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How FAD Diets Are Stopping You From Relieving IBS

This is a slightly unusual post for me as I usually stay away from weight loss topics. The reason? I believe there are a lot of other factors that we can work on to improve our overall health and well-being and a number on a scale is just a very small piece to the puzzle and an overly simplistic way of categorising our health status.

In saying that, this time of year is usually associated with people looking to make a change to their weight, eating habits and/or lifestyle. All you have do is a quick Google search for “how to improve my gut health” or “best weight loss diet” and it will come up with an endless amount of fad diets.

What’s not often spoken about is how these diets may be affecting our gut health in Irritable Bowel Syndrome (IBS). In this blog I will share with you the impact that fad diets can have on your gut health and IBS and my expert tips for spotting a fad diet.

What is a Fad Diet?

Fad diets are diets that become popular quickly. They can also be called a popular diet or a diet cult. They offer quick fix solutions and promises of weight loss or other health benefits that are not scientifically proven. They are usually highly restrictive and eliminate either whole food groups (particularly grains or dairy) or a combination of different foods. This usually results in rapid short-term weight loss; however, most do not lead to keeping the weight off long-term. They often offer expensive and unnecessary supplements or food products, such as shakes, in place of the eliminated foods.

They can be difficult to stick due to their restrictive nature and therefore most people end up craving the foods they have been missing which leads to over-eating, usually on less healthy options, and weight regain. Unfortunately, many aim to take advantage of people who may have a history of yo-yo dieting, wanting to change their appearance, lose weight or improve their health.

Detox Diets

Detox diets have grown in popularity over recent years. These diets are another form of fad diet. They are usually a short-term diet, but this can range from days to months. They claim to eliminate harmful toxins from your body and provide your body with nutrients. They also claim to improve digestion, energy, hair, skin and nails as well as quick weight loss, boosting your immune system and getting rid of cellulite. Detox diets can include supplements, teas, herbs and colon cleanses. The whole idea of detox diets has no scientific basis. Our body is amazing and does a fantastic job of detoxing and removing waste and toxins from it, all on its own, via our liver, kidneys, lungs, gut and even skin.

Common Fad & Detox Diets

There are countless fad and detox diets currently available, so I am unable to cover them all, but I will briefly discuss the most common ones that I get asked questions about the most from my clients.

Paleolithic (Paleo) Diet

The Paleo diet is based on the notion that we should only eat foods that were available to our ancestors as our genetic makeup is more suited to hunter-gather paleolithic foods than our modern diet. It claims to improve our overall health and “cure” diseases such as diabetes, obesity, heart disease, osteoporosis and cancer. It includes meat, poultry, seafood, nuts, non-starchy vegetables and fruits. However, eliminates grains, dairy, legumes and processed foods.

The evidence supporting this diet is based on limited anthropologic (which is the science of humans, particularly their ancestors, cultural and physical development) findings. Although we don’t have very much research on the topic, the research we do have shows that those in the paleolithic era ate varied diets based on plants and game meats, which included grains and legumes, along with a variety of other plants. However, this is often not acknowledged by those supporting the diet.

This diet eliminates foods that are important sources of nutrients which are proven to decrease our risk of developing chronic diseases, which the diet claims to “cure”. These include prebiotics and fibre which are vital for gut health and also help lower cholesterol and calcium which is essential for preventing osteopenia and osteoporosis.

Autoimmune Protocol (AIP) Diet

The AIP diet is often referred to as a stricter version of the paleo diet. It’s based on the principle that a “leaky gut” is the cause of all autoimmune conditions.

Before I go any further, I think it’s important to address the term “leaky gut”, I hear this get thrown around so often lately and is blamed as the underlying cause of all gut health issues, particularly in the alternative health space. However, this is not something you will hear an evidenced-based health or medical professional diagnosis you with. Why? There is no standard definition on what leaky gut actually is and there are no reliable or clinically proven tests to diagnose it. It actually refers to something called intestinal barrier dysfunction. In a normal healthy gut, there are things called tight junctions. These hold the cells that line the gut together and help prevent things that may be harmful from passing from the gut into the body. If or when leaky gut does occur, it as a result of another condition, such as coeliac disease, inflammatory bowel disease (IBD) or gut infections, which cause inflammation in the gut and can damage these tight junctions.

Of course, it you do a quick Google search on “how to heal a leaky gut” it will come up with endless treatments such as special diets and gut health supplements. The truth is that there just aren’t any treatments for leaky gut and there is limited scientific evidence supporting any of these treatments. So, I would recommend that you save you money.

So now that we have addressed leaky gut, let’s get back to the AIP diet. As with the paleo diet it mainly includes meat and vegetables and is incredibly restrictive. You are usually required to follow this diet for several weeks before you can introduce other foods.

