If you have an upcoming medical procedure scheduled, your doctor has likely mentioned specific foods, supplements and vitamins not to take before surgery. Even minor procedures may require these dietary changes, because certain products can increase your risk of bleeding and complications.
Stopping Vitamins Before Surgery
Although vitamin supplements are often a healthy choice, there are several you'll need to avoid before surgery. In particular, you need to avoid taking vitamins that may affect or alter your body's ability to clot blood. There is also some concern that your vitamins and supplements may interact with other medications you're taking, affect your cardiovascular health or prolong the effects of anesthesia.
For instance, vitamin E is an essential nutrient that also acts as an antioxidant. This nutrient also contributes to a healthy immune system and cardiovascular system function. However, the National Institutes of Health have reported that large amounts of vitamin E can increase your risk of bleeding, especially if your vitamin K levels are low.
The American Society of Anesthesiologists and Stanford University School of Medicine's Department of Otolaryngology specifically recommend avoiding vitamin E before surgery because it can increase the likelihood of bleeding and cause issues with your blood pressure. You may need to stop taking this nutrient up to seven days before surgery.
Stanford University School of Medicine's Department of Otolaryngology also recommends avoiding vitamin C before surgery. This nutrient may interact with a variety of medications like antiviral drugs and blood thinners. You should consult with your doctor about potential interactions between nutrient supplements and any medications you're currently taking or may need to take following your surgery.
Supplements to Avoid Before Surgery
Many supplements have the potential to cause negative side effects during or after surgery. The American Society of Anesthesiologists warns against taking supplements like:
- Ephedra, an appetite suppressant that can negatively alter blood pressure and heart rate.
- Gingko, a cognitive enhancer that can increase your risk of bleeding.
- Ginseng, a cognitive enhancer that can increase your heart rate and risk of bleeding.
- Kava, an anti-anxiety supplement that can prolong the effects of anesthesia.
- St. John's wort, an anti-anxiety, anti-depressant and sleep-enhancing supplement that may prolong the effects of anesthesia.
- Valerian, a sleep aid that can prolong the effects of anesthesia.
In addition to these supplements, Stanford University School of Medicine's Department of Otolaryngology says you may need to stop taking certain medications like antiplatelet, blood thinning and anti-inflammatory drugs based on your health care practitioner's recommendations.
You should also avoid herbs and spices like:
- Birch bark
- Chinese black tree fungus
- Evening primrose oil
- Grapeseed extract
- Milk thistle
- Omega-3 fatty acids (polyunsaturated fatty acids)
Sometimes, your doctor may ask you to continue taking your medications but make dietary changes. These changes are extremely important because of the interaction between certain medicines and supplements or foods.
Diet, Medications and Surgery
A May 2013 study in PLOS One reported that many herbs, spices and supplements can produce negative and harmful interactions in combination with anticoagulant and antiplatelet drugs. This study found that a variety of foods and supplements — including celery, chamomile, evening primrose, fenugreek, garlic, ginger, ginkgo, horse chestnut, licorice, red clover, turmeric and willow — can produce serious cardiovascular side effects when taken with medications.
You'll notice that many of these are the same products that the American Society of Anesthesiologists and Stanford University School of Medicine's Department of Otolaryngology also recommend avoiding. However, some of these products are harmful even on their own.
Garlic, onion and curcumin, a polyphenol found in turmeric, have strong anticoagulant and antiplatelet activity. A June 2013 study in the International Journal of Woman's Health reported that large amounts of garlic have resulted in excessive bleeding during different surgical procedures. When garlic is combined with blood thinning medications, more serious side effects, like a cerebral hemorrhage, are possible.
The same study reported that consumption of gingko produced severe bleeding following procedures like liver transplants, gallbladder removal and hip surgery. Gingko produces this issue on its own, rather than in combination with any medication.
A March 2012 study in the Aesthetic Surgery Journal warned against other herbal and dietary supplements that have the potential cause bleeding complications. These include:
- Baical skullcap root
- Bromelain (found in pineapples)
- Chinese agrimony
- Chinese peony
- Fritillaria bulbs
- Dan shen
- Devil's claw
- Geum japonicum
- Japanese honeysuckle
- Wintergreen oil
- Red chili peppers (and anything else containing capsaicin)
- Saw palmetto
- Fish oil
Taking Fish Oil Before Surgery
Taking fish oil before surgery is a little complicated. Although the Aesthetic Surgery Journal study recommends against it and Stanford University School of Medicine's Department of Otolaryngology also warns against taking omega-3 fatty acids, fish oil is full of healthy, unsaturated fats. These fats are known to be good for your health, particularly the health of your heart.
Fish oil is specifically thought to be bad as it contains eicosapentaenoic acid (EPA), a type of omega-3 fatty acid that is commonly found in fish and other seafood products. You can also obtain EPA from algae-based supplements, marine plants and eggs that have been fortified with omega fatty acids. In large amounts, taking fish oil or omega supplements before surgery could be unsafe, because EPA has the potential to produce antiplatelet effects.
The Aesthetic Surgery Journal study reported that fish oil consumption could be detrimental because it has the potential to prolong bleeding and increase the risk of hematomas after surgery. However, a May 2014 study in the British Journal of Nutrition found that this is not the case. This study reported that consumption of these unsaturated fatty acids actually could help improve surgical outcomes.
The National Institutes of Health and Food and Drug Administration currently maintain the stance that fish oil is safe. However, people who are taking blood thinning medications, like warfarin, may need to check in more regularly with their healthcare providers.
If you consume a lot of omega fatty acids or take omega supplements, talk with your healthcare practitioner about your diet. She'll be able to advise you on whether or not it's safe to take omega supplements like fish oil before surgery.
- NIH: "Omega-3 Fatty Acids Fact Sheet for Health Professionals"
- British Journal of Nutrition: "N-3 Fatty Acids Affect Haemostasis but Do Not Increase the Risk of Bleeding: Clinical Observations and Mechanistic Insights"
- Aesthetic Surgery Journal: "Bleeding Risks of Herbal, Homeopathic, and Dietary Supplements: A Hidden Nightmare for Plastic Surgeons?"
- International Journal of Woman’s Health: "Be Wary of “Natural” Therapy in Gynecological Surgery"
- BMB Reports: "Anticoagulant Activities of Curcumin and Its Derivative"
- PLOS One: "A Review of Potential Harmful Interactions between Anticoagulant/Antiplatelet Agents and Chinese Herbal Medicines"
- Mayo Clinic: "Vitamin C"
- Stanford University School of Medicine Department of Otolaryngology: "Medications and Herbs That Affect Bleeding"
- American Society of Anesthesiologists: "Herbal and Dietary Supplements and Anesthesia"
- NIH: "Vitamin E Fact Sheet for Health Professionals"