How Orlistat Works and Why Diet Matters
No weight loss journey is truly complete without the right diet plan. Even alongside medications, long-term success depends on sustainable lifestyle changes.
One such treatment is Orlistat, which works by blocking about a third of dietary fat absorption. Taken three times daily with meals, Orlistat requires a low-fat diet, not exceeding 15g of fat per meal to minimise side effects and work effectively. This is a clear example where diet can directly affect treatment outcomes.
Read on for a sample diet plan which can help get the most out of your Orlistat treatment.
The Golden Rule: 15g of Fat Per Meal
Health experts advise when taking Orlistat, fat intake should not exceed 15g per meal. Lets break that down:
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Daily fat intake of approximately 40 to 50g - split into 15g per meal - roughly one tablespoon of olive oil
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The 30% rule - no more than 30% of the day's calories should come from fat. Based on a 1,400 to 1,500 calorie diet - this aligns with 40-50g fat daily.
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Check the labels - foods showing no more than 5g fat per 100mg are generally defined as ‘low-fat’
7-Day Orlistat Meal Plan
The following Orlistat meal plan provides 7 days of low-fat meals. Each meal contains under 15g fat with a daily calorie target of approximately 1,400 to 1,500 kcal. On average:
- 1 gram of fat provides 9 calories
- 1 gram of carbohydrates contains 4 calories
- 1 gram of protein contains 4 calories
Using this information along with nutritional information on food packets can help formulate a diet plan such as the sample plan below:
Day 1
| Meal | Food Choice | Fat (g) | Calories |
|---|---|---|---|
| Breakfast | 40g porridge with 200ml skimmed milk and a handful of blueberries | 3g | 280 kcal |
| Lunch | Tuna salad wholemeal wrap (tuna in brine) with 1 tsp light mayo and spinach | 5g | 320 kcal |
| Dinner | Grilled skinless chicken breast with 150g boiled new potatoes and steamed broccoli | 4g | 410 kcal |
| Snack | 1 apple and a low-fat probiotic yoghurt | 1g | 140 kcal |
| TOTAL | 13g | 1,150 kcal |
Day 2
| Meal | Food Choice | Fat (g) | Calories |
|---|---|---|---|
| Breakfast | 2 slices wholemeal toast with 2 tbsp low-fat cottage cheese and sliced tomatoes | 4g | 290 kcal |
| Lunch | Roasted tomato and basil soup with a small wholemeal roll | 5g | 310 kcal |
| Dinner | Turkey mince bolognese (lean) with 60g wholewheat spaghetti | 7g | 480 kcal |
| Snack | 2 large rice cakes with a thin layer of honey | 1g | 120 kcal |
| TOTAL | 17g | 1,200 kcal |
Day 3
| Meal | Food Choice | Fat (g) | Calories |
|---|---|---|---|
| Breakfast | 1 poached egg on 1 slice of unbuttered sourdough toast | 6g | 240 kcal |
| Lunch | Prawn stir-fry with ginger, garlic, soy sauce and 150g rice noodles | 3g | 340 kcal |
| Dinner | Baked cod fillet with lemon & parsley, served with mashed peas and carrots | 4g | 390 kcal |
| Snack | 100g fat-free Greek yoghurt with honey | 0g | 110 kcal |
| TOTAL | 13g | 1,080 kcal |
Day 4
| Meal | Food Choice | Fat (g) | Calories |
|---|---|---|---|
| Breakfast | 45g Bran flakes with semi-skimmed milk and a sliced banana | 4g | 310 kcal |
| Lunch | Sliced turkey breast in pitta bread with grated carrot, cucumber and 1tsp mustard | 3g | 300 kcal |
| Dinner | Sweet potato and chickpea curry with 50g brown rice | 6g | 450 kcal |
| Snack | Small bag of plain popcorn | 2g | 90 kcal |
| TOTAL | 15g | 1,150 kcal |
Day 5
| Meal | Food Choice | Fat (g) | Calories |
|---|---|---|---|
| Breakfast | Smoothie: 1 scoop whey protein, 100g frozen berries with water or skimmed milk | 2g | 250 kcal |
| Lunch | Jacket potato with baked beans and large salad (no dressing) | 1g | 380 kcal |
| Dinner | Grilled lean beef steak, with a baked sweet potato and asparagus | 9g | 420 kcal |
| Snack | 4 wholegrain crackers with low-fat light soft cheese | 4g | 180 kcal |
| TOTAL | 16g | 1,230 kcal |
Day 6
| Meal | Food Choice | Fat (g) | Calories |
|---|---|---|---|
| Breakfast | Mushroom (2-egg) omelette cooked with low-fat cooking spray | 10g | 260 kcal |
| Lunch | Couscous salad with grilled peppers, chickpeas, parsley and lemon juice | 4g | 350 kcal |
| Dinner | 100g grilled Salmon fillet with steamed kale and 2-3 new potatoes | 13g | 440 kcal |
| Snack | 2 satsumas or a peach | 0g | 60 kcal |
| TOTAL | 27g | 1,110 kcal |
Day 7
| Meal | Food Choice | Fat (g) | Calories |
|---|---|---|---|
| Breakfast | Low sugar granola with fat-free natural yoghurt | 6g | 320 kcal |
| Lunch | Lean ham and mustard sandwich on wholemeal bread | 5g | 290 kcal |
| Dinner | Vegetable and lentil stew with a small plain chapatti or wholemeal pitta | 7g | 460 kcal |
| Snack | 1 small square of 70% cocoa dark chocolate | 4g | 80 kcal |
| TOTAL | 22g | 1,150 kcal |
Foods to Avoid on Orlistat
Orlistat users should avoid consuming high-fat foods as these can affect weight loss and cause GI side effects, such as oily stools, flatulence with discharge and liquid stools.