Due to it being so restrictive, it can be difficult to follow, particularly as it can significantly impact your day to day life. It is also important to remember that there is no one size fits all approach when it comes to food and nutrition and managing autoimmune conditions. There has also only been 1 scientific paper published on the AIP diet, which was conducted on a small group of only 15 people with IBD, had no control group and was not randomized, so was not a good quality scientific study. There are currently no conclusive clinical studies on the role that diet plays in leaky gut and autoimmune diseases. Although diet can play a role in inflammation, it is not the only strategy that can be used, therefore it’s incredibly important to speak to your doctor or a dietitian about dietary and lifestyle changes that can be made to assist with improving inflammation.

Ketogenic (Keto) Diet

Ketogenic diets were first discovered to show benefits in managing children’s epilepsy and have been around for over 100 years. Although these diets are still used to treat epilepsy in children, they have recently gained a lot of popularity for their supposed benefits for managing a variety of other conditions including type 2 diabetes , obesity and heart disease. As the name suggests, they aim to get your body into ketosis, which occurs when there is a lack of glucose in your body for your body to use as energy. This then uses your bodies fat stores to create ketones, which can be used as energy.

What’s important to mention is that, unlike for the use in children with epilepsy, there is no one single definition or evidenced based guidelines for what the ketogenic diet is or how it should be implemented. All the studies that have been conducted used different macronutrient quantities, so different fat and carbohydrate ratios, went for different lengths of time and used different types of people in their studies. Therefore, being able to say exactly what the modern-day ketogenic diet is and how it should specifically be implemented and followed in near impossible.

Despite its claims studies have shown that, when compared to a low-fat diet, the ketogenic diet does not result in clinically significant weight loss after 1 year. Although the diet can improve HDL or “good” cholesterol and triglycerides, it also increases LDL or “bad” cholesterol which can increase your risk of cardiovascular disease (CVD). No benefits or improvements were also seen on blood pressure, insulin sensitivity or HbA1c levels (this is a blood test used to determine your average blood sugar levels over 2-3 months).

There are also several side-effects that are associated with the ketogenic diet including constipation and/or diarrhoea (which are symptoms we aim to eliminate in IBS), headaches, muscle cramps, bad breath and fatigue. People also find it difficult to stick to the diet over the long-term.

Gut and Psychology Syndrome (GAPS) Diet

The GAPS diet is a strict elimination diet that is based on animal fats, meat, fish, eggs, probiotic foods and vegetables. It eliminates grains, pasteurised dairy, starchy vegetables and refined carbohydrates and requires you to take several different supplements. The full GAPS diet goes for 1.5–2 years. It claims that conditions affecting the brain are caused by a leaky gut. It is promoted as a natural “cure” for neurological conditions including autism, ADD and ADHD, depression, bipolar disorder and eating disorders. It also claims to be able to help children with food allergies and intolerances.

There is currently no scientific evidence to support any of the claims made by the GAPS diet. Any supposed benefits from the diet are solely based on testimonials. It is a very restrictive diet that is required to be followed for a long period of time, which makes it hard to stick to. It is also recommended for young people, which it can be particularly harmful for, and puts them at risk of malnutrition. Those with autism may also not as readily accept new foods or modifications to their diet, due to these reasons they may already be on a restrictive diet to start with. Restrictive diets are also not recommended for those with eating disorders, which this diet claims to cure. If you are considering this diet please seek the advice of your doctor or dietitian.

Celery Juice

This has become really popular over the last 12 months or so and is one that my clients as me about quiet frequently. It claims to repair gut damage, improve digestion, detoxify your gut and body, decrease inflammation, help with constipation, get rid of leaky gut, decrease bloating and wind, balance blood pH and decrease your risk of developing conditions such as high blood pressure and cancer. Having celery juice is fine as, like other vegetables juices, it does contain vitamins and mineral, but all the claims that it can detox the body and “cure” a variety of conditions particularly in regard to gut health are not evidence based or scientifically proven.

Juicing celery also removes most of the fibre, which are prebiotics that help to keep our gut happy and support a healthy gut microbiome. It’s also often recommended to people with IBS to “cure” their symptoms, but celery is actually high in the FODMAP mannitol. FODMAPS are well known and scientifically proven to cause gut symptoms in those with IBS and are usually limited on a FODMAP diet. In additional, multiple stalks of celery are needed to make the juice, this means that people are likely to consume a much larger amount of mannitol which can cause bloating and painful wind. The compounds in celery juice can also increase the side effects of some medications and stop them from working properly. These include blood pressure and anti-anxiety medications.

