Westminster Refsum’s Diet Principles

The Westminster Refsum’s Diet has been shown to be effective at lowering the amount of phytanic acid in the blood.  The Westminster Refsum’s Diet includes the following principles:

1. Eat regular meals and snacks

This means having breakfast, lunch, evening meal and a bedtime snack. If you have a long break between meals (4 hours or more), have a snack. It is particularly important to eat breakfast, so that you break your overnight fast. It is also important that you do not exercise hard in the morning unless you have eaten breakfast.


Dieting to lose weight is not recommended unless your phytanic acid is in the target range of less than 200µmol/L.  If weight loss is desired and your phytanic acid is low, it is important that you work closely with your dietitian to develop a weight loss plan and regularly monitor your phytanic acid levels.  Any time you lose weight phytanic acid is released from your fat stores; therefore, very slow weight loss would be recommended.

2. Eat carbohydrate rich foods at each meal

The brain needs a regular supply of glucose to function. Without a regular supply of glucose, your body will break down its carbohydrate stores and once it has used those, it will break down your fat stores and release phytanic acid from your body fat. It is very important not to follow a low carbohydrate diet.  Carbohydrates can come from starchy foods (bread, potatoes, rice, pasta, breakfast cereal) and sugary foods (fruit, sweets, fruit juice). 


If you other health conditions such as diabetes, it is important to talk with a Dietitian for specific advice.

3. Avoid foods that contain a lot of phytanic acid

The foods that contain the most phytanic acid are products from:

  • Cows (milk, butter, cheese, cream, products that contain these substances such as cakes or biscuits; ice-cream, beef, burgers, sausages, and meat balls containing beef)

  • Sheep (mutton, lamb, sheep’s cheese, sheep’s milk, sheep’s yoghurt)

  • Oil rich fish (salmon, mackerel, herring, sardines, pilchards, trout, mullet, sea bass, fish oil supplements). 

  • Organic versions of these foods and foods with a very high fat content contain the most phytanic acid e.g. organic butter, organic cheddar, fish oil.

4. Restrict foods that contain a moderate amount of phytanic acid 

Restrict foods that contain a moderate amount of phytanic acid to a portion size not bigger than 80g and do not eat them more than one a week.  The foods that contain a moderate amount of phytanic acid are duck and tinned dressed crab. Nuts should be restricted to less than 30g as a portion and limited to once a week.

5. Limit foods containing phytyl fatty acid esters

Limit foods containing phytyl fatty acid esters to 50g a day. These foods are red and yellow peppers (green peppers do not need to be limited) and rocket salad (arugula).

6. Avoid high intakes of caffeine

Consuming large amounts of caffeine from energy drinks, sports drinks or high intake of coffee is not recommended. If consuming products with caffeine, a moderate caffeine intake is advised. For an adult woman (not intending to become pregnant) this would be 200-350mg a day and for an adult man, 300-450mg a day. 

7. Ensure you are getting your essential fatty acids

Omega 3 and omega 6 are essential fatty acids that the body cannot synthesise and therefore need to be consumed in the diet. Omega 3 and 6 are found in plant oils such as flaxseed (linseed), soybean, and canola oils, and can be a source of essential fatty acids on a low phytanic acid diet. In addition, omega 6 can also be found in chicken, eggs and wholegrain breads. It is important to discuss with your dietitian about ensuring you are getting omega 3 and 6 from your diet.

8. Ensuring adequate carbohydrates when exercising

It is important to fuel your body with carbohydrates prior to exercise. This could include eating a carbohydrate containing meal or snack before exercising. If exercise lasts longer than 45 minutes, you should take a carbohydrate snack during exercise. For example, if you go on a 90-minute walk you should bring a small snack to eat at 45 minutes (e.g. banana, a couple of dates). If you exercise without adequate carbohydrates, your body will start to break down fat and release phytanic acid. If you are starting a new exercise plan or wanting to increase the amount of exercise you do, it is important to talk with your dietitian.

9. Getting enough glucose when unwell

If you are feeling unwell and unable to manage all your usual meals, you will need to consume glucose at regular intervals in order to stop the breakdown of your fat stores and release of phytanic acid into your body. This is called an emergency regime, and an example of one used at Guy’s and St Thomas’ Hospital, London, is included (see Emergency Regimen). This regimen is specific for those who do not have diabetes. If you have diabetes, it is important to contact your medical team and dietitian for specific advice.