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21 Warning Signs You Need to Change Your Diet—Fast

If you fall into any of the categories below, then a red flag should go up that you might not be able to keep your weight down in the long run.

People think they need to deal with the negative side effects of their diet to reach their better-body goals—but that's far from the case.

If long-term success is what you're after (and it should be), then it's time to snap out of it and take a discerning look at your approach to weight loss.

If you've chosen to follow the wrong diet for your body type, it could end up making you sick and even cause weight gain.

Not sure if your diet is a winner? There are many warning signs your body is telling you that the diet you're following isn't the right choice—and it may even be making you sick. Vet yours against our list below to find out if yours may ultimately leave you with love handles and muffin tops—and then find out the 25 Easy Ways to Lose 5 Pounds, According to Experts!

You're constantly binge eating

Bored guy lying down on couch eating potato chips and drinking a beer

Constantly find yourself downing entire cartons of ice cream or sleeves of cookies? Despite what you may think, it's not because you have a lack of willpower. In fact, it's likely a sign you need to change up your diet. "Binging is your body's way of responding to not getting the nutrients that you need—it's a biochemical response and signal from your brain that you're not giving it what it needs," explains registered dietitian Cassie Bjork, RD, LD of Healthy Simple Life.

You're tired all the time

Tired young African man using laptop while sitting at the table on a sunny morning.Concept of people working hard home

If carrying your little one down a flight of stairs feels like a challenge, your diet may be to blame. "Being tired or constantly fatigued is your body's way of conserving energy when it's not getting enough of what it needs. It's a result of your metabolism slowing down—the opposite of what you want to happen for weight loss," says Bjork. registered dietitian Isabel Smith, MS, RD, CDN, owner of NYC-based Isabel Smith Nutrition and Lifestyle. concurs. "When you don't eat enough protein, for example, the body will start to break down stored proteins in the form of muscle and other tissues. This can shrink your muscle mass, making workouts and everyday physical activities more challenging." Other possible culprits: Processed and sugary fare. When eaten in excess, these foods can mess with your blood sugar levels and leave you feeling drained. To cut back on the white stuff and amp up your energy, check out our exclusive report, 30 Easy Ways to Stop Eating So Much Sugar.

You have digestive issues


Digestive discomfort, constipation, and diarrhea can all be signs that your fiber intake is out of whack. If you've been eating a lot of processed foods or recently cut back on carbs (but didn't up your intake of fibrous produce), you're likely not eating the recommended 28 grams of daily fiber. On the other hand, if you've recently started eating whole grains, beans and produce, you may have increased your intake too quickly, which can also cause discomfort. To counteract your belly issues, wean yourself onto higher fiber foods, starting with small portions. Another trick: Sip a large glass of water with every high-fiber meal. Fluids help to move fiber through the digestive tract, preventing bloat and discomfort. For more flat belly hacks, check out these 25 Best Foods for a Toned Body.

Your progress has hit a plateau

young brunette woman standing on a scale

At first you were losing weight faster than a contestant on "My Diet Is Better Than Yours" but lately, your progress has been stalled—and it might be because you're not getting enough carbs. "A low-carb diet can stall weight loss because if you suddenly eat fewer carbs, the liver tries to make up for it by producing sugar," says Bjork. "When blood sugar levels rise, the pancreas secretes insulin, your fat-storing hormone, so you store fat instead of shedding it." The good news is that carbohydrate cycling can counteract this. "One day each week, add in more carbohydrates than you normally would," says Bjork. Don't down an entire loaf of bread, though. An extra sweet potato or piece of fruit should do the trick!

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You get bad headaches

woman with closed eyes suffering from headache

While getting headaches from time to time is normal, having them every day after changing up your diet plan may be a sign you've taken things too far. "When you don't eat enough carbs or food in general, blood sugar levels can dip and cause headaches," says Smith. To keep the pounds coming off and head-pounding pain at bay, incorporate some carb-rich, produce like apples (one of the Best Fruits for Weight Loss), pears, and carrots into your daily diet.

