When I was first diagnosed with SIBO, IBS, and Functional Dyspepsia, my first instinct was to take control by changing my diet. I remember thinking that as they were gut problems, it HAD to be caused by what I was eating. If you’re anything like I was, you will probably also feel that radical dietary change is the answer - maybe you've already found some slight symptomatic relief by doing this. But if you're already eating a nutrient-rich diet filled with fruits, vegetables, whole grains, and grass-fed meats, you might be surprised to learn that this probably isn’t necessary.
What dietary changes did I make when I was diagnosed?
I dove headfirst into every diet I could find online, and then tried combining them! I went through the low FODMAP, ketogenic, paleo, carnivore, GAPS, SCD, low histamine, low oxalate, low lectin, vegan diets - you name it, I tried it. Without fail, every single one made my symptoms worse. Instead of finding relief, I spiralled into an extremely restricted diet of only 3 foods (chicken, rice, and carrots) for six months straight (unsurprisingly, my symptoms not only didn’t improve on this regimen, they continued to deteriorate).
There is so much conflicting information to be found online that I became absolutely terrified to eat pretty much anything. One site would tell me to avoid fibre, the next would say cut out fats, and others warned against carbs. It felt like there was no safe option, and I developed quite severe food fear, being scared of increasing numbers of food groups.
Why does diet always seem like the answer?
If you’ve Googled your symptoms, you’ll notice the first thing that pops up is dietary advice. It’s easy to assume that what you eat is the root cause of your symptoms and that changing your diet will fix everything. And in some cases, small dietary adjustments can help. If you tend to eat a lot of sugar and processed foods, it will be impossible to heal your gut without moving to a more whole-foods-based diet.
That said, an over-focus on diet can do more harm than good, leading to stress around food and long-term restrictions that are neither necessary nor helpful.
Does diet actually cure SIBO, IBS and Functional Dyspepsia?
There is no solid evidence that diet alone can cure SIBO, IBS or Functional Dyspepsia [1]. That might be surprising after hearing that cutting out carbs or going ultra-low FODMAP is the answer (and indeed, they can temporarily improve symptoms due to reduced bacterial fermentation). But research shows that even the most restrictive diets don’t eradicate SIBO, instead, the bacteria feast on fats, amino acids and even our gut mucosal barrier [2] [3] [4]
You read that right - if we don’t feed the bacteria, they will actually eat us! On top of that, overly restrictive diets often lead to nutrient deficiencies, especially when you cut out fibre and plant-based foods that are vital for long-term gut health.
SIBO is typically caused by bacterial imbalances in the small intestine rather than too many bacteria, with the overgrowth commonly coming from proteobacteria. These bacteria feed on things like saturated fats and sugars, which is why if your diet is full of junk food, some adjustments might be helpful. But even then, swapping junk for whole, nutrient-dense foods is far more important than trying some extreme dietary approach.
What about the low FODMAP diet?
The low FODMAP diet is the most commonly recommended for people with IBS, and yes, it can offer some short-term relief due to the reduction of fermentation in the gut.
I tried it myself and noticed a reduction in my bloating and pain initially. But the key thing to understand is that the low FODMAP diet is meant to be temporary. Research has shown that staying on it for more than six weeks can actually worsen your symptoms over time - and this is certainly true of what I experienced.
This is because a long-term low FODMAP diet reduces the diversity of your gut bacteria [5], and as SIBO, IBS and Functional Dyspepsia are conditions of dysbiosis, it makes sense that a Low FODMAP diet can worsen these conditions if used for a long period of time.
I you do decide to try low FODMAP, use it as a short-term strategy not a cure. It’s meant to reduce symptoms while you address the root causes of your gut issues. After a few weeks, you’ll need to start reintroducing foods to keep your gut and microbiome healthy.
Can I really heal my gut without a major diet overhaul?
The short answer is yes, you can. If your diet is already rich in whole, unprocessed foods, filled with fruits, vegetables, whole grains, and high-quality meats, there’s no need to change it. Sure, it’s always a good idea to cut back on processed junk, but you don’t need to panic about every bite you take.
Eating "well" doesn’t mean going to extremes, and in fact the sweet spot is one of balance. You don’t need to eliminate entire food groups, starve yourself of carbs, or eat like a caveman to heal your gut.
It took me a long time (about 7 years!) to learn this lesson myself. I was convinced that food was the main driver of my symptoms, but in reality, my gut issues had more to do with bacterial imbalances, motility issues, inflammation and other factors like brain-gut axis dysfunction.
How important is adequate nutrition for gut healing?
