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The topic around food and what one should be eating to look and feel their best is beyond complex. It will, of course, differ from person to person and will have to be catered to the individual. Our bodies respond to diets and foods differently, but should we be considering a fad diet or a low-calorie diet? What do we need to know about each of them? Let’s find out…

Fad diets vs. low-calorie diets

What do each of these diets entail, and how are they different?

Well, fad diets are eating plans that are often advertised as the “best” or “fastest” way one should go about losing weight. They do well at sounding like newly discovered information and hacks that promise a better and healthier you.

Fad diets normally involve cutting out certain foods, banning entire food groups, or overselling the benefits of a particular food. Fad diets are based on very little or incorrect research, if any. The fad diets that celebrities and social media influencers rave about, the ones that promise to “rid belly fat fast” or “lose 10 pounds in a week” are neither safe nor realistic.

A low-calorie diet is said to work in the way that you eat fewer calories and therefore lose weight. At a basic level, these diets aim to restrict your calories to promote weight loss, says nutritionist Jessica Cording, RD.

The exact number of calories you can have on a low-calorie diet varies, but it usually “involves eating 800 to 1,200 calories per day to lose weight,” says Samantha Cassetty, RD. While everyone’s calorie needs are different, the Dietary Guidelines for Americans recommends that people get between 1,600 and 3,000 calories per day.

How is a fad diet different from a low-calorie diet?

A fad diet is different from a low-calorie diet in that it is a marketing scheme that promises unrealistic outcomes and is not based on a well-balanced diet that promotes long-term health. A low-calorie diet is a diet that provides a moderate amount of calories that can help with weight loss and maintenance.

A fad diet is often short-lived and can have negative effects on your health, while a low-calorie diet can be sustained and beneficial but not necessarily for long-term use.

How to spot a fad diet

It can be confusing if the advice you are receiving is a fad diet or healthy advice that you should listen to. These clues scream fad diet.

  • Recommendations that promise a quick fix
  • Claims that sound too good to be true
  • Simplistic conclusions drawn from a complex study
  • Recommendations based on a single study
  • Dramatic statements that reputable scientific organizations refute.
  • Lists of “good” and “bad” foods
  • Recommendations made to help sell a book or product
  • Advice based on studies published without peer review.
  • Guidance from studies that ignore differences among individuals or groups
  • Elimination of one or more of the five food groups (fruits, vegetables, grains, protein foods, or dairy)
  • Diets that include testimonials.

“Oftentimes, fad diets will be based on some bit of information learned in research but will exploit it to such an extreme that it’s no longer scientifically sound,” -registered dietitian Maxine Smith, RD, LD.

Why fad diets are bad for you

Fad diets are not sold as a healthy lifestyle change but rather a DIY, quick, and easy weight loss secret. But this will leave you lacking essential nutrition. Fad diets don’t take into account the full range of vitamins and minerals your body needs. Fad diets promote eliminating foods that contain vital nutrients to maintain good health.

Cutting out nutrients can leave you at risk of developing serious health issues. On the other hand, fad diets will also over emphasize foods, which can also be problematic.

Fad diets propose a temporary solution that, for many people, is a lifelong challenge, which is weight loss. Once you stop the diet, any benefit gained (if any) is lost. Fad diets don’t incorporate other healthy-living modifications, like exercise, improved sleep habits, or stress reduction. Once you stop following the diet, your weight returns to where it started.

“Fad diets that emphasize weight loss may help you shed a few pounds for a little while. But the lost weight is usually regained quickly,” Maxine Smith, RD, LD, notes. “That’s because fad diets don’t focus on lifestyle modification, which is necessary to keep weight off, and these diets aren’t sustainable throughout life.”

What to know about a low-calorie diet

Technically, you can eat anything on a low-calorie diet, as long as your overall calorie intake is low. However, you should still make healthy choices to try to get the most nutrition out of your calories while staying satiated. You should focus on eating protein, healthy fats, and fiber. And overall, nutritious low-fat meals. Foods like these are filling and will help stabilize your blood sugar. When your blood sugar is stable, this equals better energy and mood.

Incorporating protein into each meal and snack will also help maintain muscle tissue, which can often decline on a low-calorie diet. It’s also important to prioritize whole foods!

If you are trying to eat to a specific calorie level, it may be helpful to track your food using an app-based tracker like Cronometer or MyFitnessPal. These sorts of apps can also help you monitor your nutrient intake, such as how much fiber or protein you eat.

Fill up on these foods when on a low-calorie diet

  • Lean meats
  • Nuts and seeds
  • Non-starchy vegetables like broccoli, spinach, and cucumbers
  • Fruits
  • Whole grains
  • Foods with healthy fats, like avocado and fish

How effective are low-calorie diets for weight loss?

Research has consistently shown us that reducing your calorie intake can lead to weight loss, but as we all know, people’s bodies are different. It is, therefore, difficult to tell how a low-calorie diet will impact someone in the long term.

“There’s evidence that a low-calorie diet can help with short-term weight loss, but 80 percent of people who lose weight will regain it due to metabolic changes that stall weight loss and promote weight regain,” Samantha Cassetty, RD, says.

Unless you continue to eat the same number of calories, you’ll gain the weight back if you stop following this diet. “This can lead to stress and feelings of shame and guilt. So, if you lost weight with a low-calorie diet and then gained it all back, I wouldn’t consider the diet effective,” says Cassetty.

How to safely lose weight

Rather than jumping into the latest trend in dieting, sticking with tried-and-true (and evidence-based) weight loss and healthy living advice is always the right way to go. Namely:

  • Eat a variety of unprocessed or minimally processed foods
  • Fresh fruits and veggies should take up about half your plate at every meal
  • Stick to moderate portion sizes
  • Exercise regularly
  • Keep your stress levels manageable
  • Get plenty of sleep
  • Drink enough water

Listen to your body

Often times we don’t pay attention to what our bodies are telling us. We end up wasting time on a new diet that doesn’t work for our bodies. Find what’s right for you. If you’re unsure whether the diet and eating advice you’re getting is healthy, talk with a healthcare provider, like a primary care doctor or a registered dietitian. They can help you follow an approach to healthy eating that meets your goals.

Plant based diet – Natures Store (
Tamlyn Bingle

Tamlyn Bingle

With an ever growing interest and appetite for sustainability, Tamlyn Bingle is an ambitious writer, her objective is to always share knowledgeable and insightful information in the written space. Tamlyn also enjoys living a healthy and active lifestyle, appreciative of nature and all creatures great and small.


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