8 Causes of Stubborn Weight Loss


Do you struggle losing weight or maintaining weight loss? Are you sick and tired of watching what you eat, exercising profusely and then stepping on the scales to find the numbers haven’t budged? Why, you ask, if you work out like a tennis champion five days a week and eat like a bird, do you still have problems losing weight?

There is a well-known equation: calories in < calories out= weight loss. This over-simplified equation is adopted by many weight loss programs and can actually be potentially harmful for a lot of people. At first, these weight loss programs may cause rapid weight loss however, often this is not from the loss of fat but from the breakdown of your cell structures, organ tissue, bone and muscle. During this process, your body uses up vital proteins and fats- which are not being replaced with good nutrition- just to stay alive. Over time, your body reaches a plateau, where you are exhausted. At this point, eating even less and exercising even more intensely can actually result in gaining more weight back than was lost. This is because your body tends to default towards conservation and conserves resources due to deprivation.

When it comes to stubborn weight loss, the best thing you can do rather than restrict your calories even more, is work with a healthcare professional to determine what are the underlying reasons you’re struggling to lose weight. When it comes to weight loss, one size definitely does not fit all. There may be various factors involved including:

  1. Food sensitivities and inflammation

 One of the major reasons people find it hard to lose weight is due to undiagnosed food sensitivities and inflammation. Food intolerances lead to the production of IgG antibodies, which activate the immune system when you eat an offending food. This leads to inflammation in the body which, in turn, impairs the brain’s ability to receive leptin’s appetite-supressing communications. Leptin is the hormone responsible for sending signals to the brain to supress appetite and speed up metabolism, assisting with weight loss. Inflammation also increases water retention and bloating, making you less likely to want to engage in physical activity.


  1. Poor liver function and toxic chemical exposure

 Poor liver function prevents weight loss as the liver is the body’s primary fat metaboliser. If the liver is not functioning properly, it can lead to the accumulation of fat in your liver. This in turn can decrease your body’s normal responses to insulin (insulin resistance) which is produced in your pancreas and helps control the amount of glucose or sugar in your bloodstream. Some symptoms of poor liver function include itchy skin, liver spots on the skin, hypertension, excessive sweating and unpleasant body odour, chronic fatigue, depression or irritability, abdominal pain, poor tolerance to fatty foods, bad breath, pale stools, nausea and hormonal imbalances.

The liver is also responsible for processing and eliminating toxins that you’re exposed to on a daily basis including pesticides, fungicides and heavy metals. When the ability of your liver to remove toxins is compromised, your body stores fat to protect your vital organs from exposure.  The only way to shed this fat is to rid yourself of toxins via detoxification.


  1. Insulin imbalance and PCOS

 Insulin imbalance is one of the leading causes of stubborn weight loss. Insulin is the hormone that unlocks the door to your cells to allow glucose into them. Insulin resistance occurs when the body is forced to release far too much insulin due to high levels of glucose in your blood stream. Your cells are unable to absorb the extra blood glucose your body keeps generating from the food you eat and your liver converts the glucose into fat. Insulin imbalance can lead to Type 2 diabetes and obesity. It is also an underlying driver of Polycystic Ovarian syndrome (PCOS) where the high levels of insulin increase the production of androgens (male hormones) which can lead to irregular periods, male pattern hair growth, acne and weight gain. With PCOS, the hormones that regulate satiety and feelings of fullness are also not working properly so you’re more likely to feel hungry even when your body doesn’t need food.


  1. High stress

Stress can make it not only harder for you to lose weight but can also make you gain weight in the first place. Cortisol, your primary stress hormone, is an adrenal hormone that helps you run faster and pumps fuel into your bloodstream for quick energy. When you are in this “fight or flight” state and your body needs to prioritise the stressor over its normal functions, cortisol shuts down digestion and slows metabolism. If left unchecked in periods of prolonged stress, high levels of cortisol can lead to high blood sugar, increased belly fat, high blood pressure, high cholesterol and muscle loss as it causes the body to “store and reserve” resources for a later time when you may need them. High cortisol also increases your appetite making you reach for sweet, high calorific foods and can impair your ability to produce enzymes necessary for the breakdown and absorption of nutrients. Stress also influences sleep quality and duration as well as levels of insulin and glucose.


