What is a Gastric Sleeve?
Gastric sleeve surgery, also known as a sleeve gastrectomy, is a weight loss procedure that reduces the size of the stomach by approximately 75%, leaving a sleeve-shaped stomach. This limits food intake, helping patients lose weight by promoting satiety with smaller portions. Following a strict dietary plan before and after surgery is essential to ensure successful recovery, prevent complications, and achieve long-term weight loss goals.
What to Eat Before Gastric Sleeve Surgery
Before undergoing gastric sleeve surgery, your surgeon and dietitian will advise that you follow a pre-operative diet designed to shrink your liver - this is known as a ‘Liver Shrinkage Diet’ or ‘Liver Reduction Diet’, and is often abbreviated to ‘LRD’. This special diet, usually lasting between 2 and 4 weeks, provides around 1000 calories and no more than 100g of carbohydrates a day. Patients can choose to follow a diet based around high protein, low carb foods, to calorie count, or to have meal-replacement shakes or milk and yoghurts instead. The liver reduction diet reduces surgical risks by making the procedure easier to perform, safer and improves postoperative recovery. You can expect to lose 1 to 2 stone during this diet.
What to Eat 2 Weeks Before Gastric Sleeve Surgery
A low-calorie, low-carbohydrate diet is typically recommended for a minimum of two weeks prior to surgery. This diet aims to reduce liver size by depleting glycogen stores, making the liver less fatty and easier to manipulate during surgery. The liver is moved to one side in order to operate on the stomach during the key-hole procedure.
Example Meal Plan:
- Breakfast: Scrambled eggs with spinach on 1 small piece of wholemeal toast
- Snack: Low-fat Greek yoghurt with berries
- Lunch: Grilled chicken with steamed vegetables and 3 tbsp of cooked rice
- Snack: Handful of almonds
- Dinner: Baked salmon with roasted cauliflower and 2 small new potatoes
- Supper: A pot of sugar free jelly or decaf tea with milk (no sugar)
What to Eat 2-3 Days Before Gastric Sleeve Surgery
In the final days before surgery, you may be asked to transition to a liquid diet to further reduce stomach contents and ease digestion. Note that you will be advised to be ‘nil by mouth’ from midnight the day before your surgery - this means not eating food for around 8 hours prior to the operation. Water is usually allowed up to 2 hours before the procedure.
Example of a Liquid Diet:
- Bone broth (e.g. chicken, beef)
- Protein shakes or protein water
- Meal replacement shakes
- Tea and coffee (limit to 4 cups a day)
- No added sugar squash
What to Eat After Gastric Sleeve Surgery
Post-operative nutrition is broken into several stages to aid healing and help the body adjust to the smaller stomach capacity.
Stage 1 – Clear Fluids (Immediate Post-Operative Diet)
Immediately after surgery, you will need to stick to clear fluids to stay hydrated and allow your digestive system to heal.
Allowed Fluids:
- Water
- Diluted squash
- Herbal or fruit tea
- Clear broth
- Apple juice
Avoid caffeinated, carbonated, and sugary beverages. Drink according to your surgeon’s instructions, for example 30-50ml an hour, building up to 100ml an hour.
Sample Diet Plan:
- Morning: 200ml water or herbal tea
- Mid-morning: 100ml clear broth
- Afternoon: 200ml diluted squash
- Evening: 50ml apple juice with 150ml water
Stage 2 – Nutritional Fluids (Weeks 1 & 2)
After tolerating clear fluids, you can progress to more nutritious liquids, building up to around 200ml an hour once home, and a total of 1.5 to 2.5 litres of fluid. Remember that ¾ of what you drink should be nutritious, with the aim of having 60-80g of protein a day by day 3 to 4.
Fluids should be thin enough to pass through a straw, but don’t use a straw as this encourages swallowing air, which could lead to bloating and discomfort.
