Does the Special K Diet Work? Myth or Fact | Pros & Cons

Weight Loss & Diets | Written by Nathan Petitpas | Updated on 15 December 2021

A special K breakfast cereal box that has two arrows or situations shown from it. One case where a man is eating healthy and slimmed down his waist size after trying the special k diet. Then the other where a man is angry and wondering if the diet even works.

There are pros and cons to every diet, but does the Special K diet work? Many believe it’s a myth and even though this particular food trend began in the early 2000’s, many still wonder if it’s effective. There were countless Special K diet success stories during this time, but is there merit behind these results?

Diet news always comes with their perks and drawbacks, and the Special K diet is no different. While it boasts remarkable results, the cons may be greater than the pros, especially considering that permanent solutions should be the goal of any successful diet.

In this article, we will address what the Special K diet is, how it can benefit you, and dispel if it truly works.

Here’s everything you need to know about the Special K diet, and how it may be helpful or harmful to many dieting goals.

The Special K Diet: How it Works

Kellogg’s produces many different varieties of cereal, snacks, and other food goods. They have done this since their inception in 1906- their products are arguably a mainstay for many families across the United States.

In 1955, Kellogg’s created Special K, a grain-based cereal available in a variety of flavors. It wasn’t until 2004 that the Special K Challenge was born and became big news. This diet trend boasted that dieters could lose enough weight in two weeks that would merit purchasing one size lower in pants- there were many images of Special K diet results before and after. You could see the results in people; it does work, in theory.

This particular diet only had a few specific guidelines: those participating in the diet would replace their usual breakfast and lunch with one serving of Special K cereal, and eat whatever they wanted for dinner. Those trying the Special K diet were allowed healthy snacks throughout the day, and these often included other Special K products from Kellogg’s.

The main premise behind this alteration in the average eating schedule is simple: choosing a serving of cereal instead of a high fat or high calorie breakfast and lunch should result in weight loss

This is a fair expectation, given that the average calorie count in a serving of Special K is 120-140 calories per 1 cup of flakes. [1] This is going to be far less than the average consumer’s breakfast or lunch choice, especially if they don’t normally consume these meals at home.

This type of diet plan incorporates portion control and low calorie foods, which is a popular trait in many diets. These types of diets often have the most positive results in obese or overweight adults rather than average weighted adults and link to many other benefits.

This makes Special K a good choice for those struggling with their weight and weight troubles. Choosing a low calorie cereal over a more higher calorie meal can easily result in weight loss results you can see, especially in a body unaccustomed to lower calorie choices.

More About Special K

Special K cereal also boasts many vitamins and minerals, including the following valuable selections:

  • Iron
  • Folate
  • Vitamin B6
  • Vitamin B12
  • Thiamin
  • Niacin

While the cereal has an average amount of sugar in it for most breakfast cereal (about 11 grams), it also contains a fairly low amount of fiber (3 grams). Critics of the diet cite this amount of fiber as insufficient, especially when fiber has been proven valuable for long-term weight loss. [2] But more on that later.

Kellogg’s also offers a wide variety of snacks designed to help you cut calories. These snacks are recommended in tandem with the Special K weight loss challenge, due to their low calorie count and overall ease of consumption.

Some of these snacks include:

  • Breakfast shakes
  • Crackers
  • Popcorn
  • Granola bars
  • Cereal bars
  • Cracker chips

The diet also recommended consumers create their own unique recipes using Special K cereal. Otherwise, there were no other rules or guidelines. By simply replacing breakfast and lunch with a cup of cereal and skim milk, dieters were told they could lose a pant’s size in two weeks.

Does the Special K Diet Help You Lose Weight Fast?

There is criticism and speculation surrounding the Special K diet, mainly regarding the simple fact of: does the Special K Diet work? Choosing cereal for two out of three meals a day could mean that you lose weight fast, but was this the case back in 2004? 

A study was performed by Kellogg’s through Loughborough University. This study monitored participants over a two week period, just like the diet suggests. Participants in the study were required to follow the diet, meaning they replaced two meals per day with Special K cereal and were allowed their own unique dinner and low calorie snacks.

