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Vitamin K & Blood Thinners


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  1. Do you know of any other foods that might have higher levels of vitamin K? Answer
  2. I have been on coumadin for 11 years. There are supplements I would really like to take, but they both contain vitamin K. Answer
  3. I am on Coumadin to thin my blood and prevent blood clots. I am having trouble regulating my dosage. Answer
  4. My mother is on a blood thinning medicine called "Coumadin". She had heard there is a diet that can help her while on this medication. Answer
  5. Is vitamin K a B vitamin? Answer
  6. My grandmother is having surgery and can't take her prescribed blood thinner. My family and I are looking for a natural herb or something to keep her blood thin. Answer
  7. Which foods are high in vitamin K? Answer
  8. I would like to know what foods are lower in vitamin K that are pure vegetarian (no meat, dairy, eggs). Answer
  9. My husband recently had a valve replacement. Are all lettuces equally high in vitamin K? Answer


  10. I was wondering if you could send me a listing of foods high in vitamin K with values i.e. micrograms (mcg). Answer
  11. I'm on a cardiac diet with Coumadin therapy - What foods should I avoid? Answer


Thanks to a response you gave a previous reader. I was able to copy the list of vegetables containing vitamin K. I am currently under a doctor's care for a clot in my jugular vein and take 8 milligrams of Coumadin daily. I avoid eating leafy greens, caffeine drinks and chocolate. Do you know of any other foods that might have higher levels of vitamin K?

You're welcome. The best list of vitamin K in foods is available from the USDA. The most important thing is maintaining a consistent intake of vitamin K as the coumadin dose will be consistent day to day. Your doctor will periodically measure your clotting time (prothrombin) to determine whether to increase or decrease your dose. So keep your intake of Vitamin K foods consistent day to day.


I would really appreciate your advice on the use of coumadin and vitamin K supplements. I have a genetic condition called Protein C Deficiency. I am 44 years old and have been on coumadin for 11 years. There are 2 supplement products on the market that I would really like to take, but they both contain vitamin K. One has 80 micrograms of vitamin K and the other 50 micrograms. I am receiving mixed advice from my doctors. My family doctor thinks it would be OK to try these products and watch my INR (prothrombin time) and increase the coumadin if necessary, but my hematologist says not take any supplement with vitamin K. An immunologist also thinks it would be OK to try the supplements. Please advise if you are able. Any information would be greatly appreciated.

It is confusing when doctors don't agree. Ask your doctors to talk to each other to reach a consensus on whether or not you should take a supplement with vitamin K. Until then, caution would be the better choice and not take a supplement with vitamin K. Ask a pharmacist at your favorite store for their recommendation of a supplement without vitamin K.

The biggest issue with coumadin and vitamin K is you need to eat a consistent amount of vitamin K containing foods every day. In other words, one day, don't eat lots of green leafy vegetables and the next few days go without. It would be more difficult to regulate your clotting time with varying vitamin K intakes. Go back and read the vitamin K topic as there is a list of high vitamin K foods. Try to eat about the same amount of vitamin K every day.


I am on Coumadin to thin my blood and prevent blood clots. I am having trouble regulating my dosage. My diet could be the problem. Could you send me a list of foods to avoid.

The USDA has the best list of foods with vitamin K. In the table below, choose foods that add up to less than your RDA (Recommended Dietary Allowance) for vitamin K (90 micrograms per day for women 19 to 70+ years or 120 micrograms per day for men 19 to 70+ years). Do not eat more than your RDA of vitamin K each day and try to eat a consistent amount from day to day.

Read below for what you need to know to regulate food intake which is influencing your clotting time (prothrombin). Just because you are on a blood thinner does not mean you should avoid all foods with vitamin K.


Thank you for having a site where questions may be answered. My mother is on a blood thinning medicine called "Coumadin". She had heard there is a diet that can help her while on this medication. Foods that might be low in iron perhaps?

The doctor never told her anything about controlling her diet in that respect. Any advice or information would be greatly appreciated.

Your mother does not need to restrict foods containing iron. She needs to eat foods with iron to maintain her red blood cell hemoglobin which carries oxygen around her body.

Vitamin K is needed for blood clotting and if your mother eats different amounts (high one day and low the next day) of vitamin K, it will be more difficult to regulate her clotting time. Remember that vitamin K is a fat soluble vitamin so it is stored in your body. If your mother is on Coumadin, she needs to eat enough foods containing vitamin K to meet her RDA (Recommended Dietary Allowance) which is 90 micrograms per day for women 19 to 70+ years of age. See table below for a list of foods with vitamin K.