Recommended Drinks:
- Skimmed or semi-skimmed milk (or unsweetened soya milk)
- Smooth soups (strained to remove lumps) e.g. chicken or lentil or tomato with skimmed milk powder
- Bone broth
- Protein shakes
- Protein water
- Meal replacement shakes
- Unsweetened fruit juices (in moderation) diluted with water
- Homemade smoothies with fruit, milk and protein powder (blend until smooth)
Sample Diet Plan:
- Breakfast: Protein shake
- Mid-morning: Protein water
- Lunch: Bone broth
- Snack: Milky decaf coffee
- Dinner: Protein-enriched smoothie
Stage 3 – Pureed Foods (Weeks 3 & 4)
Once you can tolerate liquids, you can introduce soft pureed foods. Blend or mash your food well so that it’s lump free and of a yoghurt like texture. You could try soggy Weetabix or Ready Brek, mashed tinned fruit, blended fish in sauce, mashed potato with cream cheese, humous, blended bolognese or fish stew with pureed vegetables, as well as thicker soups.
Try to have three to four meals a day of one to two tablespoons per meal and gradually increase this up to a maximum of four tablespoons. Make sure you include protein in each meal. Include one to two pints of milk a day (or 2 protein drinks) which can be used to blend foods or drunk between meals.
Do not drink at mealtimes (sips are allowed), instead leave a 30 minute gap between drinks and meals to avoid discomfort, bloating, nausea, vomiting and dumping syndrome.
Example Foods:
- Plain yoghurt
- Blended Weetabix or porridge
- Dhal
- Blended or mashed fruits (no skin)
- Plus 2 protein drinks a day
Sample Diet Plan:
- Breakfast: Fine porridge or weetabix with mashed banana
- Mid Morning: Protein water
- Lunch: Mashed sweet potato with fish blended with a white sauce and mushy peas
- Mid Afternoon: Protein shake
- Dinner: Blended lentil and vegetable soup
Stage 4 – Soft & Crispy Foods (Weeks 5 & 6)
At this stage, introduce soft foods for a week, and then crispy foods the following week, while continuing to avoid tough or fibrous textures i.e. tough meats such as steak and stringy vegetables such as celery.
Start by adding soft foods and lumps to your diet. Ideas include minced or wafer thin meats, fish, cauliflower cheese, cottage cheese, tinned or soft fruit, scrambled eggs, cooked vegetables, rice and pasta (not overcooked). Aim for three small meals per day, and one protein drink to help you to reach the 60-80g of protein that you need a day.
If you can tolerate a soft diet, you can then introduce crispy foods such as melba toast or breadsticks with low fat cream cheese or hummus.
Remember to chew each 20p mouthful of food at least 20 times before swallowing.
Example Foods:
- Scrambled eggs
- Soft fruits (bananas, canned peaches)
- Cottage cheese
- Melba toast with hummus or cream cheese (from week 6, chewed well)
- Plus 1 protein drink a day
Sample Diet Plan:
- Breakfast: Scrambled eggs with chopped tomato
- Mid Morning: Protein water
- Lunch: Bolognese with lean mince and vegetables
- Mid Afternoon: Plain yoghurt and berries
- Dinner: Soft fish with steamed vegetables with 1-2 small egg-sized potatoes
Stage 5 – Normal Texture Diet (Weeks 7 & 8)
After around 7 to 8 weeks, you should be able to resume a normal-textured, fairly solid, and healthy balanced diet. Your gastric sleeve will allow you to eat almost any type or texture of food, provided you chew the food well before swallowing, although some people do struggle with some textures e.g. white doughy bread, chewy meats, and sugary foods - as the latter trigger dumping syndrome. You should aim for three well balanced meals each day, topping up with a protein drink if needed e.g. on the days you do a workout.
Your calorie intake should be above 1000 kcal per-day two months post op, although you do not need to calorie count every day.
Sample Diet Plan:
- Breakfast: Porridge with banana and seeds
- Mid Morning: Plain yoghurt and berries or cheese and crackers
- Lunch: Grilled chicken and roasted vegetable quinoa salad
- Mid Afternoon: Handful of nuts with dried fruit
- Dinner: Stir-fried tofu with vegetables and basmati rice
Potential Risks After Gastric Sleeve Surgery
Some post-surgery dietary issues may include:
- Nausea or Vomiting - caused by eating too quickly or too much at one time
- Constipation - due to reduced fibre and fluid intake
- Dumping syndrome - rapid gastric emptying, causing nausea and dizziness, which is triggered by eating and drinking at the same time or by consuming rapidly absorbed carbohydrates such as sweets or chocolate.
