Report on Bay Side Effects and Usage

Bay Leaf

Natural health supplements sometimes have unexpected side effects or interactions with medication that can lead to adverse reactions that are sometimes life threatening. The following is a list of cautions that you should be aware of before using Bay Leaf (Laurus Nobilis). These are referred to as drug/herb interactions.

Warning 1 – Counterindications: Pregnancy.

Warning 2 – Antidiabetics: Using bay may increase hypoglycemic effects.

Warning 3 – Insulin: May increase the hypoglycemic effects of insulin.

Used as a natural health remedy: Bay is used internally for the following benefits and conditions:

  • Aid to digestion: Hot bay leaf tea can help alleviate common digestive disorders including constipation, acid reflux, irregular bowel movements, and it reduces gas. Bay leaves contain enzymes that play a role in the digestion of proteins, which make it an excellent spice for diets that are rich in meat. It also aids in the prevention of digestive disorders like irritable bowel syndrome (IBS), celiac disease, constipation etc.
  • Respiratory infections: Hot bay leaf tea is also used to relieve the symptoms of cold, cough, flu, and to reduce fever.
  • Anti-inflammatory: Bay leaf oil is massaged into the skin to reduce inflammation and pain resulting from arthritis, sprains, strains, and general pains and aches. (See other herbs for inflammation) This oil is also used to massage the temples for relieving migraines and headaches.
  • Antifungal and Antibacterial properties: Bay leaf oil is applied to the skin to treat skin infections and aid the healing of cuts, bruises and insect bites. Bay leaf extract has antimicrobial activity against some of the most common pathogens, including Streptococcus pyogenes, Staphylococcus aureus, Aspergillus fumigatus and Candida albicans. It speeds the healing of wounds.
  • Heart disease: Bay leaves contain valuable compounds, including caffeic acid, rutin, salicylates, and phytonutrients, which help enhance cardiovascular health and reduce the risk of heart disease. These phytonutrients prevent the formation of plaque in the arteries and lower the risk of atherosclerosis, stroke and heart attacks.
  • Cooking with bay leaves supplies vitamin and minerals to the diet; calcium, potassium, iron, manganese, and vitamins C.
  • Diabetes: Fresh bay leaves contain enzymes that trigger the production of insulin, which help regulate the level of blood sugar in the body. It controls and prevents the rise as well as the drop of blood glucose levels to help maintain an optimal level. Not only have bay leaves shown to improve insulin function but also it simultaneously improves markers for heart disease such as cholesterol and triglycerides.
  • GERD: Bay oil promotes the discharge of bile into the stomach, which helps maintain the balance of acid to base in it. This bile breaks down the complex food molecules and neutralizes excess acid that is discharged into the stomach, which can wear down the inner lining of the stomach, causing ulcers.
  • Dental: An extract, Eugenol, is made from bay leaves and is used to treat dental problems. Bay leaf oil is used as an analgesic to relieve the pain of toothaches.
  • Scalp problem: A few drops of bay leaf oil mixed with regular shampoo can help keep away dandruff. A solution of bay leaf and water also helps reduce scalp eczema and psoriasis.

Side Effects of Bay Leaves and Oil

The known side effects of using Bay include:

  1. Dried bay leaf has been reported to cause upper gastrointestinal tract bleeding in Slovenia. (Skok P. Maribor Teaching Hospital, Slovenia, Dried bay leaf: an unusual cause of upper gastrointestinal tract hemorrhage. Endoscopy. March 1998)
  2. Bay leaf oil contains eugenol, which can cause irritations in skin and mucus membrane.
  3. The use of bay leaves, oil, and/or extract may also cause asthma. (Lemière C, Cartier A, Lehrer SB, Malo JL. Sacré-Coeur Hospital, Montreal, Canada. Occupational asthma caused by aromatic herbs. Allergy. September 1996)

Other side effects may also occur when using Bay. (See form below)

Caution: There are several types of plants that are called bay leaves, but only Laurus nobilis is the true bay leaf. Leaves from other plants do not have the same health benefits and some are toxic. According to the Herb Society of America, the Kalmia latifolia is poisonous, even though it is related to and looks like the bay leaf. Leaves of the California laurel are sometimes sold as “California bay leaves” but they can cause respiratory distress when inhaled and damage the central nervous system.

As with any herb, a serious allergic reaction is possible. Seek immediate medical attention if you notice any symptoms of a serious allergic reaction. These may include a rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, or trouble breathing.

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For questions and answers about the side effects of herbs see the Herb Forum

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