unable to think clearly or mobilize normal energy, a large lump in the middle of the throat, or losing weight very quickly.

Thyroid weight gain is often in the hips, with a slender waist. Thyroid weight loss is often accompanied by protruding eyes. For a full set of symptoms to look for, go here.


Cortisol is considered ‘the stress hormone’ because it’s released during times of perceived threat to help us mobilize quickly away from the source of danger. It’s made by the adrenal glands, which sit on top of our kidneys. Think of this as our fight or flight hormone. It temporarily increases strength and energy. It’s also secreted to help us wake up in the morning and to help us when we do intense exercise. But what many people don’t know is that this hormone slows down blood flow to the organs when it increases blood flow to the limbs and, as a result, it can greatly impact our ability to gain or lose weight.

When we have too much cortisol we can suffer weight gain in the abdomen and face, thin skin that doesn’t heal properly, acne, and facial hair with irregular menstrual periods for women. Alternately, when we don’t have enough cortisol we can suffer fatigue, nausea, vomiting, eating disorders, weight loss, muscle weakness, and pain in the abdomen.

Additionally, chronic stress can cause symptoms like inflammation, brain fog, high cholesterol, diabetes, ulcers, allergies, asthma, and energy and sleeping problems. I see this the most in women of middle age who have suffered some trauma and are avid fitness buffs. They have depleted their bodies completely and the exercise is exacerbating their symptoms. No matter how much they exercise, they can’t get rid of the tummy.

Testing the cortisol levels is an important consideration when stress levels have been too high for too long or when a person exhibits symptoms that suggest there might be dysfunction. In addition, removing intense exercise and adopting a therapeutic diet can help normalize the stress response in the body.

As you can see, hormones play a significant role in appetite and energy production, as well as fat deposition, growth, metabolic rate, and satiety. If any one hormone is out of balance, it often follows that others are impacted. This is when a holistic hormonal specialist is advised.

Thank you for writing in, Celine. As always, readers can submit their health related questions to and can find me online at


Nonie Nutritionista