Nutritional Guidelines for FCS

People with FCS are recommended to eat no more than 10 to 15 g of fat per day OR restrict total dietary fat to < 10% to 15% of total daily calorific intake. Fat intake should be spaced throughout the day.

Eating a very low fat diet can lead to deficiencies in essential fatty acids and fat soluble vitamins so regular monitoring is advised to ensure that they have a suitable levels of essential fatty acids and the vitamins A, D, E, K with supplementation given as needed.

Patients are recommended to limit their intake of added sugars and advised to eat complex carbohydrates such as pulses and brown bread.  Complex carbohydrates release their sugars more slowly and allow the body to process them more efficiently. Excess sugar in the blood is turned into triglycerides, exacerbating the risk of abdominal pain and other symptoms.

Over the long term a diet high in sugar can lead to the onset of diabetes due to insulin resistance where the insulin becomes less effective.  This in turn leads to high blood sugar levels which are turned into triglycerides exacerbating the risk of developing the symptoms of FCS.


Complex carbohydrates digest slowly managing blood sugar levels

What fat can I eat?

The lack of functioning lipoprotein lipase means that people with FCS are unable to eat any type of fat. This is all fats whether animal fat or fat from vegetables, nuts and seeds.

There is no such thing as a 'good fat' for patients.  The restrictions include fat from dairy, egg yolks, fruits like avocado, olives and coconut, nuts, seeds, legumes such as soya and chickpeas, as well as fat from animals. So, saturated fat, unsaturated fat and trans-fats.

Excessive fat in the diet will lead to an increase of triglyceride levels leading to a build up of chylomicrons, responsible for causing abdominal pain and pancreatitis.

There are many ways to cook delicious food without fat.  Griddle pans without added fat are an easy way to cook very low fat meats effectively.

MCT Oil (medium chain triglyceride)

People with FCS can, however, use a medically prescribed, specially-treated oil called MCT oil (Medium Chain Triglyceride).  This is an oil that has been fractionated so that it follows a different pathway through digestion, bypassing the gut and being absorbed in the liver, meaning that the lipoprotein lipase enzyme is not required in the process. 

MCT oil is available in health shops and online but should be bought with extreme caution. There are many brands of MCT oil available which are not suitable for people with FCS.  It is important to find a ‘medical grade’ product.    The prescribed brand in the UK is shown here. 

MCT can be difficult to use as it burns easily but many people with FCS have found it a useful addition to their diet. For some it can leave an unpleasant aftertaste and cause bloating, so it is recommended to introduce it gradually to the diet. 

The key principles to eating FCS healthy

Patients used to eating a diet of less than 15g fat per day have identified many tricks and strategies to help them to maintain the limitations the restrictions impose. The key element is planning. Yes, it does take the spontaneity out of your life, but it keeps you healthy and feeling well and gives you the best chance of fulfilling your commitments and dreams for the future!

Patients used to maintaining the restrictions required by FCS have shared the following approaches to maintaining their regime.

Try to eat a balanced diet over the day, incorporating very low fat protein, carbohydrates and fruit and vegetables.

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Doctors recommend that alcohol should be avoided by people with FCS. This is because alcohol is known to raise triglycerides and excessive alcohol use is the leading cause of pancreatitis.


Smoking is not recommended for anybody but as it is known to raise triglyceride levels among the general population there is an extra reason for people with FCS not to smoke. Doctors recommend that people with FCS do not smoke.


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