You’re doing everything right. Eating better, moving more, cutting out the junk — and the scale hasn’t budged. Not even a little. If that sounds familiar, I want you to know something important: you are not crazy, you are not lazy, and you are definitely not alone.

In my eight-plus years of working with women on their health and weight, I’ve seen this pattern over and over. Most of the time, making the right changes to nutrition and lifestyle makes a real difference. But sometimes? It doesn’t. And when that happens, there’s almost always a deeper, systemic reason — a root cause that nobody has thought to look at yet.

One of the most overlooked culprits? Leptin resistance. The symptoms of leptin resistance mimic plain old frustration — extreme cravings, a metabolism that won’t budge, weight that keeps creeping up no matter what you do. But there’s actually a hormonal reason behind all of it, and once you understand it, you can start doing something about it.

Today I’m breaking down the most common hidden causes of weight loss resistance — and then we’re going deep on leptin resistance: what it is, how to recognize the symptoms, and exactly what to do about it.

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First: What Is Weight Loss Resistance, Really?

Your body is brilliant. It knows exactly what to do with every carb, fat, protein, vitamin, and mineral you give it. It digests, absorbs, uses, and eliminates with incredible precision — when it’s in balance.

The problem is that at some point — often around age 35 or so — certain systems can fall out of balance. And once they do, the body holds on to weight no matter what healthy changes you make. The root causes of that imbalance are what need to be addressed.

So let’s talk about some of those causes — including a few sneaky ones you might not expect.

The Common (and Not-So-Obvious) Causes of Weight Loss Resistance

Food Sensitivities

Gluten, dairy, soy, corn, eggs — sensitivities to these foods can quietly trigger inflammation throughout the body. And chronic inflammation? It makes losing weight incredibly difficult. If you have a hunch that something you’re eating isn’t working for you, trust that instinct. Try eliminating it for three to four weeks and see how you feel. You know your body better than anyone.

“Health” Foods That Aren’t Actually Healthy

Granola, protein bars, flavored yogurt, smoothies from the drive-through — so many of these are junk food in disguise. They’re either loaded with sugar or packed with artificial sweeteners, which are just as problematic. Artificial sweeteners trick your taste buds and your brain into craving more sweets, and they’re toxic to the body. When your body can’t eliminate a toxin quickly, it stores it in your fat cells. And if your brain doesn’t feel safe releasing those toxins? It won’t let go of the weight.

Poor Gut Health

When your gut microbiome is out of balance — more bad bacteria than good — it sets off a cascade of problems. The bad bacteria produce endotoxins that drive chronic inflammation, cravings for sugar and junk food, fatigue, and yes, weight gain. Supporting your gut with probiotic-rich foods like sauerkraut, kimchi, unsweetened kefir, and kombucha, along with prebiotic foods that feed the good bacteria, is a powerful first step.

Hormonal Imbalances

Think of your hormones as a symphony. If one instrument is off-key, the whole orchestra suffers. Your sex hormones, thyroid hormones, stress hormones, and hunger hormones all work together. When one group falls out of balance, it affects all of them — and your metabolism, appetite, body composition, and ability to handle stress go with it.

The best starting point for hormone balance is always blood sugar balance: protein at every meal, no naked carbs (that means always pairing them with fat or protein), and ditching the refined white stuff.

Chronic Stress

We can’t always control what life throws at us, but we can control how we respond. Elevated cortisol — your primary stress hormone — makes it nearly impossible to lose weight, especially around the belly. Deep breathing, walks in nature, journaling, prayer, movement, time with people you love — find what works for you and be consistent about it.

Poor Sleep

Sleep and stress are deeply connected, and both drive cortisol — which drives belly fat. When you’re sleep-deprived, you also crave more caffeine (hello, more cortisol) and crash mid-day into sugar cravings (hello, blood sugar chaos). Research shows that people who sleep only five hours a night are 50% more likely to become overweight than those sleeping eight. That statistic still gets me every time I share it. Aim for seven to eight hours — it’s not a luxury, it’s medicine.

Thyroid Disorders

If someone comes to me having done everything right and still can’t lose weight, thyroid is one of the first things I ask about. Even if your levels are technically in the “normal” range, they may be low for you — and a sluggish thyroid means a sluggish metabolism. If you haven’t had thyroid labs done recently, that’s where I’d start.

Medications

Certain steroids, some birth control pills, certain antidepressants and anti-anxiety medications can make weight loss harder for some people. It’s not everyone — you are bio-individual — but it’s worth considering if everything else checks out.

What Is Leptin Resistance — and What Are the Symptoms?

Leptin is one of your two main hunger hormones — the other being ghrelin. Here’s the basic breakdown:

• Leptin is the “I’m getting full” signal. As you eat, your fat cells release leptin, which travels to your brain and says, “Okay, we’re good, slow down.”
• Ghrelin is the “feed me” signal. When you’re hungry, your stomach releases ghrelin to get your brain’s attention.

