Rosemary has a long history of culinary and aromatic uses and applications in traditional herbal and Ayurvedic medicine.
The rosemary bush (Rosmarinus officinalis) is native to South America and the Mediterranean region. It’s part of the Lamiaceae family of plants, along with mint, oregano, lemon balm, and basil.
Many people enjoy rosemary tea for its flavor, aroma, and health benefits.
Here are six potential health benefits and uses of rosemary tea, possible drug interactions and a recipe to make it.
1. Rosemary tea is high in antioxidant, antimicrobial, and anti-inflammatory compounds
Antioxidants are compounds that help protect your body from oxidative damage and inflammation, which can lead to chronic diseases like cancer, heart disease, and type 2 diabetes.
They can be found in various plant foods, such as fruits, vegetables, and herbs like rosemary. Rosemary tea also contains compounds that may have anti-inflammatory and antimicrobial properties.
Rosemary’s antioxidant and anti-inflammatory activity is largely attributed to its polyphenolic compounds like rosmarinic acid and carnosic acid.
Due to its antioxidant capability, rosmarinic acid is often used as a natural preservative to increase the shelf life of perishable foods.
The compounds in rosemary tea may also have antimicrobial properties, which may help fight infections. Rosemary leaves are employed in traditional medicine for their antibacterial and wound-healing effects.
Studies have also investigated the effects of rosmarinic and carnosic acid on cancer. They have found that the two acids may have antitumor properties and even slow the growth of leukemia, breast, and prostate cancer cells.
Summary: Rosemary tea contains compounds shown to have antioxidant, anti-inflammatory, and antimicrobial effects. The two most studied compounds in rosemary are rosmarinic acid and carnosic acid.
2. Rosemary tea may help lower your blood sugar
High blood sugar can damage your eyes, heart, kidneys, and nervous system when left untreated. Therefore, it’s critical that people who have diabetes properly manage their blood sugar levels.
Studies have shown that compounds in rosemary tea may lower blood sugar, suggesting that rosemary could have potential applications for managing high blood sugar among people with diabetes.
Though studies on rosemary tea specifically are lacking, test-tube and animal studies on rosemary itself indicate that carnosic acid and rosmarinic acid have insulin-like effects on blood sugar.
Some studies show these compounds can increase glucose absorption into muscle cells, lowering blood sugar.
Summary: Rosemary tea contains compounds that may help lower high blood sugar levels by exerting insulin-like effects and boosting glucose absorption into muscle cells.
3. Rosemary tea may improve your mood and memory
Experiencing stress and anxiety from time to time is common.
Though studies on rosemary tea specifically are lacking, evidence shows that drinking and inhaling compounds in rosemary tea may help boost your mood and improve your memory.
One study found that taking 500 mg of oral rosemary twice daily for 1 month significantly lowered anxiety levels and improved memory and sleep quality among college students, compared with a placebo.
Another 2-month study in 66 industrial employees noted that those who drank 2 teaspoons (4 grams) of rosemary in 2/3 cup (150 ml) of water daily reported feeling significantly less burnt out at their jobs than those who drank nothing.
Simply smelling rosemary appears to be beneficial. One study in 20 healthy young adults observed that inhaling rosemary aroma for 4–10 minutes before a mental test improved concentration, performance, and mood.
Moreover, a study in 20 healthy adults found that inhaling rosemary oil stimulated brain activity and improved mood. Participants’ activity level, blood pressure, heart rate, and breathing rate increased after inhaling the oil.
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Rosemary extract may improve mood by promoting a healthy balance of gut bacteria and reducing inflammation in the hippocampus, the part of your brain associated with emotions, learning, and memories.
Summary: Consuming and inhaling compounds in rosemary have been shown to reduce anxiety, boost mood, and improve concentration and memory. Smelling and drinking rosemary tea may offer these benefits, but more research is needed.
4. Rosemary tea may support brain health
Some test-tube and animal studies have found that compounds in rosemary tea may protect the health of your brain by preventing the death of brain cells.
Animal research suggests that rosemary may support recovery from conditions that can lead to brain damage, such as a stroke.
Other studies suggest that rosemary may prevent the negative effects of brain aging, even suggesting a protective effect against neurodegenerative diseases like Alzheimer’s.