While it’s clear that diet alone won’t cure you, proper nutrition is essential for overall gut health and healing. Your gut relies on a wide range of nutrients to function optimally, so when you start cutting out food groups or severely restricting your diet you can miss out on key nutrients that your body and gut need to heal.
For example, fibre from fruits, vegetables, and whole grains feeds the ‘good’ bacteria in your gut, helping them thrive and maintain a balanced microbiome. In fact, these ‘good’ bacteria can play a key role by themselves by outcompeting the ‘bad’ bacteria in the gut.
Healthy fats, like those found in avocados, olive oil, and fatty fish, support your gut lining and help reduce inflammation.
Proteins, especially from quality sources like grass-fed meats and legumes, provide the building blocks for tissue repair and immune function.
Additionally, vitamins such as A, C, and D play crucial roles in maintaining gut health. Vitamin A helps maintain the gut lining, vitamin C supports immune function, and vitamin D is vital for regulating inflammation.
When I was on my restricted diet of chicken, rice, and carrots, I was depriving my body of essential nutrients. I wasn’t getting enough fibre, healthy fats, or vitamins and minerals. I could feel the difference - my energy was extremely low throughout the day, my periods stopped, and my gut health got worse because I wasn’t giving my body the tools it needed to heal.
How can I heal my gut without extreme dietary changes?
Healing your gut isn’t just about food. While diet plays a role, the real work lies in addressing the root causes of your symptoms. For many people with IBS, SIBO and Functional Dyspepsia, that includes motility issues, where food doesn’t move through the intestines properly, allowing bacteria to grow. It can also involve low stomach acid, immune system dysfunction, or past antibiotic use.
In my case, once I started focusing on improving motility, dysbiosis, inflammation, stress reduction and nervous system regulation, my gut health improved. Working with a practitioner to address these deeper issues is far more effective than jumping from one restrictive diet to the next.
Can diet ever help?
While diet isn’t the cure, there can still sometimes be a place for temporary diet changes in gut healing. For example, during flare-ups, a temporary low FODMAP diet can help control symptoms and reduce inflammation in the gut. It won’t fix the underlying problem, but it can provide relief while you focus on getting to the root cause. Once your symptoms calm down, it’s essential to reintroduce a wide variety of foods to keep your gut bacteria diverse and healthy.
If you are spending longer than 4 weeks on any kind of restricted diet, please find a qualified practitioner to help you resolve your symptoms AND eat all your favourite foods again.
How do I add foods back into my diet?
If you’ve been cutting out food groups, especially fibre-rich foods, it’s important to start slowly. Begin by adding small amounts of easily digestible fibre, like cooked vegetables or low-fibre fruits. For me, small amounts of stewed apples worked really well. Gradually increase the portion size over time. Once your gut adjusts, you can move on to more fibrous foods like whole grains, legumes, or raw vegetables in small portions.
Pay close attention to how your body responds, and don’t rush the process as your gut needs time to adjust. By slowly increasing your fibre intake, you avoid overwhelming your digestive system all at once.
If your symptoms seem to worsen, don’t panic. Stick with the same amount for 2-3 days, and if the symptoms are still bad, halve the amount of the fibrous food you’ve eaten.
If you are really struggling to reintroduce fibre from food sources, you may want to try PHGG - a low fodmap fibre supplement that is generally tolerated really well by IBS, SIBO and Functional Dyspepsia sufferers. You can start with a tiny dose (literally a sprinkle), and gradually build your way to 5g a day.
I really like this supplement by Invivo. (Note: I have no affiliation to Invivo, this is just the PHGG supplement which I have personally used and which I found beneficial.)
To sum up:
Healing from SIBO, IBS, or Functional Dyspepsia isn’t really about diet. If you’re already eating a balanced diet full of whole, nutrient-dense foods, there’s no need for extreme dietary changes. While it’s tempting to jump on the latest diet trend - whether it’s low FODMAP, Keto, or carnivore - none of these diets are proven to cure SIBO, IBS or Functional Dyspepsia. In fact, long-term restrictive eating can often make things worse.
If your diet consists of processed foods and junk, then what you’re eating could be contributing to your symptoms. Reducing these will help, but it’s more about quality and balance than following any extreme plan. A temporary low FODMAP diet can provide short-term symptom relief, but it shouldn’t be used for more than 4 weeks without reintroducing foods to maintain gut diversity.
Ultimately, addressing the root causes of your gut issues is key to healing. While diet can be a helpful short-term tool, it’s not the answer. You want to be eating ALL your favourite foods and enjoying meals at any restaurant you like, not spending your life batch cooking the same three meals and dreading mealtime.
Healing your gut does NOT mean restriction or miserable mealtimes.
留言