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The truth about fad diet plans
Published on October 17, 2023
Written by Health Loft
diet plan

What is considered a “fad” diet?

Have you ever seen the words keto, paleo, or whole 30 diet as you are scrolling through your social media feed? These eating styles or diet plans – what we call “fad diets”- may seem like harmless plans to achieve a healthier lifestyle, but unfortunately, they can have many hidden consequences that aren’t portrayed on social media. A “fad” diet plan is a way of eating that is popular for a specific period of time, usually alludes to rapid weight loss and promises many “health benefits”. These types of diet plans are usually promoting a low-caloric intake and completely wiping out one specific food group, which can potentially lead to nutritional deficiencies. The one thing that fad diet plans never disclose is, the “health benefits” you have been promised will quickly disappear once you stop the diet. Not to mention a fad diet can have damaging psychological effects on you after you restrict different foods for added “health benefits”.  

Are “Fad Diet Plans” Effective?

The quick answer is no – and they can be both physically and emotionally damaging. We often turn to the internet to find out the fastest way to achieve our health goals – and for many people that automatically translates to losing weight (and losing it fast). Though social media and your peers may say otherwise, the number on the scale does not determine your health and it will never be the answer to any insecurities that lie beneath the surface. If we lose weight too quickly it can have a damaging effect on our health. Some effects of rapid weight loss include losing water weight, lean tissue and muscle mass. Rapid weight loss can also increase your likelihood of getting sick and can be a cause of low energy levels. In this article, we will discuss different examples of fad diets and different types of diet plans, what each diet consists of, and how they can affect you nutritionally, physically, mentally and emotionally.

Ketogenic Diet Plan

What is it and how does it work?
The ketogenic diet is a type of diet plan that promotes a high fat, low carbohydrate eating pattern. This diet plan forces your body to use a type of fuel that the liver produces from stored fat, known as ketone bodies, instead of using the main source of fuel, glucose, that comes from carbohydrates. Eliminating a majority of carbohydrates from our diet can lead us to feeling foggy and forgetful. This is usually the case because carbohydrates are the brain’s main fuel source for energy.

What can I eat on the Keto diet? 
Due to the high fat requirement of the ketogenic diet plan, it is recommended that you consume a large quantity of fat at each meal. Although this diet does allow for unsaturated fats like nuts and avocados, it encourages you to consume a large amount of fats from saturated fats such as palm and coconut oil, butter, and lard. The ketogenic diet plan limits your fruit and vegetable intake because those tend to be rich in carbohydrates. It allows a small portion of berries and vegetable intake is restricted to leafy greens, cauliflower, broccoli, Brussels sprouts, asparagus, bell peppers, onions, garlic, mushrooms, cucumber, celery, and summer squashes. The protein guidelines are not very clearly outlined, meaning they do not distinguish between lean meats and proteins high in saturated fats.

Is the Ketogenic Diet Healthy?
This type of  diet  plan which is high in fat and low in carbohydrates is not recommended for anyone who has pancreatic disease, liver problems, thyroid issues, eating disorders, gallbladder disease or the removal of their gallbladder. A downside to this diet are the various health risks that come along with participating in this diet. Due to the high consumption of fat, it leads to many people often consuming  an unreasonably high amount of saturated fats in order to meet their individualized fat requirement. Researchers at the University of Chicago linked a high saturated fat intake to heart disease as well as many other serious conditions. This causes the liver to be overworked due to the high amounts of fat it needs to metabolize. 
By not consuming fibrous foods like fruits, vegetables and whole grains, you may have issues going to the bathroom and become nutrient deficient in vitamins A, C, and K as well as folate. Additionally, a low carbohydrate diet plan causes many negative physiological effects. This is the case because carbohydrates are the main source of fuel the brain uses to carry out daily tasks. Many people who have tried these diets report symptoms of irritability, confusion, dizzy spells, lack of sleep, and fatigue throughout the day due to the inadequate amount of carbohydrates your body is being provided with. It is important to provide your body with 45-65% of your diet with carbohydrates, which come from sources such as whole grains, fruit, pasta, beans and legumes, and starchy vegetables. 

The Paleo Diet Plan

What is it and how does it work?
Ever heard of the caveman or hunter and gatherer diet? The Paleo Diet is just another name for what might have been consumed during the Paleolithic era. This type of diet plan discourages eating food that became popular once farming was discovered such as dairy, legumes and grains. The idea is that we should be eating like our ancestors because it is aligned with our genetics and therefore good for our optimal health. This works in the same way as the keto diet plan. Your body is relying more heavily on protein than carbs. This diet also limits added sugars and processed foods, which include many “convenience” foods that are packaged, such as crackers, chips, granola bars, cereal, frozen foods and fast foods, which many Americans incorporate into their daily lives.

What can I eat on the Paleo diet?
The paleo diet consists of consuming fresh fruits and vegetables, lean meats, fish, eggs, nuts, and seeds. This type of diet plan wants you to avoid gluten and grain products, simple sugars, added salt, dairy, legumes and nightshades, and supplementation. It also advocates for the 85-15 Rule. This simply means that 85 percent of the time you should be eating “clean”, while the other 15 percent of the time you can indulge in the foods you enjoy. 