The study resulted in 75% of participants showing decreased hip and waist measurements. [3] While this was concluded to be primarily loss in fat, it does indeed illustrate that the Special K diet does help dieters shed some pounds quicker than other methods.

However, what does this mean in the long term, as a two-week weight loss regimen isn’t ideal for most healthy individuals in the long run? While this cereal can be a valuable meal replacement for a brief period of time, that is the primary purpose of the Special K diet: a way of jump-starting your weight loss journey rather than becoming the only way you lose weight.

This isn’t to say that using this cereal won’t be beneficial for losing weight or altering your eating habits. It could be a useful tool for many hoping to achieve pound weight loss right off the bat without altering their exercise routine or other eating habits. Let’s take a look at how Special K can be used for weight loss.

Cereal and Recipes for Weight Loss: Using Special K

Without wanting to alter a usual diet and health routine too much, cereal can be a perfect fit for dieters searching for an easy start. That is part of what made the Special K challenge so appealing: substituting cereal for heavier meals is easy for most consumers to do.

Using Special K or another brand of cereal to help with trimming any excess pounds can be beneficial, especially if cereal is directly replacing unhealthy meal choices. Given that cereal has many vitamins and minerals in such a low calorie package, there are many benefits to it.

Cereal has been directly linked to forming healthy diets and dieting habits, given it is a convenient and nutrient dense food. [4] Many people who consume cereal as a part of their daily meal plan have positive results, whether it be weight loss or improved mood.

Using Special K can work for losing weight and trimming excess fat in the body, especially if the person dieting is not making many other health conscious choices in their life. Cereal is even linked to a lower risk of both diabetes and hypertension, a perk for many consumers.

However, does this mean that the Special K challenge is the best way to utilize cereal in order to go down a pants size? Not necessarily

Cereal can be a great snack to use at home, especially when used in other recipes or as a convenient treat for a busy lifestyle. Creating recipes using Special K is encouraged by Kellogg’s, and many consumers followed the company’s advice, incorporating these grains into many unique meals and recipes.

But eating two servings of cereal a day isn’t a bad thing on its own- so long as eating these two servings isn’t eliminating the opportunity to consume potentially healthier meals. Choosing cereal over a few cookies? That is a good idea. Choosing cereal over a lightly dressed salad? That’s a different story.

Cons of the Special K Diet

While the Special K weight loss program produced results that were in line with what consumers wanted, there is much to be considered before beginning their weight loss plan. Many questions have arisen with this fad, such as how healthy it is overall, and if it even works. Has anyone done the Special K diet recently?

Much like many diet trends and fat burning supplements, the research did not hold up for consumer’s health beyond the first two weeks. This is the primary con to many cereal diets: dieters may lose a healthy amount of weight for a brief period of time, but the plan should not be continued after two weeks.

Asking if this plan works is difficult. It seems to yield results for the first two weeks, just like Kellogg’s advertises. However, cereal as a meal replacement should not be something that consumers choose, week after week, month after month.

Cereal is not a very filling meal either- it is not uncommon for dieters to report irritability and mood swings while consuming such a low amount of calories. [5] Because that is what this diet suggests: cutting calories will help you lose weight, but there are long-term cons.

Some of the primary cons of the Special K diet include:

  • Difficulty adjusting to low calorie count
  • Irritability and mood disruption
  • Dizziness and fatigue
  • Lack of nutrients found in other food
  • Difficulty maintaining the diet for long periods of time

While having the ability to lose weight while only consuming cereal may seem like a positive, it should not be someone’s priority. Choosing cereal over other unhealthy snacks may be beneficial, but choosing a more comprehensive and nutritious meal instead of cereal can lead to healthy weight loss and an overall improvement to consumer’s health.

The Special K challenge works for those of you seeking diets that only work short-term, and it is not recommended for use beyond the initial two weeks. 

“Does the Special K Diet Work?” FAQs

Many people have continued questions about this particular diet, even today. New diets have emerged with more evidence for weight loss, but the Special K plan still raises questions from time to time. Here are some of the top questions asked about this cereal diet.

