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17 Reasons You Can't Lose Weight, According to Nutritionists

If you've been working hard to drop those unwanted pounds but the scale still isn't budging, you could be making these mistakes.

So you've been diligently counting calories, hitting the gym a few days a week, and drinking your 64 ounces of a water a day. So why won't the scale budge? You could be sabotaging yourself without even realizing it.

Even some "healthy" habits that you've been incorporating into your weight-loss routine could actually make the scale stall—or worse, go up. So what gives? We tapped these nutrition experts on some of the biggest mistakes they see their clients making on their weight-loss journeys. With just a few simple changes, you may finally see the scale go down. And if you need more inspiration, check out our list of the 100 Best Weight Loss Tips Ever.


You Skip Breakfast

Woman eating cereal

"Skipping breakfast and having two large meals instead. Unless a person is intentionally using an intermittent fasting technique, eating in this way can lead to eating very large meals, which doesn't favorably affect blood sugar and weight. It also leads to wonky leptin, which is a hormone secreted by fat tissue that plays a role in one's ability to lose weight. We want our leptin to be efficient, so having a protein-based breakfast within 30 minutes of waking up can lead to a better hormonal profile for weight loss."

— Nicole Anziani, CDE, Fit4D


You're Ignoring Overall Health

Chicken avocado salad

"[A] weight loss mistake people make is focusing too much on calories and not enough on health. I counsel clients to help them feel good and healthy. I want them to have high energy levels, feel good in their clothes and ward off any diseases. Usually, this means that they will be eating a healthier than normal diet with plenty of produce, lean proteins and healthy fats, all of which have been tied to weight loss. I'm also a big advocate of the 80/20 rule—that is, eating as much healthy food as you can 80 percent of the time and indulging in your favorite treats 20 percent of the time. I think if someone has healthy behaviors, the numbers on the scale will reflect that."

— Natalie Rizzo, MS, RD


You Don't Believe You Can

Woman cravings

"There are several reasons why people can't lose weight and it starts with them actually believing that they can't. I've never heard someone say 'I can't lose weight,' and magically start seeing pounds drop. The first step to losing weight is to reset your mindset and welcome weight loss so it can actually happen… People don't realize it but when they say, 'I can't lose weight,' it impacts all of their food choices and they begin to self-sabotage. For instance, 'I might as well finish my kids chicken nuggets or this container of ice cream because I can't lose weight anyway.' Our body achieves what our mind believes. Therefore, when you start repeating and believing 'my body loves losing weight and I am in weight loss mode,' all of your food choices and behaviors will start to set you up for success so you can start meeting your weight loss goals."

— Ilana Muhlstein, RD, nutritionist for Explore Cuisine


You're Not Getting Enough Sleep

Tired man

"Not getting enough sleep can make it difficult to lose weight. It's recommended to get 7-9 hours of sleep per night. Too little sleep can make us feel foggy headed and tired the next day. To help combat the fatigue, our body craves food, usually in the form of sugar. This makes it difficult to eat mindfully."

Lauren Manganiello MS, RD, owner of Lauren Manganiello Nutrition & Fitness


You Don't Pay Attention to Portions


"It's easy to go overboard on portioning without even realizing it. Grabbing handfuls here and there can quickly add up. When you find yourself snacking out of a bag, you easily lose track of how much you've consumed. Our plates and bowls are also much bigger nowadays meaning we tend to eat more simply because we like to see a filled plate rather than a plate with appropriate portions and empty spaces."

— Gina Hassick, MA, RD, LDN, owner of Eat Well with Gina


You Graze All Day


"What can happen is that patients end up eating lots of extra calories through tiny tastes and snacks and never give their bodies a chance to tap into their fat stores. They are constantly spiking their insulin and blood sugar and are telling their body to store, versus use, their fuel."

— Nicole Anziani, CDE, Fit4D


You're Too Restrictive


"I often find my patients not being able to lose weight when they believe that restricting will lead to a rapid weight loss. Patients that purposely restrict will inevitably overeat at some future point. It is hard to maintain a calorie-restricted diet without sabotaging these efforts. I believe that a healthy and sustained weight loss can occur when you are consuming a balanced diet with one or two 'treats' during your week. The idea is not to restrict, but to avoid most unhealthy foods on most days."

— Leah Kaufman, MS, RD, CDE, CDN


You're Not Being Consistent


"I would say the behavior I see the most is not being consistent and letting things slide because of one bad meal, snack, or event. For example, someone will put in three good days then something comes up where they don't feel like they were 'perfect,' and they say, 'oh well, I messed that up so what's the point' and they continue to eat poorly until Monday or so. I always tell my clients, consistency is what gets you the results. So even if you have a bad moment, get right back on track the next time you eat. The one bad meal is never the reason why you gain weight, it is what happens over and over that does."

