Your diet is clean. You have a pantry full of supplements and haven’t missed a training session in six months. Yet you still don’t have the body you want.

This is a common dilemma. There’s a tendency to blame genetics or look at magazine covers and assume those folks are taking something not readily (or legally) available. But there actually are four reasonable explanations for why you are not progressing the way you’d like to be.

You’re in a bad relationship

Bad relationships lead to stress, and there are few things worse for your body composition than stress.

This applies to much more than romantic relationships. Overbearing parents and in-laws, an abusive boss, and needy co-workers, friends, and acquaintances, can stress out your system and cause you to hold onto fat, especially in the abdominal region.

Cutting bad relationships can be difficult – sometimes impossible. You’re pretty much stuck with the parents and in-laws, and unless you switch jobs, the boss and co-workers aren’t leaving either. But make an effort to cut as many toxic people out of your life as possible and you will be happier and healthier for it.

You’re intolerant

This one is a real kick in the pants. You eat everything you’re supposed to – eggs, fish, lean meat, gluten-free whole grains, nuts, fruits, vegetables – and yet, you can’t shake those last five pounds of fat.

You could have a more stealth version of a food allergy: a food intolerance. Such an intolerance causes inflammation in the body. Not a full-blown, swollen-faced allergic reaction, but low-level inflammation that keeps your system from running smoothly.

If your system isn’t running correctly, dropping fat is the least of your problems. Eggs, nuts, soy, wheat and dairy are the “Big Five” when it comes to food intolerances but you can be intolerant to anything from garlic to parsley to pineapple to eggplant. And, chances are, the more you eat something (and people tend to eat the same things when on a fat loss plan) the more likely your body will become intolerant to it. I told you it was a kick in the pants.

Things such as food intolerance tests (performed through blood work) and elimination diets can identify the culprits. Eliminating these foods might be all you need to jump start your training program.

You’re polluted

Remember Britney Spears? She wasn’t exactly a rocket scientist, but she might have been on to something when she sang, “You’re toxic!”

Environmental toxins -pollution, cigarette smoke, cosmetics, metal tooth fillings, prescription drugs, and mercury in fish – are stored in fat cells, and have the potential to wreak havoc on your body.

Since your body is smart, and prioritizes survival over ripped abs, it refuses to use these fat cells for fuel. Doing so would release these toxins into general circulation. Essentially, you are holding onto these fat cells so the toxins don’t make you ill.

So how do we get rid of these unwanted guests, become less toxic, and drop that last chunk of stubborn body fat? You could take measures ranging from infrared saunas, detoxifying foot baths, chelation therapy, all the way to liver and GI tract detoxifying diets. These methods can help you remove metals and toxins from your system.

Such measures can be fairly dramatic depending on the source of the toxicity. Consult a specialist before taking on any type of intervention, to determine what, if anything, is appropriate.

You’re not working hard enough

Just because you’ve been working out consistently doesn’t mean you are getting the most out of your training. If showing up is half the battle, the other 50 percent is the effort you bring to the gym.

Most people do not realize what their bodies are capable of enduring. Are you leisurely working on a cardio machine while reading a magazine or talking on the phone? Do you continue to do the same workouts long after your body has adapted to them?

If so, take a look at the folks in your gym who appear to be getting results. Chances are, they’re pushing themselves, working at a furious pace, and continually undertaking new regimes.

There’s a reason those people have better body compositions than you do. It’s not by accident or genetics; they’re busting their asses – and you can too.

You’ve already done the hard part by dedicating the time and showing up. Now just commit to working harder.