Is Special K Good for Weight Loss?

Yes and no. Consuming cereal in place of other meals can be valuable for adults currently trying to adjust their diet and consume fewer calories for weight loss. Do you want to lose weight quickly? Do you want a simple solution for losing weight? The answer will most likely be yes. However, this does not necessarily mean Special K’s success works long-term.

WebMD illustrates a typical meal plan for the Special K diet, as well as what potential perks there might be to this program. [6] While participants in this diet show weight loss after two weeks of dedication, it is always a short-lived victory.

Ultimately, it depends on someone’s own unique weight loss goals and vision in order to determine whether or not this cereal is actually good for weight loss. This diet can work to help adults shed some pounds, but it should not be a permanent solution for anyone.

Some permanent solutions for weight loss may include:

  • Reduced portion sizes
  • A rigorous exercise routine based on age, weight, etc.
  • Healthy food choices, such as more fruits and vegetables
  • Knowing the current status of your overall health
  • Making healthy substitutions, such as whole grains over processed grains
  • Choosing foods that are high in dietary fiber
  • Dedication to your new diet plan

Many studies have also proven that cutting calories and reducing caloric intake over a long period of time may in fact not be beneficial to our health. [7] This is especially true if dieters are choosing a sugary cereal as a meal replacement.

Sure, it might be good short term to lose weight, but being in an extreme calorie deficit for too long may be harmful. Some weight loss programs such as the such as the dr nowzaradan diet plan limits individuals to 1200 calories (to prepare for surgery), but is suggested to not be used longer than 2 months or without the supervision of a professional. 

So, choosing Special K’s diet plan may result in some weight loss, at least initially. However, making more holistic changes to one’s diet will result in lasting effects and fewer side effects that come with extreme calorie deficits or long periods of deficits. 

Will I Lose Weight Eating 2 Bowls of Cereal a Day?

While Special K boasts weight loss results from eating two bowls of cereal a day, it is a leading phrase to assume that one will lose weight by simply eating two bowls of cereal each and every single day.

For example, this suggests that one could consume two bowls of cereal in addition to whatever else someone might be eating, rather than substituting a bowl of cereal for a particular meal or snack. Special K’s products advertise meal replacement, not adding additional cereal to your current diet.

However, choosing whole grains over other more harmful snacks or meals isn’t a bad idea. Plus, the average serving size for whole grain cereals can make a low calorie meal or treat for many people.

There is no guarantee anyone will lose weight on any diet plan. Every single body is different, and all metabolisms process food and exercise differently. Eating two bowls of cereal a day may result in weight loss; it may not.

Which Cereal is Best for Weight Loss?

While Special K offers an entire diet plan alongside their products, does that mean it is the best cereal for weight loss? Many nutritionists and evidence suggests otherwise, as there are many other cereals packed full of more dietary fiber and nutrients than this well-known Kellogg’s brand.

With so many cereal options on the market today, it can be difficult to know which one in particular is best for weight loss. There are no doubt many options that may assist with health goals, especially if someone is searching for a cereal with added vitamins and minerals.

Cereal has been known for having the following benefits, not just weight loss [8]:

  • Added vitamins and minerals, including iron and folate
  • High fiber content which promotes weight loss
  • Whole grains
  • Low sugar content (in some cereals)
  • Cereal has many flavors and options, making it an accessible snack

Finding a cereal that is perfect for weight loss is possible, though the process may take some time. With many healthy options available on the market today, consumers have no shortage of options. However, some adults may be searching for a particular style of cereal, or perhaps certain health benefits.

For example, some cereals boast added vitamins but counteract the taste with higher sugar content. Some cereals may taste delicious, but lack adequate amounts of dietary fiber and whole grains. There is a trade-off to any product, especially when it comes to losing weight.

Keeping an eye out for organic or health conscious products may help someone searching for the best cereal for weight loss. Reading the nutrition facts and making note of the fiber content versus the calorie count could also assist in finding a cereal that works for losing weight fast.