Summary: Compounds in rosemary tea may protect the health of your brain — both from injury and impairment from aging and neurodegenerative diseases.
5. Rosemary tea may protect vision and eye health
While studies on rosemary tea and eye health are lacking, evidence suggests that certain compounds in the tea may benefit your eyes.
Animal studies have found that adding rosemary extract to other oral treatments can slow the progression of age-related eye diseases (AREDs).
One study examined the addition of rosemary extract to common treatments like zinc oxide and other AREDs antioxidant combinations, finding that it helped slow age-related macular degeneration (AMD), a common condition that affects vision.
Other animal and experimental studies indicate that the rosmarinic acid in rosemary delays the onset of cataracts — the gradual opaqueness of the eye that leads to blindness — and reduces the severity of cataracts.
Remember that most studies on rosemary and eye health have used concentrated extracts, making it difficult to determine what effect rosemary tea may have and how much you would need to drink to reap these benefits.
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Summary: Rosemary tea may contain compounds that can help protect your vision as you age by slowing the progression and severity of diseases like cataracts and age-related macular degeneration.
6. Other potential benefits and uses of rosemary tea
Rosemary has been studied for many other uses.
Other potential benefits of the compounds in rosemary tea include:
- May benefit heart health. One animal study found that rosemary extract reduced the risk of heart failure following a heart attack.
- May promote digestion. Rosemary extract is sometimes used to treat indigestion, but research is lacking. Still, rosemary supports digestion by promoting a healthy balance of gut bacteria and reducing inflammation.
- May boost weight loss. One animal study noted that rosemary prevented weight gain among rats, even those fed a high-fat diet.
- May promote hair growth. Some people claim that using homemade rosemary tea as a hair rinse promotes hair growth, but research is lacking. Some studies suggest that rosemary oil or extract can reduce hair loss but has to be applied to the scalp.
While these benefits seem promising, more research is needed to determine what benefits drinking rosemary tea may offer.
Summary: While the evidence is limited, rosemary tea may contain compounds that benefit your heart and digestive health, support weight loss, and even help treat hair loss. That said, more research is needed.
Potential drug interactions
As with many other herbs, some people may need caution when consuming rosemary tea due to its potential drug interactions.
Some of the medications with the highest risk of interacting negatively with rosemary tea include:
- anticoagulants, which are used to prevent blood clots by thinning your blood
- ACE inhibitors, which are used to treat high blood pressure
- diuretics, which help your body get rid of extra fluid by increasing urination
- lithium, which is used to treat manic depression and other mental health disorders
Rosemary can have effects similar to those of these medications, such as increasing urination, impairing blood clotting ability, and lowering blood pressure. If you take lithium, the diuretic effects of rosemary can lead to toxic levels of lithium accumulating in your body.
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If you’re taking any of these drugs — or other medications for similar purposes — it’s best to speak with your healthcare provider before adding rosemary tea to your diet.
Summary: Rosemary may exert effects similar to those of certain drugs used to treat high blood pressure, increase urination, and improve circulation. If you’re on medication, consult your healthcare provider before adding rosemary tea to your diet.
How to make rosemary tea
Rosemary tea is easy to make at home and only requires water and rosemary.
To make rosemary tea:
- Bring 10 ounces (295 ml) of water to a boil.
- Add one teaspoon of loose rosemary leaves to the hot water. Alternatively, place the leaves in a tea infuser and steep them for 5–10 minutes, depending on how flavorful you like your tea.
- Strain the rosemary leaves from the hot water using a mesh strainer with small holes, or remove them from the tea infuser. You can discard the used rosemary leaves.
- Pour your rosemary tea into a mug and enjoy. You can add a sweetener, such as sugar, honey, or agave syrup.
Summary: Making rosemary tea at home is an easy way to control its strength and content. You can brew a cup using only two ingredients and a stovetop or microwave.
Summary
Rosemary tea offers some impressive potential health benefits.
Drinking the tea — or even simply inhaling its aroma — may benefit your mood, brain, and eye health. It may also help prevent oxidative damage, leading to numerous chronic diseases.
However, it’s important to know its potential interactions with certain medications.
Rosemary tea can easily be made at home using only two ingredients and fits well into a healthy and balanced diet.
Many studies discussed rosemary extract and essential oils, so it’s hard to know whether rosemary tea will offer the same health benefits.
