Just because you’re gobbling down avocados and waking up at the crack of dawn to hit the gym, doesn’t mean you’ve got that washboard stomachyou’ve been pining after.

That’s because the science of losing and gaining weight is not exact. While most people claim to understand what it takes to lose weight (but are just too lazy to do it), those who actually try to implement healthier habits may not be having much better luck in the svelte department. Trading in vegetable oil for olive, and replacing pasta with quinoa might push your body into a healthier state, but when it comes to melting fat the major saboteurs may have been flying under the radar this whole time. Here are ten.

1. Staying Up

Nothing helps you forget about your long day in the office better than catching up on the latest episode of the Walking Dead. However, flipping through the channels late into the night can inhibit your body’s ability to shut down and get some good quality sleep. “Cutting into sleep to get other tasks accomplished can contribute to difficulty with weight management. Sleep is key not only for immune system health, but also for regulating hunger hormones. Research suggests that less than five hours of sleep nightly may affect two key hunger/appetite hormones: leptin and grehlin. With less than five hours, subjects were found to have less leptin (which signals to the body starvation) and more grehlin (which signals appetite and want to eat) than usual,” says Isabel Smith, MS, RD, CDN, registered dietitian and founder of Isabel Smith Nutrition. She suggests aiming for 7-9 hours of sleep each night. Sometimes that means skipping your 5AM workout so your body has proper time to reboot and recover. “Not only do you have more energy to take on the day after a good night’s sleep but your body also torches calories even when you’re not working out,” adds Latoya Julce, Trainer and 305 Fitness Instructor

2. Forgetting to Hydrate

Hydration is key for more than just preventing muscle cramps and that weekend hangover. “This is a big one when it comes to appetite and hunger regulation. Sometimes when we’re thirsty we actually sense hunger, leading to overconsumption of food. Also, water is involved in the process of fat-burning so this may also play a role in weight gain as well. Aim for 64-80 oz fluid daily,” says Smith. Keep a water bottle on your nightstand and also on your desk at work to help ensure you’re getting your daily requirements of H20.

3. Skipping Check-ups

When was the last time you saw your doc? If your answer is ‘I don’t remember’, there’s a good chance you’re not where you want to be in terms of fitness because sometimes you need more than hours logged at the gym to get there. “Calories in minus calories burned is the most basic formula to control weight. But there are so many other factors that can affect weight gain—genetic predisposition, thyroid or other chemical imbalances, stress, lack of sleep, and more. Having a trusted relationship with a doctor whom you see regularly can help you pinpoint what is causing your weight gain or preventing weight loss. It’s during those regular preventive appointments that you can talk through adjustments to diet, exercise, and emotional day-to-day factors and keep track of your progress,” says Dr. Keri Peterson, a New York City internist who works with ZocDoc.

4. Eating by the Label

Just because the label says it’s fat-free—or natural—doesn’t mean it’s healthy. Let’s be honest—what part of cheetos could possibly be natural?! Avoiding processed foods altogether when you’re trying to lose weight will help your efforts by leaps and bounds, so don’t let that “natural” label sway you into choosing otherwise. The majority of packaged foods contain added, unnecessary ingredients like sugar or artificial sweeteners, salt, and trans fat, none of which will help those abs pop. However, if you’re not ready to depart with your love handles, by all means keep reaching for those organic tortilla chips and all natural queso.

5. Worrying About Work

Or anything for that matter. At the root of weight gain you’ll often find stress to blame. Not only does mulling over your week’s to-do list trigger emotional eating which can lead to weight gain, but as a result your body produces higher levels of the hormone cortisol, which causes your body to grip tighter onto it’s fat stores. Research from the University of Rochester Medical Center found that chronic job stress in addition to physical inactivity were strongly associated with being overweight, and a healthy diet was not enough to reverse the effects. The research pointed at exercise as one of the best ways to manage stress, and as a result—your weight.

6. Being Too Sweet

Drinking your coffee black is no easy feat, especially when you’ve tasted the shear delight that is coffee with cream and sugar (or vanilla-caramel-pumpkin flavored). However, those few teaspoons of sugar you stir into your cup of joe add up throughout the day and will later appear in the form of fat on your body. Not to mention, too much of the sweet stuff can send you on a high and bring your energy crashing down later causing you to feel lethargic and increase frequency of junk food cravings. If you absolutely need a little something to take the bitter edge off, Julce recommends using organic honey instead of white or artificial sugars.

7. Overeating Healthy Foods

Tossing the chips and pretzels to the curb for healthier swaps like nuts will certainly fuel your body better, but it may also hinder your weight loss efforts. Nuts are rich in healthy monounsaturated fats which support heart health and encourage greater feelings of satiety, however, the caveat is that they’re incredibly calorie dense. What it comes down to: filling up too much on almonds or walnuts will ultimately fill your stomach out. “Overeating otherwise healthy items like nuts and avocado can contribute to weight gain. Just because they’re good for you doesn’t mean they’re calorie free. For example one avocado has about 300 calories and 16-18 almonds have about 180 calories—both add up quickly. Aim to know portion sizes for calorie-dense yet healthy foods—it matters!” says Smith.

8. Grazing

Eating every few hours is important to keep your metabolism lit, but munching too much will only have you sucking it in to button your jeans later. While other factors come into play, total number of calories consumed affects your weight in a big way. Whether you’re eating from a bag of grapes or a bag of chips, it’s tough to track your total intake if you’re constantly eating throughout the day. Quit the constant snacking and instead have five small meals throughout the day to control hunger, prevent overeating, and better manage weight.

9. Skipping Meals

Passing on breakfast, lunch, or dinner will cost you more than just hunger pains. Forgoing lunch, for instance, can cause you to overeat later in the day and can also negatively effect your metabolism. “Just because you don’t eat all day doesn’t mean you’ll lose weight, and in fact I find that this is a major trend that men in particular take part in. They’re too busy and otherwise occupied during the day to focus on eating so they wait (for the most part) to eat later on in the day. In short, this can actually lead to weight gain. On top of this, people tend to eat much more in the evening if they haven’t eaten all day. Aim for three meals at the very least and better yet three meals and at least one snack,” says Smith.

10. Downing Diet Foods

They may lead you to believe otherwise, but low-fat and low-cal foods won’t necessarily help your diet in the long run. Many contain artificial ingredients and are lacking in whole foods and nutrients, which your body needs to function properly and also to maintain a healthy weight. “Eating lots of diet foods and diet soda may throw off your body’s sense of satiety, which may lead you to eat more. In addition, studies are showing that artificial sweeteners can throw off balance of gut bacteria, which can affect weight management and blood sugar control amongst other things,” says Smith. Instead, opt for fresh, whole foods as often as possible.