Dietary Management of Functional Dyspepsia, Nausea and Vomiting disorders including Gastroparesis

This page contains a lot of information, take your time to read.

But to get you started here is an overview of the key dietary advice in an image, and below a brief explanation of the key points.

These tips can help manage bloating, fullness, pain, nausea or vomiting. Try them for 4–12 weeks and adjust to your preferences.

Eat Mindfully: Take your time to eat (do not eat fast), chew properly, and sit upright for 1–2 hours after meals (a light walk is also helpful). Avoid lying down for 3–4 hours. Stop eating before you feel too full.

Regular Meals & Adjusting Portion Sizes: Have 3 meals per day. Avoid skipping meals or long gaps. Smaller meals with extra nourishing snacks like yoghurt, soup or smoothies snacks may be needed.

Manage Fluids: Sip drinks through the day but limit to half a glass (~100 ml) with meals. Be aware fizzy drinks, using straws and drinking too fast can all cause symptoms.

Softer Food Textures: Aim for at least one-third of your meals to be soft or liquid (soups, casseroles, smoothies, mashed or slow-cooked foods, soft fruits and vegetables, minced or slow-cooked meats). If symptoms are worse, make two-thirds of your meals soft or liquid.

Fat Intake: Avoid solid high-fat foods (see table 1). Check food labels – 'High fat' = over 17.5 g fat per 100 g. Softer/liquid fats (smoothies, ice cream) are often better tolerated.

Fibre Intake: Soften high-fibre foods (see table 2). Check food labels – 'High fibre' = over 6 g fibre per 100 g.

Gut Irritants: Limit alcohol (≤14 units/week), caffeine (≤3 cups/day) and chilli (use mild or avoid for 4–12 weeks).

Be Flexible: Symptoms can change from day to day. Adjust your diet: Mild days: mostly normal meals with some softer foods. Bad days: smaller meals, more soft or liquid foods, and nourishing drinks.

If symptoms don’t improve after 12 weeks, or you are losing weight, please speak with your doctor.

Functional dyspepsia (often called indigestion) and nausea and vomiting disorders including gastroparesis (slow stomach emptying) often share symptoms like early fullness, bloating, nausea, vomiting, pain and upper tummy discomfort.

Details about these conditions are available in the links below.

• Functional dyspepsia by GUTSUK! charity
• Gastroparesis by GUTSUK! charity

Often symptoms are either triggered by eating or symptom severity worsens when eating.

Diet changes can help manage these symptoms and improve your day-to-day comfort. The advice below is divided into two helpful layers:

1. First-line advice: basics that work for most people
2. Second-line advice: how to relax restrictions and reintroduce foods once your symptoms improve

First line advice is ‘generic’ advice that is provided to all patients as the majority will find some benefit from some advice. Use the advice provided here as a template for your diet and adjust the details based on your particular dietary preferences.

How Long Should I Follow This Diet?

Our research at UCLH has found 4 weeks is enough to see a symptom improvement. However, the first line advice can be followed for up to 12 weeks to see if symptoms improve, so keep trying if you do not see any benefit in the first 4 weeks.

Tip 1: Improve How You Eat

Key points:

1. Eat slowly, chew well and take small bites to break food down.
2. Sit upright while eating and stay upright for 1–2 hours afterward. A short walk can help ease digestion. Do not lie down for 3-4 hours after eating.
3. Try not to eat too much at one time, as even one extra mouthful more than your stomach can accommodate at one time can trigger symptoms

Tip 2: Adjust Portion Size & Meal Frequency

Key points:

1. Have a regular meal pattern (i.e. 3 meals per day), avoiding skipping meals or leaving long gaps between meals
2. Try eating smaller and more frequent meals throughout the day, rather than having fewer larger meals
3. Attempt to eat even if you do not feel hungry
4. If needed take small, nourishing snacks between meals (e.g. a slice of omelette, yoghurt, cereal, or a nourishing drink), especially if you’re at risk of losing weight

Tip 3: Adjust Fluids While Eating

Key points:

1. Avoid drinking more than 100 ml (half a glass) fluid within 30 minutes before or after meals
2. Avoid drinking fast or having large drinks quickly, instead sip fluid throughout the day
3. Reduce unnecessary extra gas by avoiding excessive sucking e.g. using a straw and be wary of fizzy drinks

Tip 4: Adjust Food Texture

Key Points:

• At least one-third of your daily meals should be in soft or liquid textures e.g. fork-mashable / mashed foods, smoothies, casseroles, stews, slow cooked meals, soups or pureed soups.
• If symptoms are more severe, adjust to two-thirds soft/liquid and one-third soft. As your symptoms improve, slowly reintroduce more normal textures
• Typically raw fruits, raw vegetables, salad and stir fried food are less well tolerated. You can still have these foods but need to eat them less often rather than daily.
• Soften textures by cooking fruits (or use frozen fruit), steam, roast or boil vegetables until soft, and choose slow-cooked, minced, or ground meats, poultry, eggs, and fish over large, solid, or fried portions.
• Use food processing techniques, like shown below for oats. Finely ground oats are easier to digest because they move through your stomach faster. Try starting with a very small amount (about 1 tablespoon) and slowly increase your portion to find the size that works best for you.

