What does an IBS nutritionist do?

If you’ve never worked with a nutritionist before, you might not be clear on what happens in the sessions, or what to expect in terms of results. To help you work out if this is what you need I’ve tried to answer the most common questions I get.

This post shares what an IBS nutritionist does, day to day, in plain English. I’ll walk you through what happens before, during and after a programme, what tools we use, what kind of advice you can expect, and what makes a good IBS practitioner different from a general one. By the end you’ll be able to understand whether this is the kind of help you’re looking for.

In one sentence

An IBS nutritionist works with you over a period of weeks or months to identify what’s driving your digestive symptoms and puts together a personalised plan that gradually reduces them, using food, gut motility, eating habits, stress, sleep and supplements.

There will be elements of practical work for you between sessions, and then regular catch up calls where we look at progress (or not) and what to focus on next.

The first session: Understanding where you are now

Most first IBS consultations run from 60 to 90 minutes which allows time for you to explain your health history, what you want to focus on, and create a shared understanding of where you are right now.

Here’s what I normally cover in that first session with my clients:

• A full history: When did symptoms start, what’s changed over time, what makes them better and worse, what’s your typical day like in terms of eating, work, sleep and stress.
• A detailed symptom log: Bloating, gas, abdominal pain, frequency, consistency, urgency. A good IBS practitioner has heard all of it many times so you don’t need to be embarrassed about talking about poo.
• Your current diet and eating pattern: What does a normal day’s eating look like and what are your food preferences.
• Test results to date: Stool tests, breath tests, blood work, allergy tests. If you’ve had any, the practitioner will go through them. If you haven’t, they’ll let you know what might be useful.
• Medications and history: it’s important to know what medication you take, how long you’ve been on it, and how it helps. This also ensures no reactions to any supplements.
• Goals: What do you actually want? Less bloating? Eat out without panic? Travel without mapping the loos? Preparing for conceiving a baby? Different priorities lead to different actions for the plan.

By the end of that first session, I’ll have a better idea what’s most likely going on, where you want to focus, and the first one or two things to start changing.

Some people get a bit frustrated that I don’t write out a long plan with week by week actions. But I’ve found this is a waste of time, because things change, life gets in the way. I will give you a short list (2-5 things) to focus on first.

What happens between sessions: your actual work

Most of the work in an IBS programme happens between sessions, when you implement the changes. That’s where you’re trying new foods or styles of eating that I think will help your symptoms.

• Following a tailored eating plan: Many IBS programmes start with a structured period of food experimentation, often using the low FODMAP diet as a diagnostic tool, but tailored to what makes sense for you. The practitioner gives you the framework, the food lists, the meal ideas, and a clear plan for how to move through it.
• Tracking food and symptoms: A short daily note on what you ate, what symptoms you had, when, and how severe. I don’t recommend tracking the whole time, because it gets a bit much doing this for three months. However, it can be useful to take snapshots throughout the three months.
• Implementing meal-timing changes: Adjusting how often you eat, when, and how much. Sometimes the issue isn’t the food choices at all, but more the way you’re eating.
• Small lifestyle changes: Things like nervous system regulation, vagus nerve work, sleep hygiene, and stress management. All can have a real impact on IBS, sometimes more than diet itself.
• Trialling supplements: If supplements are part of the plan, you’ll know exactly what they’re for and how long to take them. Knowing when to stop is also important!

A good practitioner stays in touch between sessions, usually by email or message, so when something doesn’t go to plan you don’t have to wait three weeks to deal with it. I have weekly calls to begin because I like to get to know you and ensure change starts happening quickly.

Follow-up sessions: review, adjust, repeat

After the first session, follow-ups are usually 30 to 60 minutes and happen weekly or fortnightly at the start, spacing out as things improve. In these calls we might:

• Reviewing your food and symptom diary for the week, looking for patterns you might have missed.
• Discussing what’s worked, what hasn’t, what’s been hard.
• Adjusting the plan. Adding things, removing things, troubleshooting.
• Moving you through the next phase, for example from elimination to reintroduction in a low FODMAP plan.

Over a three-month programme the regular conversations give us time to assess how the plan is working out. You can ask me questions, feedback on progress and work through practical issues around meals.

The tools an IBS nutritionist uses

Diet-based tools

• The low FODMAP diet: The most established dietary intervention for IBS, with proper reintroduction. Other diets might include high fibre, dairy free, gluten free, or low histamine diet.
• Fibre adjustments: Adjusting fibre type and amount based on bowel habits, and history of your current diet. Some people need more fibre and more food overall. Others need to adjust the variety or type of fibre they’re eating.
• Strategic reintroduction: Many IBS clients have over-restricted variety and potentially volume of foods over the years. Testing foods and helping you expand your diet is often part of the work I focus on.
• Eating pattern adjustments: When are you eating, how often, portion size, the gap between meals.

Lifestyle and motility tools

• Nervous system regulation: Vagus nerve exercises, breath work, simple body-based techniques to reduce gut sensitivity.
• Sleep hygiene: Quality and consistency of sleep affects gut motility more than people think.
• Movement: Walking, gentle yoga, and posture work all help.
• Migrating motor complex support: Especially relevant for SIBO and slow-motility constipation.

