Why Can’t I Lose Weight? Surprising Reasons Behind the Struggle

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Why Can't I Lose Weight No Matter What I Do
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If you’ve been eating right and exercising but have noticed a stall in your weight loss, you’re not alone. Unfortunately, some people find that a healthy diet and daily exercise routine are not enough to achieve their goal weight. 

The truth: Diet and exercise are just two small pieces of the puzzle. A plethora of underlying factors could be contributing to stubborn weight that just won’t budge.

You may have read that weight is simply a matter of calories in, calories out. But, this old adage is flawed. We now know that weight loss plateaus are more complex than restricting calories and exercising more. 

There are a variety of underlying causes, both biological and habitual, that could be preventing you from reaching your weight loss goals. Let’s take a look at some of the most common causes behind why you can’t lose weight, and how you can overcome them.


We all know someone who can eat ice cream, cake, and whatever else they want and still not gain a pound. On the other hand, there are others who seem to gain weight just by looking at a dessert. It can be excruciating to watch friends and family members enjoy their food while you struggle to lose weight no matter how small your portions are or how diligent you are with your diet.

Many people, even some who work in the health and wellness space, will tell you that your weight is determined by how many calories you consume, store, and burn. Full stop. But, that’s an oversimplification and doesn’t include how things like the type of bacteria in your gut microbiome as well as your genetics and environment influence how much you weigh. 

Researchers have identified over 400 different genes linked to being overweight or obese. These genes can affect metabolism, appetite, satisfaction, fat distribution, and food cravings. Some genes also predispose you to eat when you’re stressed. While your genes can create a disposition to certain conditions, such as obesity, just because you have them doesn’t necessarily mean that they’ll be expressed. This means you are not destined to develop certain health issues just because you have a genetic predisposition! 

Although your genes play a key role in your health, your environment, lifestyle habits, and behaviors also contribute to your health outcomes. This is called epigenetics, the study of how our environment and behaviors influence the way our genes are expressed. Research suggests that obesity is driven by both environmental and biological factors. 

Depending on your genes, they may account for anywhere between 40–70% of your predisposition to be overweight. One review of gene discovery studies on obesity reveals that our central nervous systems and brain cells control how much pleasure we get from food. This appears to be a major driver of body weight. 

We all get cravings and love to eat comfort foods from time to time, but if you feel out of control of your impulses when it comes to certain foods or drinks, this could be a sign that something’s off. You could be genetically predisposed to get way more exhilarated by a piece of cheesecake than your partner or friend — and be driven to eat more of it once you have a taste. This effect can snowball. 

What can you do if you suspect you get heightened pleasure out of sugary-fatty or salty-fatty or sugary-salty-fatty foods (aka highly palatable foods) and you just can’t stop until the thing is gone? You can’t change the genes you were born with, so work with the things you can control, like your environment:

  • If you can’t control your urges to eat the whole thing, take a break from it for a while. Don’t keep it in your house. Allow yourself to have it on special occasions when you’re at a restaurant or ice cream shop or friend’s house and your portion is limited. Just say no if your friend offers you some to take home with you.

  • Avoid binge drinking at parties or happy hours where you have unlimited access to deep fried things, chips and dips, or pastry-wrapped hors d'oeuvres. The extra alcohol will loosen your inhibitions and dare you to eat more than you need.

  • Steer clear of all-you-can-eat buffets. Stick to reasonable portions of healthy foods (think vegetables, fruits, lean proteins, heart-healthy fats like avocado and nuts, unrefined whole grains, and small amounts of dairy if you can tolerate it) the majority of the time.

  • When in doubt, pick whole foods over processed and basic preparations over sexed-up and saucy. It’s true that it’s hard to overeat apples, but not cookies. Try it sometime if you don’t believe — bet you’ll give up trying to eat 15 apples at one time because you just won’t want more than two or three. Same concept with something like green beans. It’s unlikely you’ll eat yourself sick from steamed green beans, but you have a decent shot at it if those beans are deep fried and served with ranch.

By understanding how much control you have over how your genes are expressed, you can empower yourself to use lifestyle cues to change your environment. 


Your hormones are important chemical messengers that facilitate virtually every bodily process including metabolism, fat breakdown and storage, and the number of calories you burn each day. 

Your hormones send out signals of hunger, fullness, and satiety (feeling satisfied), which means they heavily influence your weight. If your hormones are unstable, those fluctuations could lead to unintentional weight gain and concentrated fat accumulation.

For example, your thyroid produces hormones that regulate your metabolism. Hypothyroidism is a common condition caused by an underactive thyroid that does not produce sufficient amounts of thyroid hormone. This condition leads to decreased energy expenditure (you burn fewer calories), which often leads to unintentional weight gain.

Insulin, a hormone produced in your pancreas, is the primary storage hormone in your body, and helps regulate your blood sugar levels. When you eat food, your body begins to break it down into glucose, your primary source of energy. When the glucose reaches your bloodstream, your pancreas begins producing insulin to help deliver the glucose to your muscle, fat, and liver cells to be used later when your body needs energy. Once the glucose is safely stored away, your insulin production decreases.

If your insulin levels are consistently elevated over a long period of time, this could lead to insulin resistance, a condition that leaves you with chronically high blood sugar since your cells can’t take up glucose efficiently. Although the CDC acknowledges that they have not yet identified a clear-cut cause of insulin resistance, ongoing research offers some insight as to what could be behind this complex condition. 