It may also help to consider cereal in place of other higher calorie snacks, rather than as an end-all, be-all for losing weight. For example, choosing a cup of whole grain cereal as an afternoon snack instead of purchasing a processed snack from your local convenience store will make a difference over time.

Can Eating Just Cereal Make You Lose Weight?

Choosing a diet that consists solely of cereal may make you lose weight. However, does this make it a good diet or choice for a healthy adult? The answer is simply: no, because cereal cannot provide everything that a healthy body needs.

Special K can be a part of a healthy diet and exercise routine. It should never be the only thing that a healthy individual consumes, as cereal does not contain enough for any one person’s metabolism or overall health, especially when considered a long-term solution.

Choose to eat cereal over heavily processed foods, foods that are high in fat, and as an occasional meal replacement may make you lose weight. Cereal is certainly better for eating than fast food or other greasy choices. But it is not enough to eat all by itself, for every single meal and snack.

Choosing a diet that is varied and comprehensive is one of the easiest ways to lose weight. Plus, choosing to eat a variety of foods will keep the average adult from growing bored of their current diet and exercise routine. Consuming a single food, day in and out, may grow monotonous quickly.

Speaking of exercise, combining a detailed diet plan with an efficient exercise routine can help healthy adults reach their weight goals faster. Even taking an hour walk once per day can result in weight loss and improved mobility.

It is also more than possible for a body to plateau, or stop losing weight when it is only being fed the same foods. This is also the case if someone performs the exact same exercise day after day. The body is an adaptable machine- giving it variety often results in the most success, whether it be through diet or exercise.

Final Thoughts on Special K

While there is much evidence that points to the positive, this type of cereal based diet is not meant to be performed long-term. However, the basic principles can be applied to any diet: cutting calories and choosing to eat foods that are high in fiber can help you lose weight.

Many consumers can learn from this program and take its concepts further, into their own lives and in a healthy way that works for them. Cereal can make for a health-conscious breakfast and even a snack. But take the time to plan more nutritious meals, and incorporate an exercise regime into your life. This is how to lose a healthy amount of weight in the long run; you don’t have to ask “does the Special K diet work” any longer.


[1] SmartLabel. 23 October 2021. Kellogg’s Special K Red Berries Cereal. 25 October 2021. Web.

[2] Miketinas, Derek. 1 October 2019. Fiber Intake Predicts Weight Loss and Dietary Adherence in Adults Consuming Calorie-Restricted Diets: The POUNDS Lost (Preventing Overweight Using Novel Dietary Strategies) Study. 25 October 2021. Web.

[3] Hooper, R. 2002. Body Shape and clothing size changes following Kellogg’s “Slimmer Jeans”. 25 October 2021. Web.

[4] Williams, Peter. 1 September 2014. The Benefits of Breakfast Cereal Consumption: A Systematic Review of the Evidence Base. 25 October 2021. Web.

[5] Martin, Corby. 1 June 2016. Effect of Calorie Restriction on Mood, Quality of Life, Sleep, and Sexual Function in Healthy Nonobese Adults. 25 October 2021. Web.

[6] Zelman, Kathleen. 2009. The Special K Challenge. 25 October 2021. Web.

[7] Benton, David. 28 June 2017. Reducing Calorie Intake May Not Help You Lose Body Weight. 25 October 2021. Web.

[8] Melanson, Kathleen. September 2006. Consumption of whole-grain cereals during weight loss: effects on dietary quality, dietary fiber, magnesium, vitamin B-6, and obesity. 25 October 2021. Web.

About the Author

Nathan Petitpas

Nathan has been a fitness enthusiast for the past 12 years and jumps between several types of training such as bodybuilding, powerlifting, cycling, gymnastics, and backcountry hiking. Due to the varying caloric needs of numerous sports, he has cycled between all types of diets and currently eats a whole food diet. In addition, Nathan lives with several injuries such as hip impingement, spondylolisthesis, and scoliosis, so he underwent self-rehabilitation and no longer lives with debilitating pain.