As a guideline, whilst on treatment, it's best to stick to foods containing less than 5g of fat per 100g. These foods are considered low-fat and are less likely to cause side effects.
Common foods high in fat can be swapped for a low-fat alternative, as outlined below:
| Type | Food | Low-fat alternative |
|---|---|---|
| Meat | Visible fat on meat, skin on, fatty meat (sausages, black pudding) | Lean meats or pulses(lentils & beans) |
| Fish | Oily fish, fish canned in oil, fried or battered fish | White fish (cod, plaice) |
| Eggs | Fried eggs, scotch eggs | Egg whites, boiled/poached egg |
| Dairy | Whole milk, cream, ice cream, evaporated milk | Skimmed milk, semi-skimmed milk, low fat oat/soya/coconut milk |
| Cheese | Full fat cheese, cream cheese | Cottage cheese, low fat cheese spreads |
| Fat | Lard, dripping, vegetable oils, butter/margarine, all fried foods | Spray oils, low fat spread |
| Cereals | Pastries, biscuits/cakes, dumplings, fried bread | Wholemeal bread, brown rice, low-fat /sugar breakfast cereals |
| Beverages | Full fat milk drinks, instant malt drinks | Tea/coffee, fruit juices, low fat milk drinks (made with skimmed or semi-skimmed milk) |
Vitamins and Supplements on Orlistat
Orlistat reduces the absorption of fat-soluble vitamins: A, D, E and K. These vitamins need fat to be transported through the body. To avoid a deficiency, patients should take a daily multivitamin containing these vitamins, leaving a 2 hour gap between these and Orlistat
Some medicines also rely on fat to be absorbed. These should also be spaced 2 hours apart from orlistat to avoid absorption issues.
Orlistat Shopping List
To ensure your kitchen is ‘Orlistat-friendly’, save the below Orlistat shopping list which includes low-fat UK supermarket staples:
Fruit and vegetables
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Leafy greens - spinach, kale and rocket
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Berries - blueberries, raspberries, strawberries
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Crunchy vegetables - carrots, peppers, cucumber, broccoli
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Potatoes - new potatoes and sweet potatoes
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Fruits - bananas, apples
Proteins & Dairy
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Skinless chicken breast and extra-lean turkey mince
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White fish - cod, haddock, plaice
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Tinned tuna - in brine (not oil)
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Eggs
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Low fat cottage cheese
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Skimmed or semi-skilled milk
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Fat-free greek or natural yoghurt
Carbohydrates
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Wholemeal bread, wraps or pitta bread
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Oats and bran flakes
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Wholewheat pasta and brown rice
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Low-fat cooking spray
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Tinned tomatoes
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Tinned chickpeas/lentils
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Light mayo
FAQs
What vitamins should you take with orlistat?
Take a daily multivitamin containing vitamins A, D, E, K, and beta-carotene, as orlistat reduces absorption of these fat-soluble vitamins. Take the multivitamin at least two hours apart from your orlistat dose, ideally at bedtime.
Can you drink alcohol on orlistat?
Yes, you can drink alcohol while taking orlistat, but it may slow weight loss and add empty calories. Alcohol does not interact directly with orlistat. Choose low-calorie options and drink in moderation. Be aware that some alcoholic drinks are high in hidden sugars.
What can you not eat on orlistat?
Avoid foods high in fat, including fried foods, full-fat dairy, fatty meats, creamy sauces, and processed snacks like crisps and pastries. Check food labels and choose options with less than 5 grams of fat per 100 grams. High-fat meals cause unpleasant GI side effects while on orlistat.
How much fat can you eat on orlistat?
Each meal should contain no more than 15 grams of fat, with a total daily intake of around 40 to 50 grams. Fat should account for approximately 30% of your daily calories. Distribute your fat intake evenly across three main meals rather than saving it for one.
Do you take orlistat with every meal?
Take orlistat three times a day with each main meal that contains fat. Take it immediately before, during, or up to one hour after eating. If you skip a meal or eat a meal with no fat, you can skip that dose. Do not double up on missed doses.
What happens if you eat too much fat on orlistat?
Eating meals high in fat while taking orlistat will likely cause gastrointestinal side effects including oily stools, flatulence with discharge, and an urgent need to go to the toilet. These effects are temporary and resolve when you return to a low-fat diet.