You're down in the dumps

sad woman sitting on a couch

When it comes to the connection between omega-3s and depression, study results have been mixed. Though some research shows no mental health effects of consuming—or not consuming—the nutrient, other reports say that eating too few omega-3 fatty acids (which are found in foods like olive oil, wild salmon and walnuts) can make people more susceptible to the blues. If your change of mood came around the same time as your change of diet, a lack of fatty acids might be to blame. Thankfully, if you up your intake of the nutrient you should feel like your old self in no time!

Your memory is zapped

Girl with thinking expression trying to remember something at the cafe

Lost your keys—yet again?! Your crappy diet may be to blame. According to recent reports, what's bad for your heart is also bad for your brain and memory. In one Annals of Neurology study, women who ate the most saturated fats from things like butter and burgers performed worse on thinking and memory tests than women who ate the lowest amounts of these fats. To keep your memory sharp, cut back on those huge burgers from the McDonald's Menu and add more fruit, vegetables, whole grains beans, nuts, seeds and lean proteins and low-fat dairy to your diet. "These foods provide the vitamins, minerals, flavonoids and antioxidants that keep our brain cells at peak performance," says registered dietitian Christine Palumbo, MBA, RDN.

You're irritable and hangry

Annoyed woman cranky on laptop

No one knows the meaning of "hangry" quite like someone on a diet. When people first cut back on calories and carbs it can make them crabby—mostly because their blood sugar levels are low, explains Smith. To counteract your irritability, try adding more carbs to your plate. The nutrient is essential to the body's production of serotonin, a feel-good chemical that's produced in the brain. Noshing on some of these 23 Foods Happy People Eat can help, too.

You have major skin issues

Woman with problem skin

If you've recently started to break out or develop wrinkles, it may be a sign that your diet isn't healthy. "Skin issues are frequently a result of inflammation, which can occur if someone is following a diet that's low in fat and high in carbohydrates," says Bjork. "Once in the body, all carbohydrates turn to sugar, a nutrient that causes inflammation." Vitamin and mineral deficiencies and consuming too few fatty acids can also wreak havoc on your skin. To counteract your issues, consider changing your diet and be sure to add these 7 Foods That Make You Look Younger to your plate.

You plan your life around your diet

Large dinner party restaurant

There's a fine line between being committing to a weight loss plan and being obsessed with it. If you plan your entire life around your diet, it may be hard to stick to in the long run. Parties, dinner with friends, and eating at restaurants are a big part of life—and things you'll want to partake in without fear of weight gain. A smart, sustainable diet is one that will allow you live a fun, fulfilling life—all while losing weight and getting healthier. And once you've made the transition to an easer-to-follow plan, consider ordering one of these 25 Restaurant Meals Under 500 Calories next time you dine out.

Your cuts don't heal

woman touches her bruised knee

"Whether you've cut yourself while shaving or nicked your finger while chopping veggies, eating a healthful diet can optimize the amount of time needed to heal your wound," says Palumbo. Protein and vitamin C both play vital roles in wound healing, so it's important to consume sources of each nutrient daily. "Good sources of vitamin C include red bell pepper, papaya, green bell pepper, broccoli, strawberries, tomato juice, cantaloupe mango, cabbage and even potatoes," says Palumbo.

You cut out major food groups

Woman refusing to eat bread

On the other side of the equation, diets that forbid entire food groups like carbs or dairy aren't sustainable either. Unless there's a medical reason to scratch something from your diet—like lactose intolerance, for example—we advise against it. The reason: If cutting out a certain food helps you shed weight, you can sure it will cause the weight to pile back on as soon you start eating it again. To start losing weight today—a smarter way—check out these 10 Genius Tips to Lose 10 Pounds!

It makes you pull a 180

Plant based vegan salad bowl

If meat and eggs are cornerstones of your diet, turning to a vegetarian or vegan diet to lose weight will likely fail you in the long run. Typically eat on the run? Then a diet that requires extensive home cooking probably isn't the best fit. If your plan isn't compatible with your lifestyle, the odds are good you'll fall off the bandwagon and regain the weight. To lose weight without overhauling your lifestyle, check out these 25 Ways to Lose Weight in 5 Seconds.

