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The interpretations below are provided by Donna Castellone, MS, MT (ASCP) SH for Aniara Diagnostica.

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Here we go again, no matter what you celebrate, we are entering a food marathon with people consuming up to 7000 calories on a holiday! Yikes- so of course that makes you wonder; how does that affect clotting or bleeding? This can be especially important for people on anticoagulants and anti-platelet drugs, as well as your waistline! Spices and herbs were used as a medicine and food preservative in Egypt, Asia, Greece and Rome. The use of spices as medications and food flavors continued in the Middle Ages. No food directly thins the blood the way that medications do, but it is important to be aware of what can enhance or minimize risk for a blood clot.

FOODS AND CLOTTING:

Foods high in vitamin E and low in vitamin K such as almonds and hazelnuts can cause issues with delayed clotting. One tablespoon of wheat germ contains 100% of your daily value! On the flip side, increasing foods with vitamin K can counteract the action of warfarin, which is a vitamin K antagonist. This is found in brussels sprouts, chard, spinach, kale, green tea, collard greens parsley and mustard greens. It is also found in broccoli, cauliflower, egg yolk and soybeans.¹

Olive oil was looked at in a study in people with a BMI over 30, consuming olive oil at least once/week decreased platelet activity, and was greater when they consumed it more than four times/week. The exact amount wasn't measured. Virgin olive oil is rich in phenols which can impact clotting.² A small study compared subjects with high cholesterol who ate white bread with 40 ml virgin olive oil containing 400 parts per million of phenols and compared it to 80 PPM of phenol. Plasma concentrations of lipid fractions, factor VII antigen, activated factor VII, and plasminogen activator inhibitor-1 activity were measured at baseline and postprandially. Concentrations of FVIIa increased less (P = 0.018) and plasma PAI-1 activity decreased more (P = 0.021) 2 h after the high-phenol meal than after the low-phenol meal. FVIIa concentrations 120 min after intake of the olive oil with a high phenol content correlated positively with fasting plasma triacylglycerols (P = 0.001). A virgin olive oil with a high content of phenolic compounds changes the postprandial hemostatic profile to a less thrombogenic state.³ Extra virgin olive oil (EVOO) contains higher levels of phenols and well as the healthier polyunsaturated fatty acids and may be more preventative with blood clots and regulate blood pressure.²

HERBS AND SPICES AND CLOTTING:

Several herbs can also promote bleeding such as cayenne, garlic, ginger and onion. Also dong quai, green tea, St John's wort, and white willow bark. Nattokinase is a strong anticoagulant, however you would have to ingest large amounts to have an anticoagulant effect, but there could be a significant effect if taken as supplements. Did you know that cranberry juice increases the amount of salicylic acid in the body? Fatty fish, such as salmon, mackerel and tuna, contain a significant amount of omega-3 fatty acids and may increase the risk of bleeding.¹

Herbal supplements have been on the rise and several have the potential to interfere with blood clotting. The majority (45%) of supplements have antiplatelet properties, up to 15% have anticoagulant properties and 15% have a combination of antiplatelet and anticoagulant properties.⁴

Supplements are not regulated and can have differences in manufacturing. Warfarin is more concerning regarding food interactions than DOACs.⁵

Table 1. Summary of reported effects of herbal supplements on blood clotting and their potential interactions with medications having blood-thinning properties⁴