The Effect on Your Gut Health

What is the Gut Microbiome?

The human gut has a hundred trillion micro-organisms living within it, which are mostly bacteria. These are referred to as the gut microbiota. Whereas, the microbiome is the combination of all the genetic material of the microbiota. The gut microbiome is very complex, and everyone has a very unique microbiome. The diversity and amount of these bacteria increase throughout the gut from the stomach, to the small intestine and then large intestine or colon. Did you know that your colon has the most amount of gut bacteria?

Factors that determine and influence our gut microbiome include our diet, lifestyle, genetics and environment. For example, the way that we were born, caesarean section vs vaginal birth, the diversity of gut bacteria is lower in infants born via caesarean section and the composition of their gut microbiome is different to those born vaginally. Our diet significantly affects the makeup and diversity of our gut microbiome and accounts for around 57% of the changes seen in our gut microbiota. The composition of our gut microbiome can begin to change in as little as one day after changing our diet. This means that our diet has huge potential to make positive changes to our gut microbiome which are associated with improvements to our health.

Effects of the Gut Microbiome on Our Health

Research shows that our gut microbiome effects both our physical and mental health. Changes to the composition of the gut microbiome have been associated with a number of chronic diseases including CVD, type 2 diabetes, IBD, autoimmune diseases, overweight and obesity and some skin conditions such as psoriasis.

It is also believed to regulate the gut-brain axis which is how your gut and your brain communicate with each other. Research suggests that a disturbance and reduced diversity of gut bacteria can have a link to increased feelings of anxiety and depression, due to less serotonin and dopamine being produced. It can also impact our overall mood and appetite regulation.

Our gut microbiota, particularly in the colon, breaks down or ferments the nutrients that we have eaten in our diet. These are mainly certain types of carbohydrates called fructans and fibre. These are also known as prebiotics and produce short-chain fatty acids (SCFA). These help to protect our gastrointestinal tract, speed up repair of any damage in our gastrointestinal tract and reduce inflammation.

The Effect of Fad Diets on Your Gut Health & Overall Health

As I mentioned above, these diets often remove whole foods groups and cut out key nutrients which have been proven to decrease our risk of developing chronic diseases. This can result in a variety of symptoms including;

  • Dehydration

  • Constipation

  • Lethargy and fatigue

  • Confusion or difficulty concentrating

  • Inadequate intakes of vitamins and minerals, resulting in an increased risk of nutrient deficiencies.

Removing whole food groups also limits our intake of prebiotics and fibre which are important for keeping our gut microbiome healthy and happy. Prebiotics are known for promoting diversity in our gut which assists with improving our overall gut health. Adequate fibre intakes have been shown to decrease our risk of developing chronic diseases such as bowel cancer, CVD and diabetes. Fibre can also help with making us for fuller for longer after meals and plays a vital role in making sure our gut is working normally and keeping our gastrointestinal system healthy.

Unfortunately, there is no miracle diet or strategy to help us lose weight and keep it off over the long-term. As fad diets restrict food groups and nutrients they can come with a number of health risks and only offer a short-term solution as they are often unsustainable. Studies also show that at the 2-5 year mark most people regain all their weight. We also do not know if they are safe over the long term or if they can lead to an increase risk of developing diseases.

My Tips for Spotting a Fad Diet

  1. It removes whole foods or food groups and replaces them with supplements, teas or diet pills.

  2. It limits your food choices and advises you not follow a balanced diet with a variety of different foods.

  3. It is recommended by unqualified people, such as celebrities or nutrition “experts” without any valid credentials or qualifications.

  4. It promises you a quick fix.

  5. It promises that you can rapidly lose more than 1 kg of body fat per week.

  6. It offers no evidence to support any of its claims and makes a claim based on a single study or testimonials only, such as from celebrities or “before” and “after” photos.

  7. It sounds too good to be true or makes unrealistic promises. This is usually promising weight loss without having to make any lifestyle changes.

  8. It has really strict rules that focus on weight loss.

  9. It claims that food can change your body chemistry such as pH.

  10. It recommends you only eat foods in a specific combination which is based on your blood group or genetic type.

  11. It claims you need to “detox” your body.

  12. It only focuses on your appearance.

  13. It claims you can live without food or by only having liquid meals.

  14. It tells you that being overweight is due to you have a food allergy or yeast infection.

  15. It is based on a “secret” that doctors haven’t discovered yet.


If you’re FINALLY ready to ditch the diet confusion and find relief from your IBS, CLICK HERE to watch my FREE Masterclass to discover my proven 3 phase roadmap and the surprisingly simple steps you can take to start reclaiming your life from IBS in as little as 2 weeks.



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