Tip 5: Fat Intake

Key Points:

• Avoid solid high-fat foods (high fat is anything over 17.5 g fat per 100 g), as fat can slow stomach emptying and worsen symptoms
• Liquid or soft high-fat foods (like smoothies or ice cream) will be better tolerated, as they pass through the stomach faster and cause less sensitivities
• Modify high-fat solid foods by choosing softer forms or smaller portions as displayed in Table 1. You do not need to be on a low fat diet!

Table 1: High fat foods to avoid & modify in your diet

*Check portion guide. In the table where it mentions ‘check portion guide’ this means checking the amount of fat in the product per portion as it may be suitable. For example ¼ of a quiche will not be high fat but is a portion

Nutrition Labels

• You will need to look on nutrition labels for fat content information (>17.5g of fat per 100g)
• Check labels for total fat / 100g (as shown below) and also per portion as some products can be consumed if the portion size recommended is adhered to

Tip 6: Fibre Intake

Key Points:

• Modify the texture of high-fibre foods, rather than avoiding them entirely. You do not need to be on a low fibre diet!
• High-fibre items (>6 g fibre per 100 g) can slow gastric emptying and increase fullness, but texture adaptation helps, see Table 2 for examples.
• Avoid having several high fibre foods in the same meal.

Table 2: High fibre foods to modify texture

Nutrition Labels

• You will need to look on nutrition labels for fibre content information (>6g fibre / 100g)
• Check labels for total fibre / 100g (as shown below) and also per portion as some products can be consumed if you stick to the portion size recommended

General advice for foods that can irritate the gut

• Alcohol, caffeine and chilli are all stimulants to the gut and can increase GI symptoms, however often moderation is the key.

Alcohol:

• Follow ‘Low Risk Drinking Guidelines’ in the UK 14 units per week spread evenly over 3 or more days is advised.

Caffeine:

• It is sensible to restrict all caffeinated drinks e.g. tea / coffee / energy drinks to 3 cups (2 mugs) per day.

Chilli:

• If you regularly consume chilli then avoid foods with large amounts of chilli added and instead opt for ‘mild’ dishes or if using chilli at home use a mild chilli e.g. Jalapeno rather than Scott Bonnet.
• If you only consume chilli occasionally then avoid chilli altogether (for the next 4–12 weeks) as only having it occasionally can increase the risk of experiencing symptoms

Summary of First Line Dietary Advice

• Follow the dietary tips for 4–12 weeks
• Meal habits: chew well, sit upright, eat regular meals with smaller portion sizes if needed more often, and include nourishing snacks
• Fluids: sip throughout the day; limit during mealtime
• Texture: include soft/liquid meals daily; adjust upward as tolerated
• Fat: avoid solid high-fat foods; choose lower-fat or modified textures
• Fibre: modify texture of high-fibre foods rather than avoid; use smaller portions and softer options
• General: Consume sensible amounts of alcohol, caffeine and chilli

Managing Your Gastroduodenal Symptoms: A Flexible Approach to Eating

Your gastroduodenal symptoms can change from day to day, and so can your diet! Think of your eating plan as a flexible tool that you can adjust based on how you're feeling.

This guide will help you understand how to adapt your meals and snacks to better manage your symptoms. The goal is always to maintain good eating habits and listen to your body.

A Flexible Approach to Eating

Here's how to adjust your diet based on your symptoms:

1. Feeling Normal (Green Zone)

• What to do: Eat 3 meals a day. There's no need to avoid specific foods right now.
• Important: Remember not to overeat!

2. Mild Symptoms (Yellow Zone)

• What to do: Aim for 3 meals a day with your usual portion sizes.
• Focus on:
  • Avoiding foods that trigger your symptoms.
  • Avoid high fat solid foods and modify the texture of high fat foods (see table 1).
  • Make high fibre foods softer (see table 2).
  • Ensure at least one-third of your daily meals have a soft or liquid texture (like soup, yogurt, mashed potatoes).

3. Moderate Symptoms (Orange Zone)

• What to do: Have 3 meals a day, but try smaller portion sizes. You might also benefit from 1–2 extra small snacks or nourishing drinks throughout the day.
• Focus on:
  • Avoiding foods that trigger your symptoms.
  • Avoid high fat solid foods and modify the texture of high fat foods (see table 1).
  • Make high fibre foods softer (see table 2).
  • Ensure two-thirds of your daily meals have a soft or liquid texture.