Herbal supplements	Effects on blood clotting and potential mechanisms	Potential interactions with anti- platelet/blood-thinning medications
Antiplatelets
Aloe	Certain chemical constituents, including salicylate, cause inhibition of platelet aggregation, and increased bleeding during/after surgery.	Enhanced bleeding with the general anesthetic, sevoflurane, during surgery; no report of interactions with antiplatelet and other blood-thinning medications.
Cranberry	Constituents include salicylic acid with potential antiplatelet activity, but this activity has not been verified, and there are no reports of the effect on hemostats.	Increased bleeding with warfarin, but no reports of interactions with medications having antiplatelet properties.
Feverfew	Certain components, especially parthenolide, inhibit platelet aggregation by inhibiting phospholipase A2 and arachidonic acid metabolism, but no reports of effects on blood clotting/bleeding.	No evidence of interactions with blood-thinning medications, including those with antiplatelet properties.
Garlic	Certain constituents inhibit platelet aggregation and induce bleeding under different conditions by inhibiting production/release of various mediators including TXA2, ADP, PAF, and adenosine.	Augments antiplatelet and anticoagulant effects of aspirin/NSAIDs and warfarin, respectively, with increased risk of bleeding. Should not be used 7-10 days prior to surgery
Ginger	Certain constituents reduce platelet aggregation by inhibiting synthesis of TXA2, with the potential to increase bleeding.	Increased bleeding with warfarin, but no evidence of interactions with medications with antiplatelet properties. Contains salicylates.
Ginkgo	Certain components, particularly ginkgolides, inhibit platelet aggregation and cause bleeding by inhibiting PAF formation and binding to its receptors on platelet membranes.	Results in increased risk of bleeding with aspirin-like analgesics with antiplatelet effects. Some clot busting properties
Meadowsweet	Constituents such as salicylate reported to produce antiplatelet activity by inhibiting effects of PAF, but no reports of alteration in blood clotting or hemostasis.	No reports of interactions with antiplatelet or other blood-thinning medications.
Turmeric	Certain components, especially curcumin, inhibit platelet aggregation by inhibiting arachidonic acid metabolism and TXA2 synthesis, but no evidence of causing bleeding.	No reports of interactions with antiplatelet or blood-thinning medications. Contains a derivative, curcumin which is similar to coumadin.
White willow	Certain salicylate-like components, reported to inhibit platelet aggregation, but no report of effects on blood clotting.	No reports of interactions with antiplatelet or blood-thinning medications.
Anticoagulants
Chamomile	Among multiple constituents, it contains coumarins, but has not been shown to affect blood clotting when used alone.	Causes increased bleeding in the presence of warfarin, but interactions with other blood thinners is unknown.
Fenugreek	Among multiple constituents, it contains coumarins, but has not been shown to affect blood clotting.	No reports of interactions with blood-thinning medications.
Red clover	Among multiple constituents, it contains coumarins, but has not been shown to affect blood clotting.	No reports of interactions with blood-thinning medications.
Antiplatelets and anticoagulants
Dong quai	Certain components, particularly coumarins and ferulic acid cause anticoagulant and antiplatelet effects, respectively; ferulic acid causes increased bleeding by inhibiting release of serotonin (5-HT) and ADP.	Increased risk of bleeding with warfarin, and potentially with other blood thinners, including aspirin and NSAIDs.
Evening primrose	Constituents contain fatty acids, including gamma (γ)-linolenic acid, believed to be associated with reduction of TXA2 and platelet aggregation, and increased bleeding time (slowing clotting).	Increased risk of bleeding or slowing clotting with blood-thinning medications, including aspirin, NSAIDs, and warfarin.
Ginseng	At least some constituents have antiplatelet effects with the risk of causing increased bleeding via inhibition of TXA2; reported to cause inconsistent anticoagulant effect.	No reports of interactions with antiplatelet medications, but inconsistent effects on anticoagulant action of warfarin,
Other herbal products
Flaxseed	Alpha (∝)-linolenic acid component hypothesized to alter platelet membrane composition with potential effect on hemostasis.	Potentiation of effects of medications with antiplatelet and anticoagulant properties.
Grapefruit	Furanocoumarin component reported to inhibit certain cytochrome P450 (CYP), but no reports of effect on blood clotting.	No reports of evidence of interactions with antiplatelet medications, but increases the anticoagulant effect of warfarin by inhibiting its metabolism.
Green tea	Certain components, particularly vitamin K and catechin, reported to have procoagulant and antiplatelet properties, respectively; antiplatelet effect reported to reduce/stop blood clots by inhibiting arachidonic acid metabolism and TXA2 formation.	No reports of evidence of direct interactions with antiplatelet medications, but counteracts blood-thinning effect of warfarin.
Oregano	Limited observations suggest certain constituents have the potential to induce bleeding and exacerbate bleeding disorders.	No reports of evidence of interactions with antiplatelet or blood-thinning medications.
Saw palmetto	Certain unidentified component(s) inhibits COX and arachidonic acid metabolism, but no impairment of platelet aggregation or alteration of hemostasis reported.	Increased risk of bleeding with warfarin, but no report of interactions with other blood-thinners.

TXA₂ thromboxane A₂, ADP adenosine diphosphate, PAF platelet-activating factor, 5-HT 5-hydroxytryptamine, CYP cytochrome, NSAIDs nonsteroidal anti-inflammatory drugs, COX cyclooxygenase⁴

The effect of ginger seems to be impacting platelet aggregation. However, most studies looked at people who consumed it daily and up to 2-3 times/day with serving size ranging from 3.6-5 g. Dietary supplementation of 100 g butter in 20 healthy male volunteers for 7 days was found to enhance platelet aggregation to a significant extent (P < 0.001). Addition of 5 g of dry ginger in two divided doses with fatty meal (in 10 individuals) significantly (P < 0.001) inhibited the platelet aggregation induced by ADP (adenosine diphosphate) and epinephrine, while in the placebo control group (10 individuals), there was no significant alteration in platelet aggregation. Serum lipids, however, remained unchanged in both the groups.⁶

