Some herbal teas can even cause miscarriage!
Too much linden causes dizziness!
Experts emphasize that winter teas, which are beneficial for health, should be consumed carefully in cases such as allergic reactions, autoimmune diseases, pregnancy, breastfeeding, liver diseases, and drug interactions, stating that some herbs can increase the risk of miscarriage during pregnancy.
Dr. Öğr. Üyesi Tuğba Kaman also explained that due to their herbal components, winter teas can interact with some medications and cause undesirable side effects, saying, “It is important for individuals using anticoagulants, hypoglycemic drugs, antihypertensive drugs, and sedative drugs to consume these herbal teas carefully and consult a healthcare professional.” Dr. Öğr. Üyesi Tuğba Kaman added, “Linden, known for its calming and relaxing properties, can lead to sedation, drowsiness, and dizziness when consumed in excess.”
Dr. Öğr. Üyesi Tuğba Kaman, Head of the Medicinal and Aromatic Plants Program at Üsküdar Üniversitesi Vocational School of Health Services, evaluated who should avoid consuming winter teas, which see increased consumption in winter.
Some herbs may increase the risk of miscarriage during pregnancy
Dr. Öğr. Üyesi Tuğba Kaman noted that winter teas are herbal teas often preferred to alleviate symptoms of illnesses like colds and flu. She said, “However, these teas can be problematic for individuals with certain health issues. In those with stomach and digestive problems, excessive consumption of some herbs can irritate the stomach and cause a burning sensation in people with acidic stomach problems. For example, mint, which can be found in winter teas, can trigger heartburn and acid reflux; thyme can worsen some stomach problems; and individuals with conditions like stomach ulcers or gastritis are advised to avoid ginger. Some herbs can increase the risk of miscarriage during pregnancy. It has been stated that high amounts of ginger, which is commonly used to alleviate nausea, may pose a risk of miscarriage. Additionally, in individuals with bleeding disorders and those using anticoagulants, excessive use of herbs such as ginger, cinnamon, and thyme can affect blood clotting processes and trigger bleeding disorders.”
Individuals with a history of hormone-sensitive cancer should use chamomile with caution
Dr. Öğr. Üyesi Tuğba Kaman stated that thyme can interact with antihypertensive drugs and lower blood pressure in individuals with blood pressure problems, especially those with high blood pressure. She added, “Cinnamon can interact with antidiabetic drugs, causing an excessive drop in blood sugar. Therefore, it is important for individuals with diabetes to be cautious about cinnamon consumption and monitor their blood sugar levels. Moreover, high amounts of cinnamon consumption can have negative effects on the liver. Chamomile, known for its antiviral, anti-inflammatory, and calming properties, may contain compounds that can affect hormones, so individuals with a history of hormone-sensitive cancer should use it with caution.”
Linden can cause allergic reactions in some individuals
Dr. Öğr. Üyesi Tuğba Kaman also said that echinacea, an immune-boosting herb often used against colds, can cause allergic reactions or side effects in some individuals. She continued, “In individuals with autoimmune diseases (e.g., lupus, rheumatoid arthritis), echinacea can further activate the immune system, which may lead to a flare-up of the disease. There is a risk of allergic reactions for individuals sensitive to flower pollen. For example, linden can cause allergic reactions in some people. Caution is advised as the effects of many herbs on children have not been sufficiently studied.”
Winter teas can interact with some medications, causing undesirable side effects
Dr. Öğr. Üyesi Tuğba Kaman also explained that winter teas, due to their herbal components, can interact with some medications and cause undesirable side effects, and continued:
“Winter teas containing herbs such as ginger, elderberry, thyme, sage, chamomile, cinnamon, and clove can interact with anticoagulants (e.g., warfarin, aspirin, heparin) and antiplatelet drugs, affecting blood clotting mechanisms and increasing the risk of bleeding. Herbs like cinnamon, clove, and sage can increase the risk of hypoglycemia in individuals using insulin or oral antidiabetic drugs (e.g., metformin), leading to dangerously low blood sugar levels. Herbs such as thyme, ginger, and linden can interact with antihypertensive drugs, causing an excessive drop in blood pressure. Linden and chamomile, which have calming and sleep-inducing properties, can interact with sedative drugs such as benzodiazepines (e.g., diazepam, lorazepam), barbiturates, and sleep medications, causing excessive sedation, dizziness, and drowsiness.”
