Warfarin and diet

Key points about warfarin and diet

What you eat and drink can affect warfarin.
The most important thing is to keep your diet stable.
If you make any changes to your regular diet, tell your doctor, nurse or pharmacist.

Colourful fruit and vegetables on a stall

Warfarin interferes with how your liver uses vitamin K taken from your diet. Some foods are rich in vitamin K and these can affect how warfarin works. As part of a healthy balanced diet, you can continue to eat foods that contain vitamin K in moderate amounts. You don’t need to change your regular eating habits. There is no “correct” amount of vitamin K that you should eat. But, it is important to avoid large changes in the amount of food you eat containing vitamin K.

It is also important to consider the amount of vitamin K you are eating in situations when your diet may change, such as during illness, travel, fad diets, hospitalisation and after surgery. Before making any changes to your diet talk to your health professional.

Foods that are rich in vitamin K
Vegetables Asparagus Broccoli Brussel sprouts Leafy greens such as cabbage, kale, lettuce, spinach, watercress, silverbeet Mung beans, green beans, peas, sugar snap peas Soybeans Chickpeas Other Liver Egg yolks Mature cheese and blue cheese	Fruit Avocados Kiwi fruit Blackberries Blueberries Raisins Drinks (known to affect warfarin) Green tea Cranberry juice Chamomile tea Grapefruit juice Pomegranate juice

Foods that are rich in vitamin K

Vegetables

Asparagus
Broccoli
Brussel sprouts
Leafy greens such as cabbage, kale, lettuce, spinach, watercress, silverbeet
Mung beans, green beans, peas, sugar snap peas
Soybeans
Chickpeas

Other

Liver
Egg yolks
Mature cheese and blue cheese

Fruit

Avocados
Kiwi fruit
Blackberries
Blueberries
Raisins

Drinks (known to affect warfarin)

Green tea
Cranberry juice
Chamomile tea
Grapefruit juice
Pomegranate juice

Alcohol affects your liver. If you are taking warfarin, it is fine to drink small amounts of alcohol. Generally, 1 to 2 standard drinks per day are considered a safe limit. Having more than this can increase your risk of bleeding. Avoid drinking large amounts of alcohol over a short time. Read more about what is a standard drink.

Some herbal or 'natural' products are known to have an effect on warfarin.
Always check with your doctor or pharmacist before taking herbal preparations or dietary supplements. Let them know if you are already taking supplements when warfarin is prescribed for you.

Examples of herbal or 'natural' products known to have an effect on warfarin
cannabis Chinese wolfberry chamomile tea chitosan co-enzyme Q10 cranberry dong quai echinacea fenugreek	fish oils (e.g. cod liver oil) ginkgo biloba garlic ginger ginseng glucosamine, green tea kava kava liquorice St John’s Wort