Once you’ve developed insulin resistance, your insulin production increases to maintain your blood sugar levels. Insulin resistance is associated with weight gain, cardiovascular disease, type 2 diabetes, and obesity-related cancers. If you have a family history of type 2 diabetes, live a sedentary lifestyle, or have excess belly fat, you may be more predisposed to developing insulin resistance.

Certain hormones also affect how your body responds to weight loss strategies. One of these hormones is leptin, which plays a profound role in weight loss. As you lose body fat, your leptin levels decrease, which sends signals to your body that it’s starving, stimulating intense hunger cues and cravings. This could cause overconsumption of food and, as a result, unintended weight gain.

The great news is that you can optimize your leptin sensitivity to help you achieve your weight loss goals. Some ways to improve your leptin sensitivity include:

You can balance your hormone levels by eating plenty of fiber, heart-healthy fats and fatty fish, minimizing stress, exercising regularly, avoiding sugar, and getting a good night’s sleep each night.

Gut Health

Many of us grew up hearing the phrase, “you are what you eat!” The truth is you are what you can digest and absorb. 

New research is clarifying the role that our gut microbiota plays in weight loss. In a report by American Society for Microbiology, lead study author Christian Diener, Ph.D., research scientist for the Institute for Systems Biology in Seattle, WA, says, "Your gut microbiome can help or cause resistance to weight loss. This opens up the possibility to try to alter the gut microbiome to impact weight loss."

Your body contains trillions of bacteria, most of which are located in your gut (also known as your gastrointestinal system). In addition to immune system function and the manufacturing of certain vitamins, the bacteria in your intestines play a role in how your body digests food, and produces chemicals that signal to your brain that you’re hungry or satisfied.

A study conducted on obese and lean twins provided evidence that those with obesity had less diverse gut bacteria than their leaner twin. Several other studies showed that higher fiber intake is associated with a lower weight, which could be a result of the role that gut bacteria plays in digesting dietary fiber.

Another factor to take into consideration is the use of antibiotics. Research tells us that using antibiotics on babies, children, and adults severely alters their gut bacteria. The effects that antibiotics have on the microbiome could be long-lasting, with one study showing a continued change in gut bacteria an entire year after a round of antibiotics lasting just 10 days. 

If you’re prescribed antibiotics, your doctor will likely advise that you take a probiotic supplement or consume probiotic-rich foods such as sauerkraut or yogurt to help offset the effects of the antibiotics. This is not to say that you should avoid antibiotics altogether. Sometimes they are necessary, and the benefits of the treatment may outweigh the potential side effects. It’s important to have a discussion with your doctor to determine how you can best support your gut microbiome during the treatment.

Balancing the bacteria in your gut can optimize the way your body digests and absorbs the foods you eat, how fats are absorbed by your intestines, and how your body stores fat. You can accomplish this by:

  • eating fiber from fruits and vegetables, whole grains, beans, and legumes 

  • eating fermented foods like kimchi, sauerkraut, sourdough, and kombucha

  • adding probiotic-rich dairy foods like plain yogurt, kefir (try one with less added sugar), and aged cheeses (parmesan, cheddar, gouda)

  • getting more high-quality sleep 

  • managing stress 

  • staying hydrated

Poor-quality Diet

In the previous section, we talked about how gut health has a direct impact on the way your body absorbs, digests, and stores the nutrients you eat. A healthy gut relies on a nutrient-rich diet so it can maintain strong intestinal walls and optimal digestion. Unfortunately, many of us grew up eating a Standard American diet, even into adulthood, and may experience the effects of gut permeability, or leaky gut (where your gut lining has cracks or holes in it).

Our modern high-sugar, low-fiber diets drive gut inflammation, which can increase risk for health conditions including celiac disease, asthma, fibromyalgia, autoimmune diseases, and obesity. In addition to poor diet, other risk factors for leaky gut include pregnancy, extreme endurance exercise, and using NSAIDs (common non-steroidal anti-inflammatory drugs are ibuprofen or  aspirin). 

It’s important that you avoid self-diagnosing and treating yourself for leaky gut without a formal diagnosis. The only way to know for sure that you have a leaky gut is to get tested by a medical professional. The research on leaky gut is ongoing. Experts agree that there’s still much to learn about the condition but data is accumulating to support that changes in the gut barrier may contribute to the onset of various diseases.

The CDC reports that 20% of young people aged 2 to 19 years and 42% of adults in the United States have obesity, which may put them at higher risk for type 2 diabetes, heart disease, and certain types of cancer

Science-backed data suggests that a healthy diet includes: 

  • limiting alcohol, sugar, processed foods, and excess saturated fats 

  • eating whole, nutrient-rich foods like a variety of fruits and vegetables, lean proteins (including fatty fish and seafood) or plant-based protein sources, whole grains, healthy fats (avocados, olive oil, walnuts, chia seeds), and probiotic-rich dairy or non-dairy sources of probiotics

Medical Conditions

Balancing your hormones, optimizing your diet, and improving your gut health will help you make great strides on your weight loss journey, but certain medical conditions could also impede your progress.

Earlier we mentioned how insulin resistance and hypothyroidism could contribute to stubborn weight gain, but there are many health conditions that could affect your ability to lose weight. Polycystic ovary syndrome (PCOS), diabetes, adrenal fatigue, menopause, low testosterone, and congestive heart failure can play a role in your ability to maintain a healthy weight. If you’re struggling to lose weight despite your best efforts, talk to your doctor about your symptoms and begin taking steps to identify potential underlying causes of your weight issues.

Determining the underlying cause of your weight issues is the first step to achieving your weight loss goals. Get matched with an online personal trainer through Kickoff to develop and stick to a personalized weight loss plan. Your trainer will keep you motivated and on track throughout the process.