These Are the 7 Worst Diet Mistakes For Weight Loss (That Can Actually Cause Weight Gain!)

Many people focus on what they can't have when they're trying to lose weight, such as carbs, bread, sugar, alcohol, or dessert. "When they completely avoid foods they love, they inevitably feel deprived, which can lead to overindulging later on, sabotageing their weight-loss efforts," explained registered dietician Rachel Stahl, MS, RD, CDN, CDE, owner of Rachel Stahl Nutrition.

Registered dietitian Lauren Smith, MS, RD, LDN, founder of The Sorority Nutritionist, agreed. "Cutting out entire food groups is not how you sustainably lose weight," she said, "and in fact it sets you up for failure." She added, "That's because you always want what you can't have, and when you put a food as 'off limits' and never allow yourself to have it, when the time comes around that you do eat this food, you're more likely to overeat it and feel guilty."

There is no one "good" or "bad" food, and Rachel and Lauren agreed that moderation is key! Learn to incorporate all foods into your balanced diet. Lauren added, "You don't have to cut out sweets, carbs, or any one food to lose weight. As long as you eat in a calorie deficit, you will achieve your results."

"Eating too little for too long" is a mistake registered dietitian Leslie Langevin, MS, RD, CD, author of The Anti-Inflammatory Kitchen Cookbook, sees with clients. Aside from constantly making you feel hungry and irritable, Rachel and Lauren both agreed and explained that this can send signals to your body to conserve calories which lowers your metabolism, making weight loss nearly impossible.

While Lauren explained that a moderate calorie deficit will help you lose weight, Leslie warned, "Never eat below your resting metabolic rate (the calories your body burns at rest) for a long period of time." Lauren said that the "average female has a resting metabolic rate of 1,000 to 1,400 calories per day." If women follow strict diets and drastically cut down on calories and fuel below their RMR, it puts their bodies into a state of starvation, Lauren explained.

While weight loss can be quick when severely cutting calories, it doesn't last and your metabolism slows down. You can lose muscle and many women just regain the weight after. Leslie has had patients who have eaten so little for so long, that they could be eating fewer than 1,000 calories per day and not lose weight, which is very frustrating!

Rachel added that not eating enough could also result in depriving your body of important nutrients. "Eating well-balanced meals and snacks, with an emphasis on protein, healthy fats, and fibre, helps keep my clients satisfied and their energy levels up — no calorie counting required." Leslie said to meet with a registered dietitian to get a good calorie recommendation before you cut out too much food. In general, it is advised not to go below 1,200 calories a day for women.

Just because a food is listed as "low-fat," "no sugar," or "diet" doesn't necessarily make the product healthy, Rachel said. These foods may have fewer calories, but they often contain added preservatives, salt, and sugar to make up for the flavour. "I often find my clients not feeling satiated when eating these foods, which can hinder their weight-loss goals," Rachel said.

She recommended focusing on whole foods like fruits, vegetables, whole grains, legumes, nuts, and seeds rather than processed foods like sugary snacks and beverages.

Diets don't work. Period. Cutting down drastically on calories, cutting out food groups or the foods that you love, or setting strict rules about when you can eat is impossible to stick to long term, Lauren said.

Find ways to slowly reduce calories without feeling deprived. Eating more veggies, fruits, and other whole foods is one way to do that. Look up healthier alternatives to your favourite not-so-healthy recipes. And don't limit your favourite foods entirely; make them part of your balanced diet.

Lauren said that "before you go on a diet, ask yourself, 'Will I be able to stick to this long term?' If you wouldn't be able to give up a food for the rest of your life, that diet is BS and not good for you!"

"When you realise you have a few weeks before a big event, such as a high school reunion or holiday party, that's when women tend to freak out and want to lose weight so they can feel their best. And I get it!" Lauren said. But reality is, if you've struggled with your weight for years, how do you expect to magically transform your body in a matter of a few weeks?

Lauren said that women need to learn to give themselves more time when making a lifestyle change to lose weight and gain confidence. "You can achieve any goal you set for yourself, but you also have to be realistic with yourself," Lauren said. "Results that really last don't happen overnight."

Be warned that diets that promise quick weight loss don't work, and neither does drinking skinny tea or taking a magical fat-burning supplement — that's not how you achieve weight loss that lasts. "Instead, you have to put in the work over months and show up for yourself every day and you'll get there! And it will be so much more worth it," Lauren said.