In Canada, vitamin K is known by another name. I believe we refer to it as one of the B vitamins, but for the life of me, I can not remember which one. I'm hoping that you can turn that light bulb on for me. Thanks.

Canadians don't include vitamin K as a B vitamin. Since 1995, the U.S. and Canada have worked together to create the RDA's (Recommended Dietary Allowance) for vitamins and minerals.

Vitamin K comes in different forms including phyloquinone in plants and menaquinone in animal products in addition to a synthetic form menadione.

The known B vitamins are:

B1 Thiamin
B2 Riboflavin
B3 Niacin
B6 Pyridoxine
B12 Cobalamin


My Grandmother has in the past taken a commonly prescribe blood thinner. In the near future her doctor will be removing a fatty tumor located on her left shoulder towards the center of her neck. He required her to stop taking the blood thinners. My family and I are looking for a natural herb or something to keep her blood thin. She had heart surgery 1 year ago. Your advice will be greatly appreciated.

Your grandmother's doctor probably took her off the prescribed blood thinner (warfarin) so that she would not excessively bleed during and after surgery. This is standard practice. If she were to start taking an herbal blood thinner, she may excessively bleed during surgery and the doctor may not be able to stop the bleeding. Follow her doctor's advice and keep your grandmother off her prescribed blood thinner and don't substitute anything else to thin her blood. Make sure your grandmother informs her surgeon of all her medications (prescribed and over the counter) including vitamin, mineral and herbal supplements. Make sure that your grandmother's tumor surgeon is conferring with her heart surgeon as they may work in different hospitals or clinics.

Vitamin K promotes blood clotting. Ask your grandmother's doctor if there is any need to limit vitamin K foods pre or post surgery.


Which foods are high in vitamin K?

Leafy green vegetables (kale, collards, spinach, turnip greens, beet greens, mustard greens, dandelion greens green leaf lettuce), Brussels sprouts, broccoli, green onions, parsley, asparagus and sauerkraut contain more than the RDA of vitamin K for men or women. These foods are not allowed for persons with a history of blood clots and persons on blood thinning medication. See table below for a list of foods with vitamin K.


I would like to know what foods are lower in vitamin K that are pure vegetarian (no meat, dairy, eggs). I have a friend who's taking anti-coagulants and needs to reduce vitamin K in her diet. She is a pure vegetarian for ethical reasons, but must stay away from soy products, dark leafy green vegetables, etc. because of the vitamin K content. What foods are available to her for a balanced diet that is vegetarian and low in vitamin K? Thank you!

There is some misinformation that people on anticoagulants have to avoid all foods with vitamin K. What they need is a consistent amount of vitamin K each day that meets their RDA (Recommended Dietary Allowance) which is 90 micrograms per day for a woman ages 19 to 70+ years and 120 micrograms per day for men ages 19 to 70+ years.

Soy beans have about 1/3 of your friend's RDA for vitamin K, but should be limited to less than 2 cups of soybeans per day. Fortified soy milk is low in vitamin K so she can drink 3 cups per day to get her calcium and vitamin D. Tofu is low in vitamin K.

See table below for a list of vegetarian foods with vitamin K.


My husband recently had a valve replacement. He will be taking Coumadin for the rest of his life. I read your helpful info on vitamin K, but have one more question - are all lettuces equally high in vitamin K? He has been told he can eat some foods as long as it is done on a consistent basis and really loves salad.

The information on vitamin K content in foods is limited to less than 1,000 foods. If he were to eat lettuce, he should stick to iceberg especially the whiter inner leaves (1 cup has 13.3 micrograms vitamin K) or Romaine (1 cup has 57.4 micrograms vitamin K) as they are the lowest in the USDA data.

Would suggest he try salads made of other raw vegetables that are low to moderate sources of vitamin K like white mushrooms, corn, beets, radishes, red, yellow or orange peppers, cooked dried beans (chickpeas, garbanzo, pinto, navy or red kidney), avocado, onions other than scallions or Spring type, cucumbers (peeled), peas, edible pod peas, mung bean sprouts, tomatoes, red cabbage, carrots and potatoes.


