Getting Started on the Low FODMAP Diet Elimination Phase
Getting started on the low FODMAP diet can be a daunting experience. It is important that before you start you see a doctor and a low FODMAP trained dietitian. Your doctor needs to rule out that your IBS symptoms are not being caused by other serious medical conditions like coeliac (celiac) disease, inflammatory bowel disease, Crohn’s disease, cancer or other medical conditions (BPACnz, 2014; Monash University App, 2014). Once you are on the low FODMAP diet, testing for some of these medical conditions can become more challenging.
It is important that you have the guidance of a registered dietitian who has specialised knowledge in the low FODMAP diet. They will help you navigate the complexity of the diet and make sure that, even on this restrictive diet, you are getting the nutritional requirements that your body needs (Monash University App, 2014; Stanford Hospital, 2014). They will also help you re-challenge and reintroduce high FODMAP food later on in the diet.
This guide is meant to inform you about what to expect, more or less, during the elimination phase and does not replace the support and guidance of trained medical professionals.
What is the Elimination Phase?
Once other possible causes for your IBS symptoms have been ruled out and it has been determined that the low FODMAP diet is right for your body, a low FODMAP trained dietitian will help you start the elimination phase. The goal of the elimination phase is to significantly reduce or completely resolve your IBS symptoms through lowering the total intake of FODMAPs you consume (Muir, 2015; Willams, 2014). The diet does this by removing certain foods that are high in FODMAPs.
FODMAP is an acronym for different carbohydrate groups:
|Fermentable||The process through which gut bacteria degrades undigested carbohydrates to produce gases (hydrogen, methane and carbon dioxide) (Monash University, 2015; Mansueto et al., 2015)|
|Oligo-saccharides||Humans do not have enzymes to break down oligosaccharides so all will be malabsorbed, which is why it is helpful to remove them (Monash University App, 2014; Mansueto et al., 2015).|
|Disaccharides||Lactose found in; milk, soft cheese, yoghurts (Monash University, 2015; Mansueto et al., 2015). Lactose contains two sugar units that are separated by the enzyme called lactase to allow them to be absorbed as single sugar units (Monash University App, 2014; Mansueto et al., 2015). People who are deficient in this enzyme cannot process lactose (Mansueto et al., 2015).|
|Mono-saccharides||Fructose (in excess of glucose) found in honey, apples, high fructose corn syrups and other foods (Monash University, 2015; Mansueto et al., 2015). Approximately 30 to 40% of healthy individuals and people with IBS malabsorb excess fructose (Monash University App, 2014; Mansueto et al., 2015). Glucose can help with the absorption of fructose.|
|(And) Polyols||Sugar polyols (eg. sorbitol, mannitol) found in some fruit and vegetables and used as artificial sweeteners (Monash University, 2015; Mansueto et al., 2015). Polyols are incompletely absorbed across the small intestine, which is why they can cause IBS symptoms (Monash University App, 2014; Mansueto et al., 2015).|
Monash University recommends that you stay on the elimination phase for a 2 to 6 week period (Monash University, 2015). Due to the complexity of the low FODMAP diet a 2 week elimination period is often not long enough, as it can take longer than 2 weeks before you stop accidentally consuming high FODMAP foods.
In reality it is likely that you will stay in the elimination phase of the diet for 6 to 8 weeks before starting the reintroduction phase (Mansueto et al., 2015; Willams, 2014). This time period will give you enough time to understand the complexity of the diet and allow your body to adjust to the low FODMAP foods. Once your symptoms are under control you can then start the reintroduction phase with the guidance of your dietitian.
Where do you find Low FODMAP food lists & serving size information?
Your dietitan will normally provide you with a list of high and low FODMAP foods. Another great way to ensure you are not consuming any high FODMAP foods is to purchase the Monash University Low FODMAP smartphone application. The application contains the latest low FODMAP research, clearly indicates high and low FODMAP foods through a traffic light system, and gives safe serving sizes for each food (Monash University App, 2014). Their system works by rating foods as green (low FODMAP dose), orange (moderate FODMAP dose), and red (high FODMAP dose) (Muir, 2015). Monash University also produces a printed guide, The Monash University Low FODMAP Diet booklet, which is updated yearly.
