Diet

Anyone with APS is advised to eat a healthy balanced diet with plenty of good carbohydrates, protein, low-fat dairy products and lots of fruit and vegetables. Maintaining a healthy weight is important both in terms of reducing cardiovascular risks such as heart disease, and easing pressure on your bones and joints.

If you are taking warfarin you should try to keep your vitamin K intake as consistent as possible. Warfarin works by interfering with how the liver uses the vitamin K and is affected by the amount of vitamin K in your diet. If your diet is reasonably consistent, then the level of vitamin K should stay the same and not affect your INR and warfarin dosage.

If your diet already contains foods rich in vitamin K, there is no need to change it or restrict the types of food you are eating; however, if you binge on foods rich in vitamin K, it will make the blood more likely to clot and will lower your INR. Green leafy vegetables are among the foods high in vitamin K, but you should not avoid these as they are vital for a healthy balanced diet and can actually help you absorb your warfarin. Instead, you should try and maintain the same daily intake.

Recent research indicates that patients who have unstable INR control tend to have a poorer dietary intake of Vitamin K than patients with a stable INR and, therefore, it may be beneficial to provide such patients with supplementary Vitamin K to their diets to stabilise their INRs. However, more research is needed until this is confirmed.

If you decide to change your diet, such as increasing your vegetable intake, you should discuss this with your doctor or anticoagulation clinic as they may need to monitor your INR more frequently and you may need to increase your warfarin dosage. Likewise, if your diet begins to include more foods that are low in vitamin K, your warfarin dose may need to be decreased.

As well as monitoring the vitamin K content in foods, people with APS who are taking warfarin should also be aware that some herbs and spices are natural anticoagulants so it is best not to binge on these and only consume them in moderation otherwise your INR could increase. There are also many popular natural herbal or health remedies warfarin that may potentially affect so you should discuss this with your doctor or anticoagulation clinic before introducing them into your diet.

You should also try to keep your alcohol intake as regular as possible if you are taking warfarin due to the complex interaction between alcohol and warfarin. Alcohol affects warfarin on two fronts—by acting as a mild anticoagulant and affecting the metabolism of the liver which is important for metabolising warfarin.

As a rule of thumb, two or three drinks per day – such as a glass of wine or a pint of beer are unlikely to affect your warfarin levels. However, intermittent binge drinking leads to an increase in the INR level due to warfarin being metabolised more slowly, while chronic heavy alcohol intake results in a lower INR level because the alcohol increases the metabolism of warfarin.

Alcohol is not the only drink which can have a detrimental effect to people taking warfarin. It was discovered that drinking extremely large quantities of cranberry juice can act to intensify the potency of warfarin and, therefore, increases the risk of bleeding. This is thought to be due to the chemicals called flavonoids which are contained in cranberry juice. Although cranberry juice can provide a cheap means of preventing urinary tract infections because the flavonoids appear to prevent bacteria from sticking to the walls of the bladder, they can also inhibit the action of substances which the body uses to break down warfarin which, in turn, can cause a haemorrhage.