Hi! I am a nutrition student doing an internship and one of my projects is to revise a Coumadin diet instruction sheet for patients. I was wondering if you could send me a listing of foods high in vitamin K with values i.e. micrograms (mcg). There has been some conflicting information on vitamin K in onions and onion soup. Any information you could send would be appreciated! Thank you.

Onions are OK for persons on Coumadin except for green or Spring type onions. Onion soup is most often made with yellow or white onions so it should be fine. A few green onions slices sprinkled on the top would not be a problem either.

Here is a table of vitamin K values (micrograms per serving) which you can also get from the USDA. I have selected foods high in vitamin K that people usually consume (excluding spices and herbs which are used in very small amounts). The Recommended Dietary Allowances for vitamin K for adult males is 120 mcg and for adult females 90 mcg.

Table: vitamin K in 1 cup serving:

Omit High Medium Low Very Low
90 to 1,150 mcg 60 to 90 mcg 30 to 60 mcg 10 to 30
mcg
5 to 10
mcg
kale okra Chinese cabbage tomato paste cashew nuts 1 ounce
collards cabbage lettuce romaine or cos mixed vegetables split peas
spinach rhubarb celery blackberries lima beans
turnip greens plums dried stewed coleslaw blueberries fresh squash winter
beet greens cowpeas or blackeye peas edible pod cabbage red prune juice
mustard greens cabbage Savoy plums dried 5 prunes mangos 1 fruit
Brussels sprouts cabbage artichokes duck (1/2 cooked)
broccoli blueberries frozen grapes red or green salad dressing Italian 1 tbsp
onions Spring or scallion pumpkin cauliflower salad dressing Russian 1 tbsp
dandelion greens peas green carrots beef stew
parsley 10 sprigs tuna fish in oil 3 ounces miso papaya 1 fruit
spinach noodles carrot juice cucumber peeled oat cereal cooked
asparagus spaghetti sauce yellow snap beans pears
sauerkraut mung bean sprouts green snap beans muffins oat bran
endive soybeans cooked vegetable soup soy milk
lettuce green leaf kiwi fruit 1 medium salad dressing French 1 tbsp peppers sweet red
French fried potatoes 1 large fast food serving soup split pea
cauliflower soup clam chowder
raspberries seaweed kelp 2 tbsp
biscuit with egg & sausage fast food (1) chickpeas or garbanzo beans cooked
salad dressing vinegar & oil 1 tbsp fruit cocktail
pine nuts peppers hot chili green
tomatoes fresh chives 1 tbsp
salad dressing blue or Roquefort 1 tbsp peppers hot chili red
bread stuffing 1/2 cup squash summer
turkey patties breaded battered fried 1 patty soup vegetarian vegetable
seeds pumpkin or squash roasted peaches dried 3 halves
lettuce iceberg refried beans
peppers sweet green pinto beans
vegetable juice cocktail avocado 1 ounce
potatoes mashed figs dried (2)
pickle relish 1 tbsp red kidney beans
Asian pear mayonnaise salad dressing 1 tbsp
pickles dill (1) potatoes hash brown
chestnuts apricots canned
plums purple canned sweet potatoes
salad dressing thousand island 1 tbsp tomato juice
alfalfa seed sprouts peaches frozen
fruit leathers 1 ounce
raisins
chili con carne
honeydew melon


I'm on a cardiac diet with Coumadin therapy - What foods should I avoid?

Coumadin is prescribed to prevent blood clots and increase the amount of time it takes your blood to form a clot. This allows the blood to flow more easily through narrowed blood vessels.

You should have a consistent intake of vitamin K (Recommended Dietary Allowance for men is 120 micrograms, women 90 micrograms per day). Avoid supplements with vitamin K as that would interfere with the amount of Coumadin needed to regulate your clotting time. Your clotting time will be periodically tested by your doctor to regulate this medication.

Foods high in vitamin K are green leafy vegetables (kale, collards, spinach, turnip greens, beet greens, mustard greens, dandelion greens), Brussels sprouts, broccoli, green onions, parsley, asparagus, sauerkraut and lettuce (endive and green leaf). Milk, meat, eggs and cereal contain small amounts. Vitamin K content in vegetables and fruits vary. See table above for a list of foods with vitamin K because vitamin K content of food is not usually listed on food labels. Vitamin supplements containing vitamin K are available by prescription.

You did not say what type of cardiac nutrition therapy you are supposed to follow. Are you on a low saturated fat, low trans fat , low fat / calorie reduced nutrition therapy? Please write back.








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