  1. Thyroid dysfunction

 Hypothyroidism, a condition where the thyroid does not produce enough thyroid hormone, is characterised by unexplained weight gain and/or difficulty losing weight. Thyroid hormones help regulate metabolism and how efficiently your body burns food for energy. If your thyroid is under-functioning and your body is not producing enough thyroid hormone, your metabolism slows down, leading to weight gain. Other symptoms include fatigue, constipation, depression, cold intolerance, dry skin, hair loss and heavy and prolonged irregular menstrual bleeding. Another major issue and a common cause of persistent hypothyroid symptoms is the inability of your body to effectively convert T4, your inactive thyroid hormone, to T3, your active thyroid hormone. Some of the factors that can cause an inability to convert T4 to T3 include nutrient deficiencies especially iodine, selenium or zinc, gluten intolerance, medications, heavy metal toxicity and stress.


  1. Estrogen imbalance

 Excess estrogen can also make it hard for you to lose weight. Amongst women, estrogen exposure is known to cause weight gain, primarily through its influence on thyroid inhibition. Some suggest this is a woman’s mechanism by which she may accrue adequate fat reserves to be able to sustain a pregnancy. Xenoestrogenscan also influence weight gain and the inability to lose weight. Xenoestrogens are endocrine disruptors which are a category of chemicals that alter the normal function of hormones. When xenoestrogens enter the body, they increase the total amount of estrogen. They are not biodegradable and are thus stored in our fat cells. A build-up of xenoestrogens have been indicated in many conditions including breast, prostate and testicular cancer, obesity, infertility, endometriosis, early onset puberty, miscarriages and diabetes. The most common sources of exposure include animal products, parabens, plastics and BPAs.

Low estrogen states, such as in menopause, can also lead to a stubborn type of weight gain. One form of estrogen called estradiol which helps to regulate metabolism and body weight decreases at menopause. Lower levels may thus lead to weight gain. Lack of estrogen may also cause the body to use starches and blood sugar less effectively, leading to increased fat storage and making it harder to lose weight. 


  1. Lack of quality sleep

 Sleep affects two important appetite hormones in your body- leptin and ghrelin. Leptin is a hormone that decreases appetite so when leptin levels are high, the fuller you feel. Ghrelin, on the other hand, is known as the “hunger hormone” because it is responsible for the feeling of hunger. Research has found that lack of sleep increases levels of ghrelin and reduces leptin, making it harder for your body to know when to stop eating and increases the retention of fat. Reduced sleep has also been shown to have an impact on food selection and the way your brain perceives food, making you more likely to reach for carbohydrate-rich foods and sugar-filled snacks. Lack of sleep also influences metabolism, particularly glucose metabolism and can impair your body’s response to insulin, leading to insulin resistance. An excess of glucose (both from increased intake and a reduced ability to uptake into the tissues) could be converted to fatty acids and stored as fat.


  1. Prescription medications

Certain prescription medications can also be contributor to stubborn weight loss. Some of these include:

  • Drugs for diabetes, such as insulin, thiazolidinediones, and sulfonylureas
  • Antipsychotic drugs such as haloperidol, clozapine, and lithium
  • Antidepressant drugs like amitriptyline, paroxetine, and sertraline
  • Drugs for epilepsy like valproate and carbamazepine
  • Steroid hormone drugs like prednisone or birth control pills
  • Blood pressure-reducing drugs like beta-blockers




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  3. Rose E. Frisch, Body fat, menarche, fitness and fertility, Human Reproduction, Volume 2, Issue 6, August 1987, Pages 521–533, https://doi.org/10.1093/oxfordjournals.humrep.a136582
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