Garlic has several health benefits, and a study has supported that ingesting small amounts over time may help prevent the formation of blood clot. This study had subjects eating one clover of garlic for 16 weeks, which led to an 80% reduction in thromboxane.² Cinnamon contains coumarin which can aid in preventing blood clots some studies state that consuming 2-6g of cinnamon a day may protect against heart disease and lowering blood glucose levels.²

RISKS WITH COFFEE, TEA, SODA AND ALCOHOL:

The INTERSTROKE study showed that consumption of more than 4 cups of coffee daily was associated with a significantly increased risk of all strokes (OR 1.37) while low to moderate coffee had no link to stroke risk. Tea consumption was associated with a lower risk of stroke (OR 0.81). Both were associated with a reduced risk for stroke and dementia with the biggest benefit from consuming both coffee and tea. In subjects, those who consumed 2-3 cups of coffee and 2-3 cups of tea had a 30% decrease in stroke and 28% lower risk of dementia. This protective effect may be due to flavonoids and their antioxidant and anti-inflammatory properties, however sweetening with sugar should be minimized.⁷

There is a 16% increased risk of stroke with one or more daily serving of sugar-sweetened or low-calorie soda per day (vs none), independent of established dietary and non-dietary cardiovascular risk factors. In the Women's Health Initiative Observation Study noted a higher intake of artificially sweetened beverages was associated with increased risk for all stroke (adjusted hazard ratio, 1.23, ischemic stroke 1.31), coronary heart disease (1.29) and all-cause mortality (aHR, 1.16). While the Framingham Heart Study showed a consumption of one can of diet soda or more each day was associated with an almost three-fold increased risk for stroke and dementia over a ten year follow up. Total artificial sweetener intake from all sources was associated with an increased risk for cardiovascular risk. However, all these studies have limitations and are observational and can be compounded by diet and lifestyle activities. A daily diet soda is most likely fine.⁷

ALCOHOL:

A meta-analysis showed that up to one drink per day was associated with a reduced risk for ischemic stroke, but heavy drinking which is more than two drinks per day significantly increased the risk for both ischemic and hemorrhagic stroke. This was also seen in young people who are heavy drinkers. The INTERSTROKE study demonstrated high to moderate consumption correlated with an increased stroke risk, but low consumption, had no risk. However, the study was based on self-reporting and may be attributed to other healthy behaviors that may counteract this risk.⁷

A study that looked at both human and animal models found that red wine decreased platelet aggregation. The results showed that aggregation of platelets from healthy subjects induced in vitro by collagen (5 microg/ml), thrombin (0.33 units/ml), and ADP (4 microM) was significantly inhibited by 10-1000 microM resveratrol, in a concentration-dependent manner.⁸

This was believed to be due to polyphenol content like resveratrol and its antioxidant effects. Resveratrol is a chemical found in red wine and it is associated with lower HDL cholesterol level, however its' exact mechanism on how it works is not well understood. The same result was found from drinking grape juice for 14 days.²

A study that looked at alcohol, rather than wine, suggests that having two drinks is associated with a decrease in fibrinogen. 30 g of alcohol a day was associated with a 7.5 mg/dl (−17.7 to 32.7) decrease in fibrinogen concentration, a 1.25 ng/ml (−0.31 to 2.81) increase in tissue type plasminogen activator antigen concentration, and a 1.47% (−1.18 to 4.42) increase in plasminogen concentration. Lp(a) lipoprotein—a lipoprotein particle that may affect the fibrinolytic cascade—was only assessed in four studies (five data records) and was modestly, and non-significantly, decreased by 0.70 mg/dl (−3.38 to 1.99) for each 30 g increment of alcohol a day.⁹ Heavy or binge drinking alcohol (greater than 4 drinks) can cause rebound thrombocytosis but this effect is not seen after drinking wine.

Drinking too much increases blood clotting problems through several mechanisms.