Is the Paleo Diet Healthy?
This diet can have a lot of healthy components to it, but can also cause you to miss key nutrients such as vitamin D and calcium from dairy sources that put us at risk of deficiency and in the long run will affect your bone health. Many times stress levels are increased because it can become very difficult to participate in any diet that restricts one or more food categories. Similar to the keto diet plan, it cuts out carbohydrates which are crucial for optimal brain function and overall energy levels.

Intermittent Fasting 

What is it and how does it work?
Intermittent fasting a type of diet plan which is a way of eating that is practiced by cycling between different periods of time when you are in a fasted and fed state. The three most popular approaches to intermittent fasting are alternate day fasting, 5:2 fasting, and daily time restricting fasting. Alternate day fasting is when you have a normal eating schedule for the whole day, and then the following day you fast completely or have less than 500 kcals for that day. 5:2 fasting is when you fast two days out of the week and the other five days you eat regularly. Lastly, the daily time restricting fasting is having an eight hour window to eat your food each day.

What can I eat when intermittent fasting?
There is no diet plan or foods to specifically avoid when you are intermittent fasting, rather when to eat them.

Is Intermittent Fasting Healthy?
Although this type of diet plan seems to incorporate all of the food groups: fruits & vegetables, whole grains, protein and dairy, there are many pitfalls when it comes to taking on this diet. Research has shown that after fasting for a long period of time, you become deprived of food and your hormones and hunger cues go into overdrive. This creates an unhealthy relationship with food because it is in our nature to reward ourselves and overindulge after we do something good for ourselves. Another reason people tend to try intermittent fasting, is the hypothesis that it helps boost immune function and reduce inflammation. Unfortunately, there has been no strong evidence that suggests that a fasting-based diet plan creates these suggested benefits. Limiting your caloric intake and skipping meals at regular times throughout the day is not recommended for anyone, especially people who have high blood pressure or heart disease. These diseases have medications that are more prone to electrolyte abnormalities from fasting. People who have diabetes should also not be partaking in the intermittent fasting diet plan because it creates a dangerous environment for your blood sugar levels. 

Whole30 Diet Plan

What is it and how does it work?
Whole30 is a type of diet plan that essentially is an elimination diet that emphasizes whole foods and unprocessed foods for a full 30 days. If you slip up or have “cheat day” you are required to start the process from the beginning. After the 30 days are up, you begin to reintroduce the foods that were eliminated in a specific manner in order to see how your body reacts to specific types of foods. This type of diet plan promotes a “healthier lifestyle” by eliminating pro-inflammatory foods like added sugar and processed foods. After the removal of these foods, you slowly reintroduce them back into your diet to see which foods might not be in agreeance to you and your body.

What can I eat on the Whole30 diet?
The whole30 diet plan states that you are allowed to eat meat, seafood, eggs, fruits and vegetables, natural fats, herbs, spices, and seasonings. Only a few legumes are allowed to be consumed which include green beans, snap peas, and snow peas. The foods that you are to completely avoid are added sugars (real or artificial), alcohol (not even for cooking), grains, legumes, dairy, carrageenan, MSG, sulfites, baked goods, and junk food. 

Is the Whole30 Diet Healthy?
While this type of diet plan encourages whole and unprocessed foods, it also suggests the elimination of grains and dairy all together. This makes it difficult to consume adequate sources of plant-based protein, calcium, and vitamin D. As mentioned earlier, the amount of carbohydrates we provide our body with affects our energy levels and brain function. This diet plan sets the mentality that all foods that contain sugar are bad for you. If you talk to a registered dietitian, labeling foods as “good” or “bad” is not something you should get into the habit of doing. It is okay to treat yourself to your favorite foods as long as you mindfully indulge. 

So where do I go from here?

The next time you are itching to start the new popular diet, take a deep breath and keep on scrolling. The first step in learning to eat healthy for you, is learning to walk away from anything that is labeled “___ diet”. Once you are able to commit to asking questions about your personal nutrition journey, refer to a dietitian to get advice on small ways to change your eating habits, how to practice intuitive eating, and how to incorporate a more balanced and healthier lifestyle, rather than opting for any type of diet plan that is hyped around you. In general, most of the population would benefit from the following recommendations from the website*:

  • Half of your plate should be colorful.
    • Eat different fruits and vegetables to provide a variety of vitamins and minerals to your diet. 
  • Make half your grains, whole grains. 
    • “100% whole grain” should be the first or second ingredient in breads, pastas, oatmeal, and snacks you pick out such as popcorn.
  • Mix of animal and plant-based protein.
    • Lean protein: seafood, eggs, chicken, and pork. 
    • Plant-based protein: beans and legumes, unsalted nuts and seeds, tofu, and eggs. 
  • Limit items high in sodium, added sugar, and saturated fats. 
    • Switch to vegetable oils instead of butter. 
  • Swap out sugary drinks for water.

*It is important to note that everyone has different nutritional needs, and it is important to speak with a health care provider during your journey to better health.

If you want to learn more about fad diet plans or learn what healthy eating could look like for you, talk to a Health Loft dietitian in person in Chicago, IL or virtually via our telehealth platform in various parts of the United States by calling us at (312) 374-5399 or by scheduling an appointment online.  For more tips and fun facts to also check out our Facebook, Instagram, and Twitter pages for more articles on nutrition, physical therapy, and exercise!

Written By Frankie Severyns
Edited By Alexander Franz
Reviewed by Morgan Murdock, RD.


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