One of the the facts I emphasize during my integrative oncology talks is that the majority of patients with cancer do not die from their cancer, but instead from a side effect or complication related to their cancer or the cancer treatment.
- FACT: One in five cancer patients will develop a potentially life threatening blood clot within their first year of their diagnosis (and up to 50% by the time of death.)
This blood clot is called a DVT (deep vein thrombosis.) Typically, they develop in the veins of the arm, leg or pelvis, and they can present with swelling, pain, redness, warmth, or heaviness in the affected area.
If they dislodge and travel to the lung, heart or brain, they can become deadly. A VTE (venous thromboembolism) is the term used for any DVT that ends up in another part of the body.
- The most well known VTE is a PE (pulmonary embolism), a DVT that gets stuck in the veins of the lung and blocks critical blood flow to lung. This can present with shortness of breath, cough or chest pain. Without rapid diagnosis and treatment it can be fatal.
The increased risk of blood clots and cancer is not recent news…it’s been known since 1865!
It’s hard for me to imagine, but one study reported that more than one-quarter of oncologists believe cancer patients are not at increased risk for blood clots.
Who Is At Greatest Risk Of Developing A Blood Clot?
DVT’s occur much more commonly among those with certain risk factors:
- Having Cancer (some cancers are more associated with blood clots)
- Recent major surgery or trauma
- Having a central venous catheter
- Receiving drugs that increase the risk of blood clots (i.e. hormonal therapy, numerous chemotherapy drugs, white and red blood cell growth factors)Being obese or overweight
- Physical inactivity (read about Physical Activity and Cancer on our prior blog post)History of a prior stroke (or transient ischemic attack, TIA)
- prolonged hospitalization or bedrest are notorious risk factors…but even short periods (i.e. a few hours) of inactivity can increase your risk
- History of a heart attack or coronary artery disease (read about Cardiac Complications After Cancer on our prior blog post)
- History of a prior blood clot (or family history of blood clots)
- High blood pressure
- Having atrial fibrillation (and abnormal heart rhythm)
- High LDL and total cholesterol levels and/or low HDL levels (known risk factors for the development of atherosclerosis: clots often form in areas of arterial plaques on blood vessel walls)
- Having a low red blood cell count (anemia), having a high platelet count or having a high white blood cell count
- Elevated levels of homocysteine or high-sensitivity C-reactive protein (hsCRP)
- High blood sugar levels
- Drinking more than 1 serving of alcohol per day
- …and a variety of other conditions (i.e. thyroid abnormalities, pregnancy, high blood fibrinogen levels)
- Risk factor assessment model (for those with a diagnosis of cancer)
- PreventDVT.org risk calculator (for those with or without a diagnosis of cancer)
How Does Cancer Increase The Risk Of Blood Clots?
- Cancer cells produce blood clotting and inflammatory proteins that make the blood more likely to clot.
- Numerous medications used to treat cancer can increase the risk of blood clots.
- As a result of cancer or cancer treatment, many patients get out of shape, or have pain or limitations in their range of motion. This can lead to physical inactivity, increased obesity and systemic inflammation…all known risk factors for developing blood clots.
- A recent surgery or hospitalization is the most common risk factor for developing DVT’s (typically as a consequence of prolonged inactivity leading to pooling of blood in the legs and pelvis.
- When your legs remain still for long periods, your calf muscles don’t contract, which normally helps blood circulate. Blood clots can form in the calves of your legs if your calf muscles aren’t moving.
Here Are My Recommendations To Help Reduce The Risk Of Blood Clots:
- Increase physical activity:Maintain a healthy weight
- Exercise your legs frequently while you’re sitting
- Exercise regularly (goal: at least 30 minutes of moderate aerobic exercise, 5-days per week)
- Get up and walk around every 2 to 3 hours
- Stop smoking! (and avoid second-hand exposure)
- Reduce stress (read how stress increases inflammation on our prior blog post)
- Limit alcohol consumption to 1 serving per day (preferably red wine)
- Consume an anti-cancer/anti-inflammatory diet
- Consider taking a daily, low-dose (“baby aspirin”):
- Recent studies have reported that individuals who take a low-dose aspirin every day may reduce their risk of blood clots by 40%.