• Liver damage: Alcohol is processed through the liver, and excessive drinking damages this organ. The liver is a primary source where coagulation factors are produced, and liver damage can reduce the ability for production. ¹⁰
• Platelets: Too much alcohol increases platelets in the blood, so they are more likely to clot randomly. It also activates platelets, meaning they are more likely to begin forming clots. Long-term, excessive drinking causes long-term, consistent platelet activation.¹⁰
• Weight gain: Alcohol has a lot of calories, and even among those who choose to drink too much rather than eat meals, there is an elevated risk of gaining body fat. Having more body fat means there are more lipids in the blood, which increases the risk of developing blood clots.¹⁰
• Sedentary lifestyle: People who sit for a long time, especially on planes, increase their risk of blood clots in general. Adding alcohol to 12-hour flight or a sedentary job adds to the risk of blood clots.¹⁰
• Gender differences: Excessive drinking increases the risk of AF in both men and women, but it is a more significant increased risk for men. AF can trigger blood clots and lead to a stroke or heart attack. Women on hormonal birth control (HBC) who consume excess alcohol are at a very high risk for blood clots. HBC alone by itself increases clotting factors by 170 percent while decreasing anticoagulant factors by 20 percent.¹⁰
• Strokes: Drinking more than two servings of alcohol per day increases the risk of a stroke, which can be caused by a blood clot in the brain, by 50 percent. The risk of hemorrhagic strokes also increases. These strokes are not caused by blood clots, but by fewer platelets.¹⁰

The AHA/and ASA recommend a maximum of 2 drinks per day for men and one for women to reduce stroke risk, however there is also data supporting the risk for cognitive impairment. It increases the risk for CVD, cancer, cognitive decline as well as other issues. The data on alcohol and risk is scattered in particular since most studies rely on self-reported data from observational cohorts. It is not clear if moderation is beneficial, detrimental, or null with respect to health.¹⁰

CANNABIS:

There is evidence that cannabis and CBD can interact with certain medications, including blood thinners. It can inhibit platelet production, leading to an increased risk of bleeding, decrease the effects of antiplatelet medications by slowing down the metabolism and increasing the risk for a cardiac event, increase the effects of warfarin, resulting in a higher INR and an increased risk of bleeding as well as increase the effects of DOACs by slowing down the metabolism of the medication and increasing your risk for bleeding.⁵

CONCLUSION:

Well, I am not sure if I have given you good information or depressed you! Regardless, understanding how food and drink can impact bleeding and clotting is relevant and can be extremely important in those taking anticoagulants and antiplatelets.

Everything in moderation is the key. I will still have my occasional glass of diet soda, my cookies and yes my wine and vodka!

Whatever you celebrate, I wish you all the best to you and your family as we close out 2024 and bring in 2025. Most of all I wish you and yours health and happiness.

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REFERENCES:

1. Chrystal Doucette, Foods that Affect Blood Clotting, 28 November, 2018, https://healthfully.com/foods-that-affect-blood-clotting-7907820.html
2. Davis, C., Golden, KE., 6 foods that may help prevent Blood Clots and a few to Avoid, January 8, 2024. https://www.goodrx.com/conditions/deep-vein-thrombosis/foods-prevent-blood-clots
3. Juan Ruano, José López-Miranda, Rafael de la Torre, Javier Delgado-Lista, Javier Fernández, Javier Caballero, María Isabel Covas, Yolanda Jiménez, Pablo Pérez-Martínez, Carmen Marín, Francisco Fuentes, Francisco Pérez-Jiménez,Intake of phenol-rich virgin olive oil improves the postprandial prothrombotic profile in hypercholesterolemic patients2,The American Journal of Clinical Nutrition,Volume 86, Issue 2,2007,Pages 341-346.
4. Abebe, W., Review of herbal medications with the potential to cause bleeding: dental implications, and risk prediction and prevention avenues, EPMA, 2019 Jan 8;10(1):51–64, https://pmc.ncbi.nlm.nih.gov/articles/PMC6459456/
5. Lech, T., Food for Thought: Vitamins, Diet, and Anticoagulation https://thrombosis.org/2020/12/food-for-thought-vitamins-diet-and-anticoagulation/ July 22, 2021
6. Verma SK, Singh J, Khamesra R, Bordia A. Effect of ginger on platelet aggregation in man. The Indian Journal of Medical Research. 1993 Oct;98:240-242. PMID: 8119760.
7. Brews, Bubbles, & Booze: Stroke Risk and Patients’ Favorite Drinks. https://www.medscape.com/viewarticle/brews-bubbles-booze-stroke-risk-and-patients-favorite-drinks-2024a1000k6e
8. Wang Z, Huang Y, Zou J, Cao K, Xu Y, Wu JM. Effects of red wine and wine polyphenol resveratrol on platelet aggregation in vivo and in vitro. Int J Mol Med. 2002 Jan;9(1):77-9.
9. Rimm E B, Williams P, Fosher K, Criqui M, Stampfer M J. Moderate alcohol intake and lower risk of coronary heart disease: meta-analysis of effects on lipids and haemostatic factors BMJ 1999; 319
10. Reduced or Increased Risk of Blood Clots Due to Drinking, October 25, 2022.

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