You're dreaming of the drive-thru

fast food hamburger

If you constantly find yourself dreaming of the drive-thru and fantasizing about French fries it may be a sign that you're not giving your body the nutrients it needs, says Bjork. "Many diets cut fat since it's higher in calories than protein and carbs, but this tactic can backfire by increasing cravings. A simple way to keep cravings at bay is to add a couple of tablespoons of healthy fat like avocado, olive oil, nuts or seeds to all of your meal and snacks. These healthy fats will keep your blood sugar levels stable and ward off sugar cravings, which will ultimately aid weight loss!"

You eat everything in moderation

high protein almond snack in hand

Diets that allow you to eat everything in moderation may seem smart, but some experts say that they may backfire. "Though it can be scary to imagine completely cutting out the foods that you love, eating everything in moderation is actually near impossible—especially when it comes to foods with addictive properties, like sugar. More often than not you'll find yourself going back for more and more which can slow your weight loss results," explains Bjork. "That's why it's more beneficial to completely cut out the foods that increase your cravings and keep you wanting more." For example, if you know that chocolate is your #1 trigger food it's best to cut it out altogether rather than trying to stick to one small square.

It's really convenient

man microwaving frozen meal

There's no denying that prepackaged meals, shakes and bars make dieting and portion control a no-brainer, but let's face it, you're not going to stay on the program forever so gaining the weight back is practically inevitable. "After a while, people tire of the same menus, the same pre-packaged foods, bars, and shakes and want to eat what they enjoy. They want to go out to eat with their friends and invite their family over for meals. For most people, it is simply unrealistic to stay on these programs indefinitely." If sustainable weight loss is your goal, kick the shortcuts to the curb and slim down with the help of these 44 Ways to Lose 4 Inches of Body Fat instead.

Every day is a bad hair day

Woman brushing her hair with a wooden comb

"While the biggest predictor of lush, beautiful hair is heredity and age, diet plays a role, too," says Palumbo. "A poorly planned diet that's low in calories, protein, iron or fat can result in thinning, brittle or dull looking hair." The goods news is that it's totally possible to undo the damage. To boost your hair's luster, Palumbo suggests enjoying plant oils and oily fish like tuna and wild salmon. If thinning locks are your primary issue amp up your protein intake with the help of these 29 Best-Ever Proteins for Weight Loss.

You can't stop shivering

Young man suffering from cold at his home

Despite the fact that your thermostat reads 70°F, your teeth are chattering. Unless you have a fever, it's likely a sign that something with your diet is off. "Low-carb dieters are at risk of developing a low thyroid function, which can make it difficult to regular internal body temperature," says Bjork. Don't just ignore your cold fingers and throw on a sweater—head to the kitchen and make yourself a delicious bowl of oatmeal. After you've added more carbs back into your diet, the constant chill and chattering teeth should subside.

Your workouts are dragging

Tired woman at gym struggling to finish treadmill workout

"Carbs are the first line of use for energy for the body, so when muscle stores of carbohydrates are low, it can make some people feel lethargic and less able to sustain a high-intensity workout," says Smith. Dial up your carb count before your workout to ensure you have enough energy to blast away belly fat. And afterward, do the same. This will ensure you're replenishing lost energy stores so you can hit the gym again tomorrow.

You're always sick

woman feeling sick and seasonal flu symptoms

Sure, protein helps your abs and glutes look lean and ripped, but more importantly, the nutrient helps us remain healthy. "Protein is needed to keep our immune system running," says registered dietitian nutritionist Elisa Zied, MS, RD, CDN. "If you don't get enough protein from your diet, the proteins in your body that fight off invaders like bacteria and viruses will be broken down and used for fuel. This makes it more difficult for the body to fight infections so you might find that you experience more frequent colds and illnesses."

You're secretive about your diet

Woman craving junk food while on a diet

When you're trying to clean up your diet or lose weight, there's no need to post about it 24/7 on Instagram, but if you feel like you need to avoid the subject altogether because you're afraid you'll be judged for your super-strict regimen, you may be suffering from disordered eating. If you know deep down that your regimen isn't good for you, and you can't—or don't want to—change things up, you should seek help. The National Eating Disorders Association's website is a great initial resource.

Dana Leigh Smith
Dana has written for Women's Health, Prevention, Reader's Digest, and countless other publications. Read more about Dana Leigh