What is SIBO-Safe?

The SIBO diet is a combination of 2 or more diets, all of which consist of easily fermentable/digestible foods, aimed to pass quickly through the small intestine and thus reduce the food source to “starve” the bacterial overgrowth. It is essential to combine this diet with Intermittent Fasting and prokinetics as the underlying cause of SIBO is typically impaired gastric peristalsis/gut motility(1). 

The impact our diet has on our intestinal bacterial populations is significant. What we choose to consume also feeds our gut microbiota ecosystem, which in turn, influences our mental and physical health. Indeed, our gut microbiome, which have coevolved with us, play such a vital role in nutrient absorption, harvest, storage, and expenditure of energy obtained from the diet and digestion that we would not function without them. “Although incompletely understood, the gut microbiota is implicated in a variety of host functions involving intestinal development and function, micronutrient synthesis, and drug metabolism.”(2) The role which small intestinal microbiota plays it is still unclear but they are known to be essential in regulating the processes involved in digestion and absorption(3).

Before implementing the diet it is vital that these 2 states are understood; feeding and fasting. Normal GI motility involves a complex, tightly coordinated series of events designed to move material through the GI tract. During periods of fasting (the interdigestive period), the Enteric Nervous System-programmed migrating motor complex (MMC) is generated - a repetitive “wave” created from the contractile behavior of the SI musculature approximately every 90-120 minutes, sweeping residual debris through all 12 feet of the upper GI tract. This “housekeeper wave”, regulated by the gastroprokinetic hormone motllin, is responsible for cleaning the small bowel between meals and preparing and cleansing the GI for the next meal. The MMC/peristalsis contractions occur when digestion and absorption is complete and the intestine is empty of nutrients 2–3 h after a meal. 

“A normal motility small bowel pattern and preserved migrating motor complex (MMC) is necessary to provide a balanced transit time for food to pass through the small intestine. While the transit time must be long enough to allow for the absorption of nutrients, a prolonged transit time can result in stasis of the food precipitating problems such as small intestinal bacterial overgrowth (SIBO), chronic inflammation, mechanical and visceral pain, and constipation.”(4)

If the gut is not allowed to rest sufficiently and we overfeed or feed too frequently (you should leave at least 4-5 hours between each meal), MMC dysfunction is likely to occur and consequently, SIBO/gut dysbiosis(5), (6). 

Knowing When To Eat

Dr Michael Mosley discusses on his site The Fast 800, how 21st century western populations’ eating-habits have been attributed to diseases which did not exist until very recently, such as the increasingly common 80+ different types of autoimmune diseases. He includes a lot of useful advice on different time restricted feeding schedules as well as on diet, recommending also a lower carb, higher fat, Mediterranean style of eating. The Mediterranean diet has also been linked to health and longevity and similar to our diet, it focuses on veg and fish - tonnes of fibre and a limited meat-protein intake.

Your individual case of SIBO and the condition of your gut will determine which Intermittent Fasting schedule is most appropriate for you. For instance, our SIBO was chronic and our gut motility impaired to such a degree that we had to intermittent fast daily, undertake regular short water fasts weekly (40 hours+) as well as a 7+ day fast monthly. We made sure we refed sufficiently and sensibly in between fasts - super important!

Listening to your body is crucial. However, this becomes tricky in those with intestinal dysmotility, as the whole gastrointestinal process is faulty. This includes hunger signaling which is linked to gastric motility, the MMC and motilin and communicated via the Enteric Nervous System, or “second brain”, which governs the physiological function of the gastrointestinal tract(6). 

“The enteric nervous system is connected to the central nervous system (the brain and spinal cord) via the gut-brain axis. This is not a physical axis, but rather a term to collectively describe the interrelationship of the intestines and the brain.”(7)

Thus the hormonal, chemical and neuronal signalling pathways from the “second brain” which tell us when we are hungry and should eat are dysfunctional and untrustworthy. Added to this, we know that our gut microbiome controls our food choices, appetite and feeding behaviours. “Your body normally secretes hormones like ghrelin (to stimulate your appetite) and peptide YY (to signal that you are full). Many gut bacteria are able to manufacture small peptides that mimic these hormones.”(7) As our microbes interfere with and dominate our appetites directly, it’s important to recognise that hunger you feel is their hunger and they are always hungry for more food! In fact, they feel down right greedy at times! Try to not allow yourself to be controlled by their needs and instead, recognise and your own body’s needs - ensure you stick to your healing groove and the super safe SIBO diet. Do what is right by you and your gut, not those pesky bugs! Once you’ve chosen your new routine, your digestive system will adapt quickly to the feed-fast windows and hunger should diminish. 

The established SIBO diet(8) is a combination of multiple diets - as if being on one diet is not restrictive enough! - the Specific Carbohydrate Diet (SCD), the Gut and Psychology Syndrome Diet (Gaps Diet) specifically for gut repair, the Low FODMAP Diet (LFD) or a combination of these diets such as SIBO Specific Food Guide (SCD + LFD). There is also the Elemental Diet which focuses on liquid consumption instead of solid food consumption, aiming to unburden the gastrointestinal tract and fix gut motility function.

• The Low FODMAP Diet (LFD). The most comprehensive list to date is found via the Monash University FODMAP site. Their diet app can also be downloaded on your phone - very handy when in the supermarket. As it’s a long list, it can take time to remember the safe and unsafe foods. But remember that not all are SIBO-safe. Adhere by the SCD diet below also.
• The Specific Carbohydrate Diet (SCD). The official list can be found via the Breaking the Vicious Cycle site, which is a great introduction. A very useful and more in depth information source all about this diet can be found here.
• The GAPS (Gut and Psychology Syndrome) Diet. The clue is in the name - it was originally designed as a natural treatment for people with conditions that affect the brain, such as autism, and as such targets gut health. This elimination diet is similar to those above, focussing on the SIBO-safe food and promoting gut motility and repair.
• The Elemental Diet (ED). We chose to intermittently water fast instead of going on this diet, as it has significantly more benefits for health and gut repair. Whether you should choose this diet or not will depend on the condition of your gut. In this interview, digestive health expert Lela Altman, ND, LAc, explains how the elemental diet allows the gut to rest and repair. She offers practical information for patients and practitioners about how to choose an elemental diet or how to make your own. 
• The AutoImmune Protocol (AIP). Whether or not you need to follow this diet depends on whether you have leaky gut syndrome or not. Those with chronic SIBO are more likely to have a “leaky gut”. This diet aims to reduce inflammation in the gut, so should not be ignored by those with chronic gut conditions. More information can be found here but note that it includes “unsafe” foods for SIBO-sufferers. Many of our recipes are AIP-friendly, excluding nuts, grains, seeds (except some spices) and many other potential nasties.

***Remember that no form of sugar, whether it be natural or processed, is allowed on this diet. The natural sweetener Stevia is the safest sugar alternative and licorice tea can be used also but in very small amounts).

***Eating out and eating any food you did not make/prepare yourself poses a risk and can hinder your healing. Although a huge challenge socially and energy-wise, we recommend you prepare all of your meals yourself so that you have complete control over the ingredients and portion sizes. It’s better to be on the safe side.