- Read our prior blog post on how taking “One Baby Aspirin Per Day Cuts Cancer Development, Metastases and Death!“
- The active ingredient in aspirin is a plant-derived compound called a “salicylate.” Instead of taking a baby aspirin, you could simply consume foods that have high salicylate content (as well as many anti-cancer and anti-inflammatory phytonutrients):
- Spices, herbs and others:
- Consume foods that are rich in vitamin E or omega-3 fatty acids (both of which have blood thinning properties and may reduce the risk of blood clots):
- Sources of omega-3 fatty acids include:
- Fatty fish (i.e. anchovies, salmon, lake trout, herring, mackerel) and fish oil
- Plant sources (i.e. flaxseed, sunflower seeds, canola oil, corn oil, safflower oil, soy)
- Vitamin E rich foods include:
- Nuts (i.e. walnuts, almonds, hazelnuts)
- Vegetable oils (i.e. canola oil, sunflower oil, palm oil)
- Lentils (i.e. chickpeas)
- Oats and wheat
- Sources of omega-3 fatty acids include:
- Other foods and supplements that reduce blood clotting:
Warning: As always, discuss with your doctor your risk of bleeding before taking aspirin or consuming large amounts of foods (or taking supplements) with anti-clotting activity.
- This is particularly of concern for anyone who is currently taking a blood thinning medication, has had bleeding problems (either excessive bleeding or slow blood clotting) or has recently undergone surgery (or is scheduled for an upcoming surgery.)
Vitamin K and Blood Clotting:
Did you know that one of the most important dietary factors involved in helping your blood to clot is vitamin K? Vitamin K is also essential in maintaining your bone density (preventing osteopenia or osteoporosis) and helping to prevent calcification of arteries.
Vitamin K is actually a group of fat soluble vitamins that includes vitamins K, K1, K2, and K3. Vitamin K1 (phytonadione) is the natural form of vitamin K, which is found in green vegetables and is the primary source of vitamin K that we obtain through foods. It is vitamin K1 that helps us maintain a healthy blood clotting system. Vitamin K2 is the form that is predominantly involved in maintaining our bone density and helps prevent accumulation of calcium in our artery walls. We obtain vitamin K2 through the bacteria in our gut (or through supplements, fermented cheeses and natto.)
You can obtain vitamin K1 from numerous dietary sources (see the table below).
- The recommended daily amount of vitamin K1 for adults is 250 mcg/day (an amount that is more than 2-times higher than the minimum daily requirement of 90-120 mcg/day)
Does taking too much vitamin K1 increase your risk of blood clots?
- No. There is no known increase risk of blood clots in individuals who take too much vitamin K1.
- One of the serious interactions that can occur with vitamin K1 is that of its ability to reduce the effectiveness of a common blood thinning medication, warfarin (or Coumadin.) In fact, vitamin K1 is used by physicians to reverse the effects of a warfarin overdose. If you are taking warfarin, the recommended daily dose of vitamin K1 should be limited to 90-120 mcg/day.
- Patients with the genetic blood clotting disorder “Factor 5 Leiden” have an increased risk of blood clots, and should not take supplemental vitamin K. Taking supplemental vitamin K could further increase the risk of blood clotting in these patients. Read more about this condition here.
Here’s a partial list of the medications that can reduce your blood levels of vitamin K:
- anti-seizure medications
- many antibiotics
- mineral oil
- olestra (fat substitute)
Caveat To The Non-Pharmacologic Approach: If you have had a prior blood clot, see a doctor to find out why…you may have an underlying condition that makes your blood clot more easily…
- Yes, I know that I titled this post “Reduce Your Risk Of Blood Clots Without A Prescription,” but if you already have a history of blood clots or a heart condition (i.e. atrial fibrillation) that predisposes you to blood clots, your physician will weigh the pros and cons of prescribing you a “blood thinning” medication.
Optimal Lab Values and Blood Pressure Levels To Minimize The Risk of Blood Clots:
- Lipid panel (cholesterol levels)
- Fasting blood glucose
- Homocysteine (a protein that predisposes to blood clots)
- Fibrinogen (a blood clotting factor)
- TSH (thyroid stimulating hormone: an indicator of thyroid function)
- CRP (c-reactive protein: an indicator of the level of systemic inflammation)
- blood pressure (measure this at 3 different times, when you are relaxed, and calculate the average)
- …additional laboratory tests may be ordered by your physician when indicated
Dr. Lawenda’s Bottom Line:
Adopting an anti-inflammatory lifestyle (i.e. exercise, diet, stress reduction, not smoking, etc.) is the best approach to decrease your risk of developing a potentially life-threatening blood clot.
If you want to take the extra steps to further reduce this risk, there are numerous foods and supplements that may help. Checking certain laboratory values and your blood pressure may be important for those who are already at risk of developing a blood clot.
Before making any major changes to your food or supplement routine, check with your physician on whether they agree this is safe and appropriate for you.