When undertaking the elimination phase, Monash University researchers recommend that you “avoid the red foods, limit the orange foods, and eat mainly the green rated foods” (Muir, 2015). When consuming the green rated foods it is important that you stick to the serving sizes suggested, otherwise you may consume higher levels of FODMAPs (Muir, 2015). You can eat a number of different green rated foods per meal providing you stick to the serving sizes recommended (Muir, 2015). You will find more information on the importance of serving sizes here. Your dietitian may also suggest additional foods you need to avoid based on your personal food intolerance history.
Where do sneaky FODMAPs hide?
It is also important that you look for hidden FODMAPs in your meals. Many pre-made products and sauces contain high FODMAP ingredients. For example, you need to avoid products made with high FODMAP fruits/vegetables (particularly onions and garlic), high fructose corn syrup (HFCS), inulin, honey, and wheat (Monash University App, 2014; Stanford Hospital, 2014). If the high FODMAP ingredient is listed at the end of the ingredient list, then it is likely that the FODMAP level from the high FODMAP ingredient is low, and you may be able to consume small amounts of the product (Monash University App, 2014; Stanford Hospital, 2014). For more information on how to read labels please read our Low FODMAP Guide To Reading Labels.
Is gluten a problem while on the low FODMAP diet?
To reduce oligosaccharides you need to avoid foods that contain moderate to large amounts wheat, barley and rye. While these grains contain gluten, the goal is to limit the oligosaccharides and not the gluten (Monash University, 2015; Stanford Hospital, 2014). This means that consuming small amounts of wheat should not be a problem unless you also have coeliac disease. For more on this topic look here. Additionally, it is important to note that not all gluten free products are low FODMAP. You need to check that the gluten free product does not contain other high FODMAP ingredients.
Are alcohol & caffeine allowed during the elimination phase?
While on the low FODMAP elimination phase it is often recommended that you limit your consumption of alcohol and caffeine (BPACnz, 2014; Monash University App, 2014). While small amounts of caffeine and most alcohols are not high in FODMAPs, they can be gut irritants and stimulate the colon, which can make IBS symptoms worse (BPACnz, 2014; Monash University App, 2014). This means you should test alcohol and caffeine in the reintroduction phase of the low FODMAP diet after talking to your dietitian.
How do you deal with constipation on the low FODMAP diet?
Some people on the low FODMAP diet will experience constipation. This means you may need to increase low FODMAP fibre rich foods (Monash University App, 2014; Stanford Hospital, 2014). Some sources of low FODMAP fibre rich foods are gluten free white bread, gluten free multigrain bread, spelt bread, oats, rice or oat bran, low FODMAP mixed vegetables, potato, kiwifruit, oranges, and raspberries (Monash University App, 2014). For more information on low FODMAP fibre sources check out this article. Additionally, you may need to increase your water intake to reduce constipation and improve general wellbeing (Monash University App, 2014; Stanford Hospital, 2014). If you start to experience constipation after starting the low FODMAP diet consult with your dietitian.
Do you need to keep a food diary?
During the elimination phase you may also discover that some low FODMAP foods are still IBS triggers. Keeping a food diary to track your symptoms can be helpful and allow your dietitian to identify additional trigger foods. For example, we discovered that I cannot tolerate any dairy products. Your dietitian can then advise you on the best way to remove additional trigger foods.
When do you test high FODMAP foods?
Once you have successfully navigated the elimination phase, your low FODMAP trained dietitian will help you start re-introducing high FODMAP foods back into your diet (Monash University, 2015; Willams, 2014; Stanford Hospital, 2014). Follow the link to an article explaining how the reintroduction process works.
Are A Little Bit Yummy’s recipes safe for the elimination phase?
A Little Bit Yummy’s recipes are based on the Monash University Low FODMAP App and safe serving size guidelines, and have been checked by a low FODMAP trained registered dietitian. This means the recipes are safe to use as a resource during the elimination phase.