— Amy Shapiro MS, RD, CDN, Real Nutrition NYC


You Overeat After Workouts

Man eating

"If you're allowing yourself to end each workout with a high-calorie sports drink or a huge meal, you're almost instantly eating away the calories you just burned. Sugary sports drinks may be the biggest culprit in this regard. Your best bet is to stick to water to rehydrate after exercise. Keep post-workout snacks small: a stick of low-fat cheese, reduced-fat chocolate milk, or half of a protein bar that has both protein and carbohydrates."

— Ashvini Mashru, MA, RD, LDN


You Eat Too Many Carbs at Breakfast

couple eating donuts

"A bowl of cereal with milk is very low protein and likely low fiber unless a very 'whole' grain is chosen. That can set a person up for a blood sugar crash which can lead to excess hunger and poorer choices throughout the day. Aiming for a higher fiber and lean protein choice can hold you longer and help support you starting the day on the right foot."

— Nicole Anziani, CDE, Fit4D


You Forget How Much You Actually Ate


"I find that people sometimes underestimate how much they eat. A dinner entree at a restaurant can easily top 1,500 calories and sometimes we continue to eat just because it's there. Sitting in front of screens and binge watching your favorite shows might lead to mindless binging on treats. Before you know it, an entire bag or bowl of snacks is gone. With both of these, there's an easy reset. Pause before a meal or put less in the bowl before starting the show—this built-in speed bump might help you be more mindful and help you recognize hunger and fullness cues a little better."

— Marisa Moore, RDN, Marisa Moore Nutrition


You're Focusing Too Much on Exercise

Weight training

"Many people think they can exercise enough to burn off extra calories—you can't outrun a bad diet. You can work out seven days a week, but if you're eating too much, or [eating] bad-for-you foods, you won't get the results you are after."

— Amy Shapiro MS, RD, CDN, Real Nutrition NYC


Or You're Only Doing Cardio


"Sometimes, when people are focused on losing weight, they only want to burn a lot of calories through doing cardio. While burning calories is certainly important, sometimes they engage in a volume of cardio that is difficult to sustain long-term. Metabolically, their bodies may hold on to fat stores if they are exercising heavily and not eating enough calories to sustain it. It also seems that they shy away from lifting weights and building muscle because of the fear of 'bulking up.'

"In my opinion, there is nothing better you can do, fitness-wise, for your overall health and long-term weight success than build muscle. A combination of cardiovascular training and weight training is the secret sauce for the success I've seen in clients. It may not result in as many total pounds lost, but that number doesn't matter if your health and body composition have improved. In addition, people that appropriately eat to fuel their fitness are also the most successful. Exercising like crazy and eating very little is a pretty surefire way to sabotage long-term success."

— Chelsea Elkin, MS, RD, CDN


You Don't Factor in Liquid Calories

Woman drinking champagne

"I think the biggest weight loss mistake I see people make is not thinking about liquid calories. So many people forget that things like a nightly glass of wine or an occasional sports drink have added calories that don't help satiate you. When you're trying to lose weight, those extra calories stunt the process. Instead, opt for things like fruit-and-herb-infused water, or cut your wine with seltzer to make a spritzer."

— Natalie Rizzo, MS, RD


You're Not Meal Prepping

Meal prep

"If you don't plan or prep, you are likely going to have to rely on willpower to make your best decision when you are tired, busy, and otherwise distracted. Life can get the better of us, so planning which day you will grocery shop, food prep, and cook, will help assure that you have the tools you need on-hand to make better food decisions when it counts."

— Nicole Anziani, CDE, Fit4D


You're Not Eating Enough Calories

hungry woman

"Many dieters make the mistake of thinking that if they cut more calories, they'll lose weight faster. Although, I warn that the opposite is almost always true. Trying to maintain a diet that is very low in calories leads to sabotage in the form of binging and, ultimately, giving up. Plus, cutting too many calories stalls your metabolism possibly for the long-term. In general, women shouldn't eat less than 1,200 calories and men less than 1,500 calories a day, and even these levels are pretty tight."

— Ashvini Mashru, MA, RD, LDN


You Believe in the Health Halo

Granola jar milk

"Some [of my] patients get tricked by food marketing and think that things like granola, or energy bars, or bottled green tea that is sweetened are healthy when really, they just add empty calories and a blood sugar spike."

— Nicole Anziani, CDE, Fit4D

"Misreading nutrition labels or assuming certain foods are good for us [is a problem]. So yogurt parfaits, smoothies, granola, energy bars. Don't assume; look at the label and then reassess."

— Amy Shapiro MS, RD, CDN, Real Nutrition NYC

To make sure you're not falling for any of these so-called "healthy" foods that are really junk food in disguise, make sure you avoid the 32 Health Halo Foods to Stop Eating Immediately.