4. Severe Symptoms (Red Zone)

• What to do: Eat 3 small meals a day. You'll likely need 2–3 extra small snacks or nourishing drinks to get enough nutrients.
• Focus on:
  • Ensure two-thirds of your daily meals are in liquid texture (smoothies, broths).
  • The remaining one-third should be soft texture foods.
  • Continue to avoid high fat solid foods and modifying texture of high fat and high fibre foods.

How to Adjust Your Meal Plan with First Line Dietary Tips

The menu example below shows how small changes can make your meals more supportive of your current health needs by adjusting texture and fat/fibre content.

• First please check that you are following the first line dietary advice as strictly as you can. It might be that you need to be very strict with following all the advice contained in this diet sheet.
• Unfortunately dietary therapy will not improve symptoms for everybody and this may be the case for you. In this situation you will need to discuss other treatment options with your doctor. To improve symptoms a combination of treatments including diet, lifestyle, medication and psychological therapies may be needed.
• If your symptoms impact on continued and significant weight loss then you should discuss this with your dietitian and/or doctor as alternative treatments may be required based on nutrition support advice.

End of part 1.

Once symptoms settle, you may be able to relax the dietary advice and try more foods:

Keep What Works

• Continue beneficial habits – chewing well, sitting up, small meals – but if these don’t help, you can ease off

Portions & Mealtimes

• Stick with regular eating patterns, but find what suits you – three meals a day or small meals if that’s easier
• Avoid drinking large amounts with meals; sip fluids throughout the day instead

Stepping Up Food Texture

• Gradually move from liquid → soft → normal textures, keeping at least one-third of your daily intake modified if still needed

Reintroducing High-Fat Foods

• Slowly test tolerance: start with softer and lower-fat versions, and increase texture gradually. For solid high-fat items, use very small portions and build up slowly

Reintroducing High-Fibre Foods

• Try small portions of modified fibre foods (e.g. a slice of bread, tablespoon of lentils), gradually increasing as tolerated

Graded Food Exposure

• For foods that still cause symptoms, consider graded exposure – tiny amounts, gradually increasing over time
• A graded food exposure tip sheet is available on the UCLH website: Graded food exposure tip sheet

• Improving symptoms via 1st line dietary advice can help improve overall food intake and therefore this may achieve some desired gain weight
• If you have become underweight (BMI ≤18.4kg/m2) and/or have lost weight unintentionally and wish to gain weight gain then you may need to include an additional source of calories in your daily diet

Nourishing drinks can replace water

• Milk, juice, smoothies, hot chocolate and any other drinks that contain calories are ‘nourishing drinks’ and may need to replace other low calorie drinks and/or water if weight loss is a concern

Creating Nourishing Drinks

• It can be easier to ‘drink calories’ rather than ‘eat calories’
• Create a ‘nourishing drink’ and include this in addition to your current dietary intake on a daily basis
• You could consume your nourishing drink between meals as a ‘snack’ e.g. 2–3x100ml small drinks during the day or if you can tolerate larger volumes then 1–2 nourishing drinks per day
• Or you could include a nourishing drink as a meal if you previously did not eat a meal

Further Nutrition Support Strategies

• A nourishing plant-based diet

Nutrition support resources are also available from NHS Patient Webinars and the British Dietetic Association (BDA)

• Spotting and treating malnutrition by the BDA 
• NHS Patient Webinar Managing Malnutrition
• Vegan friendly malnutrition advice

Nausea (feeling sick)

• Coping with Nausea (UCLH diet sheet)

Reflux

• NHS Patient Webinar Reflux Diet & Lifestyle Advice

IBS (Irritable Bowel Syndrome)

• NHS Webinar on the first line dietary advice for IBS

Bloating or Distension

• Most advice provided in this booklet will help, but if bloating is a problem, you might benefit from low-FODMAP guidance for bloating (speak to your doctor or dietitian)

The British Dietetic Association provide a useful diet sheet on IBS which includes advice for bloating: Irritable bowel syndrome (IBS) and diet

• Everyone’s experience is different – adjust this advice to suit your symptoms and lifestyle
• If symptoms persist or you’re losing weight unintentionally, further support may be needed, speak to your doctor or dietitian

In Summary

Please contact your doctor or dietitian should you require further information.

Otherwise see below for some trustworthy online resources that you may wish to access and search their websites for relevant information:

• GUTS UK! Charity
• NHS website for England
• ROME Foundation
• NHS Lothian, Dyspepsia Videos
• British Dietetic Association, Food Fact Sheets

Address:

Department of Nutrition and Dietetics,
3rd Floor East,
250 Euston Road,
London,
NW1 2PG

Direct line: 0203 447 9289
Switchboard: 0845 155 5000
Extension: 79289
Fax: 0203 447 9811

Email: uclh.dietitiansdept@nhs.net
Website: www.uclh.nhs.uk