Supplements

• Targeted probiotics: Specific strains for specific situations, not a one-size-fits-all
• Digestive enzymes: If clinically indicated.
• Prokinetics: For specific motility problems.
• Magnesium: For chronic constipation if needed.
• Herbal antimicrobials: For specific cases, with clear rationale.

A good practitioner keeps the supplement list short, and I always try to keep the costs down.

Testing (when justified)

• SIBO breath tests: If SIBO is suspected.
• Comprehensive stool tests: For a deeper look at gut bacteria when relevant.
• Standard blood markers: If undereating, fatigue or anaemia are concerns.

Tests should follow the conversation. If you’re being offered £400 of testing in your first 30 minutes of contact with a practitioner, that’s a flag worth thinking about.

What an IBS nutritionist doesn’t do

Worth being clear about, especially if you’re new to this. There are several things a nutritionist (including a registered nutritional therapist like me) doesn’t do.

• We don’t diagnose medical conditions: If your symptoms could be something else (coeliac disease, inflammatory bowel disease, ovarian or bowel cancer), that’s a job for your GP or a gastroenterologist. A good practitioner will tell you to see your GP first if anything in your history needs investigating.
• We don’t prescribe medication: Painkillers, antispasmodics, laxatives, antibiotics. We don’t prescribe anything pharmaceutical.
• We don’t promise overnight cures: Most IBS cases improve gradually over weeks and months, which is why I don’t see people for one off consultations, it needs repeated sessions over a few months. Chronic conditions have a habit of fluctuating through the week / month so it’s important to look at progress over a longer time period.
• We don’t override eating-disorder care: If you’ve also got an eating disorder, that needs specialist eating-disorder. Some IBS practitioners are trained to spot disordered eating and can refer you appropriately. If you also have issues with your relationship to food or your body it’s a good idea to find someone focussed on eating disorders in the first instance.

What does an IBS nutritionist do differently from a general nutritionist

Nutrition is a wide field. A general nutritionist might work with weight loss, sports performance, menopause, fertility and IBS, all in the same week. An IBS specialist sees gut health clients and keeps their focus on digestion. This means:

• It’s easier to spot patterns – After hundreds of cases, an IBS specialist can spot what’s going on much faster.
• Up-to-date on research – There are 1000s of gut health studies published every year on the gut microbiome, the low FODMAP diet, SIBO, reflux etc. so it’s important to stay up to date.
• Familiarity with related cases – Even if it’s not classic IBS, an IBS nutritionist will be familiar with adjoining conditions such as bile acid diarrhoea, mast cell issues, coeliac disease etc.
• Keeps focus broader than just food – A specialist has experience to know when IBS treatment needs to focus on relationship with food, exercise or stress management, alongside diet changes.

If you’ve been DIY-ing your IBS for a while, you don’t need a generalist nutritionist. You need someone whose job it is to talk about the ins and outs of digestion all day long!

Common questions

How long does an IBS programme usually take?

Three months is the most common length. That’s enough time for a structured elimination, a proper reintroduction and to start consolidating the changes. If your symptoms aren’t resolved within my 3 month Gut Reset then you’ll have a plan for what to do at the end of the programme – what to continue, when to change etc.

Do I have to give up loads of foods?

Sometimes, but with my clients it’s often the opposite. A lot of clients arrive having cut out more than they need to, and I help decide which foods could be retested and how. My aim is always to get you on a broader diet, with fewer food rules.

Will I be told to take a load of supplements?

Not by a good practitioner. Supplements are used selectively, with clear reasons and end dates are given as part of the protocol.

What if I’m vegan, gluten-free, or have other dietary needs?

Sometimes ethical choices, food preferences, cultural influences and other medical conditions can create additional elements of the diet we need to think about, but there is always a way through if we work together. I’ve got experience working with many different diets and food needs.

Can I work with an IBS nutritionist online?

Yes. Most specialist IBS nutritionists work entirely online now, which is good news because it means you can choose based on specialism, personality fit and approach rather than just whether you live nearby.

If this sounds like the support you’ve been looking for

An IBS nutritionist I’m here to look at your specific situation, build a clear plan, and walk alongside you for a few months while you put it into practice. There isn’t a magic protocol I can give out after one call and off you go. Although it’s quite time intensive for both of us working in the 3 month Gut Reset can make huge changes.

If you’d like to see whether working together would be a fit for you, I offer a free 30-minute discovery call. I’ll ask about your symptoms, what you’ve tried, and what you’d like to be different. If I can help, I’ll explain how. If I’m not the right fit, I’ll point you somewhere that might be.

IBS Nutritionist

Hi, I’m Anna Mapson, registered Nutritional Therapist.

I help people with IBS and SIBO get control of unpredictable gut symptoms to find long term relief from painful and embarrassing IBS without restrictive dieting.

I can help you to:

• understand your digestion better, so you recognise your triggers
• eat a well balanced diet, with tasty meals that are simple to prepare
• reintroduce your trigger foods so you can get back to enjoying food again

Find more about my 3 month 1:1 Gut Reset programme.