Leptin also works directly with your thyroid hormones to regulate your metabolism. When leptin is released, your brain is supposed to respond by boosting metabolism or dialing down appetite — your body’s natural self-regulating system for weight.

But here’s where it goes sideways.

What Is Leptin Resistance?

Leptin resistance is when the normal communication between your fat cells and your brain breaks down — and it leads to persistent weight gain and an inability to lose weight no matter what you do.

Here’s what happens: You don’t get more fat cells after adolescence. What changes is their size. When you gain weight, fat cells expand. When you lose it, they shrink. But when you’re dealing with chronic inflammation, a poor diet, too much stress, too little sleep, or hormonal and gut imbalances, your fat cells keep growing — and they keep pumping out more and more leptin.

Over time, your brain gets overwhelmed by all that leptin. Just like insulin resistance develops when the body is flooded with too much insulin, your brain starts tuning out the leptin signal altogether. It goes numb to it.

And then it gets even more frustrating: your brain, now blocked from receiving leptin’s signal, starts to think you’re leptin deficient. So it does what any good brain would do — it increases your appetite and slows your metabolism to compensate.

Your body is flooded with leptin. Your brain thinks you’re starving. Your metabolism slows. Your cravings go through the roof. And nothing you do seems to move the needle on the scale.

That’s leptin resistance.

Leptin Resistance Symptoms to Watch For

• You can’t lose weight even when restricting calories and exercising consistently
• Your metabolism feels slow or abnormal given your lifestyle and eating habits
• You continue to gain weight despite doing all the “right” things
• You have other hormonal imbalances — thyroid issues, estrogen dominance, low testosterone, high cortisol, or insulin resistance
• You have extreme cravings even after cleaning up your diet significantly

How to Test for Leptin Resistance

Ask your doctor to order a fasting leptin test (ideally after a 12-hour fast). Here’s what the numbers generally mean:

• 14–20 mcg/mL: Minor leptin resistance
• 40 mcg/mL or higher: More significant leptin resistance

It’s also worth checking your thyroid hormones, cortisol, and sex hormones at the same time to get the full picture of what’s going on hormonally.

What You Can Do About Leptin Resistance

The good news? Leptin resistance can be improved. It takes consistency and it takes time — but it is possible. Here’s what I recommend:

Build Muscle with Strength Training

Aim for at least two to three strength training sessions per week — three is ideal. Building muscle mass improves leptin sensitivity and boosts your metabolism.

Consider Intermittent Fasting — With a Caveat

A 12- to 16-hour fasting window can help sensitize your cells to leptin and bring levels down over time. That said, if you suspect adrenal fatigue — you’re exhausted, wired and tired at night, dragging through the day, waking up depleted — intermittent fasting might not be where you start. Listen to your body on this one.

Ditch the Processed Foods

Processed foods disrupt gut health and drive chronic inflammation — both of which fuel leptin resistance. This is non-negotiable.

Lower Your Triglycerides

Elevated triglycerides block leptin from crossing the blood-brain barrier — meaning the signal literally can’t get through. The most effective way to lower triglycerides? Cut back on simple carbs and refined sugars. This goes hand-in-hand with ditching processed food.

Supplements Worth Looking At

A few supplements have solid research behind them for supporting leptin sensitivity:

• Glycosaminoglycans (GAGs) — including hyaluronic acid, chondroitin sulfate, and glucosamine sulfate. These compounds help cells function properly, reduce chronic inflammation, and have been shown in both human and animal studies to help lower leptin levels.
• L-Glutamine — great for gut repair and intestinal barrier health, and has also been shown to improve fat mass, insulin levels, and leptin levels. I prefer powdered L-glutamine over capsules — it acts faster, absorbs better, and taken in the morning, it can help reduce sugar cravings throughout the day.
• Berberine — a powerhouse for metabolic support. (Check out Episode 66 for the full breakdown on berberine — it’s one of my favorites.)
• Fish oil / Omega-3s — a reliable inflammation fighter. Just make sure yours is third-party tested and free of contaminants and heavy metals.
• Alpha lipoic acid (ALA) and green tea extract — both show promise in supporting leptin sensitivity.

One More Thing Before You Go

If you’re frustrated about your weight, I want to gently point out something: stress about weight gain makes it worse. Elevated cortisol from that frustration actively works against you. So be kind to yourself as you work through this.

Reversing leptin resistance isn’t an overnight fix — it typically takes several weeks to a few months to start seeing real changes. But here’s the thing: don’t fixate on the scale. That number is the last thing to move. What changes first is how your clothes fit, how strong you feel, how your energy shifts. Pay attention to those wins. They’re the real markers of progress.

If you’re combining a whole-food diet, consistent strength training, proper sleep, stress management, and targeted supplements — you are doing the work. Give yourself credit for that.

You’ve got this. Stay pretty well. ✨