Long-Term Diet After Gastric Sleeve Surgery
Maintaining a healthy diet long-term ensures continued weight loss and prevents complications.
Foods and Drinks to Avoid:
- Carbonated drinks - if you do order a fizzy drink, ask for it over ice and try to knock out as much fizz as you can with a straw or spoon (NB do not use the straw to drink out of as it encourages swallowing air).
- Fried foods - limit as much as possible, due to their high calorie density
- Ultra-processed snacks (crisps, biscuits) - focus on prioritising nutrient dense whole foods where possible
- High-sugar foods (cakes, sweets) - small amounts, infrequently, may be tolerated.
Nutritional Requirements
- Due to a reduced stomach capacity, supplements may be necessary, these often include:
- A daily multivitamin - usually taken on a full stomach
- Calcium with vitamin D - once or twice a day
- An iron supplement - leave a 2 hour gap between calcium and vitamin D tablets
- Vitamin B12 injections every 3 months
Portion Control
Post-surgery meals should be small but nutrient-dense. Eat three small meals a day with no more than five hours between meals. Bariatric portion plates can be bought online - they are around a tea-plate in size and encourage users to fill half the plate with protein, just over ¼ with vegetables and just under ¼ with carbohydrates - to be eaten in that order.
Key Points to Remember After Gastric Sleeve Surgery
- Eat three small healthy and balanced, protein rich meals a day with no more than five hours between meals, even if you don’t feel hungry.
- Aim for at least 60g of protein a day.
- If you feel hungry between meals, take a drink first to make sure you’re not confusing hunger with thirst. If you’re still hungry, have a small snack such as a piece of fruit or yoghurt.
- Eat slowly by putting a small amount of food in your mouth at a time and chewing at least 20 times.
- Don’t eat until you are ‘full’. Overeating will stretch your stomach pouch and may make you vomit.
- Don’t eat and drink at the same time. Wait at least 30 minutes after a meal before you have a drink.
- Make sure you have at least 1.5 - 2 litres of fluid a day.
- Avoid all fizzy and sugary drinks.
- Take your vitamins daily (including a multivitamin, calcium with vitamin D and iron) in addition to B12 injections every 3 months
- Ensure you get your yearly bloods done - as per BOMSS guidance.
For further information visit our gastric sleeve page.
Weight Loss Surgery with Ramsay Health Care
Ramsay Health Care is a leading provider of weight loss surgery in the UK. Ramsay offers weight loss procedures performed by experienced bariatric surgeons who are highly qualified and have undergone intensive specialist training.
At Ramsay Health Care your weight loss surgeon will work in a multidisciplinary team who liaise with each other to provide the best plan of action for you. They include a dietitian who will meet with you and produce a bespoke eating plan, and specialist trained nurses who will be by your side during your journey to offer support and guidance to ensure that you achieve your goals.
Contact us for more details.
Gastric Sleeve Diet FAQs
Can you ever eat normally after a gastric sleeve?
Yes, but portion sizes will remain smaller, and certain foods may cause discomfort. Drinks should be kept to 30 minutes either side of meals.
How much weight will I lose 3 months after gastric sleeve?
Most patients lose around 15-20% of their starting body weight in the first three months, with a target of 30% by 9 months, and 75% excess body weight lost by 1-2 years post op.
When do you start feeling hungry after gastric sleeve?
Hunger signals may return after several weeks to months, but smaller portions will satisfy you. Ask to speak with your dietitian, or our in-house psychologist, if you would like additional support.
What is the fastest way to recover from gastric sleeve?
- Follow your diet progression carefully
- Consume at least 60g of protein a day
- Take the recommended vitamins
- Stay hydrated (between meals)
- Avoid overeating as well as sugary foods and drinks
Can I eat bread after gastric sleeve?
White bread is not recommended initially; whole grain bread should be reintroduced slowly, and it should be thinly cut or toasted initially (during the soft and then crispy texture weeks).
For more information, visit Ramsay Health Care’s Weight Loss Surgery Blog to read:
Weight loss results from having a gastric sleeve | Weight Loss Surgery | Ramsay Health Care UK
Before and After Gastric Sleeve Surgery | Ramsay Health Care
Weight Loss Surgery - The Benefits and Risks
Weight Loss Surgery | Bariatric Surgery | Ramsay Health Care UK