Those using blood pressure medication should consume herbal teas carefully
Dr. Öğr. Üyesi Tuğba Kaman also explained that some herbs, especially cinnamon and thyme, can affect serotonin levels, and therefore their use with antidepressant medications should be cautious. She said, “Licorice root, which has anti-inflammatory and antiviral properties, can interact with drugs used in the treatment of hypertension. Mint, an refreshing and antimicrobial herb frequently preferred in the treatment of problems such as colds, sore throats, and digestive issues, can increase stomach acid, which can be problematic, especially for individuals using antacid medications. Some herbs like echinacea and elderberry can stimulate the immune system and interact with immunosuppressive drugs (e.g., steroids or immunosuppressants), reducing treatment efficacy. It is particularly important for individuals using anticoagulants, hypoglycemic drugs, antihypertensive drugs, and sedative drugs to consume these herbal teas carefully and consult a healthcare professional.”
Can cause miscarriage and premature birth in pregnant women
Dr. Öğr. Üyesi Tuğba Kaman stated that pregnancy and breastfeeding are very sensitive periods for maternal and infant health. She said, “It is reported that excessive consumption of ginger, which is commonly used for nausea during pregnancy, can be associated with adverse outcomes such as miscarriage risk or premature birth. Furthermore, excessive use of ginger (more than 1 gram daily) is not recommended as it can increase the risk of bleeding. For breastfeeding mothers, caution is advised with excessive consumption of ginger, as it can affect the baby's digestive system and cause stomach problems like colic. Cinnamon, due to the coumarin it contains, can trigger uterine contractions when used in high doses, which can pose a risk of miscarriage or premature birth. During breastfeeding, excessive use of cinnamon can affect the baby's digestive system and cause some allergic reactions. Thyme and sage are also herbs that should be used sparingly during pregnancy. Like cinnamon, they can increase uterine contractions, which can lead to premature birth during pregnancy.”
Ginseng is known to raise blood pressure
Dr. Öğr. Üyesi Tuğba Kaman stated that some herbs can have negative effects on heart health, causing changes in blood pressure, and continued:
“Teas containing such herbs can generally have blood pressure-lowering or-raising properties, which can affect the bioavailability of medications used and thus treatment processes. Furthermore, herbal teas can interact with antihypertensive drugs, anticoagulants, or cardiac medications, causing serious side effects. In individuals undergoing hypertension treatment, thyme and ginger can interact with antihypertensive drugs, excessively lowering blood pressure and leading to hypotension. Rosemary, which has blood circulation-boosting properties, can also lead to excessively low blood pressure when combined with antihypertensive drugs and may pose some risks for cardiovascular diseases. Ginseng, known for its energy-boosting and immune-strengthening properties, is suggested by some studies to be able to raise blood pressure and pose serious risks for hypertension patients. It is very important for individuals with hypertension or heart disease to consult their doctors before regularly consuming any herbal tea.”
Too much linden causes dizziness
Dr. Öğr. Üyesi Tuğba Kaman stated that excessive consumption of herbs such as ginger, thyme, and cinnamon can cause stomach and digestive problems like nausea, diarrhea, and abdominal pain, and that cinnamon can trigger stomach problems like gastritis or ulcers in some individuals. She concluded, “Linden, known for its calming and relaxing properties, can lead to sedation, drowsiness, and dizziness when consumed in excess. This situation can be risky in tasks requiring attention. Cinnamon, which has metabolism-boosting and anti-inflammatory properties, can cause liver toxicity when taken in high doses due to the coumarin it contains, impairing liver function. Fennel, an herb beneficial for digestive system problems, contains estrogen-like compounds, so when taken in excessive amounts, it can disrupt hormonal balance. This can pose a risk, especially for individuals with a history of hormone-sensitive cancer (e.g., breast cancer). And the high-dose use of all these herbs can negatively affect our immune system by developing hypersensitivity to their active ingredients.”