What are the possible side effects of Blueberry Tea?

Does blueberry tea have side effects?

We found no official source (NHS, FDA, NIH) that lists side effects of blueberry tea. What it does to you depends on what is in the bag, and products sold as blueberry tea are quite different.

What is in blueberry tea?

• Flavored black or green tea: tea leaves with blueberry flavor or dried berry pieces. These contain caffeine.
• Herbal or fruit tea: usually dried fruit pieces and other plant ingredients with no tea leaves, so normally no caffeine.
• Blueberry leaf tea: made from the leaves of the blueberry bush, not the fruit.

Read the ingredient list to see which one you have.

Caffeine in blueberry tea

If the base is black or green tea, it contains caffeine. Some people notice trouble sleeping, jitters or a faster heartbeat from too much caffeine. The NHS advises pregnant people not to have more than 200 mg of caffeine a day from all sources.

Is blueberry leaf tea safe?

A published 90-day study gave rats powdered rabbiteye blueberry leaf at up to 2,500 mg per kg of body weight a day and saw no deaths and no treatment-related behavioral changes. It did report a few minor, sporadic lab differences, and the authors suggested 2,500 mg/kg/day as a no-adverse-effect level. This was an animal study with powder, not brewed tea, and several endpoints were not tested, so it does not set an official safe amount for people.

Who should check first?

• Anyone pregnant or breastfeeding.
• Anyone taking prescription medicine, especially for diabetes or blood pressure, since we found no official interaction data for blueberry leaf. Ask a doctor or pharmacist.
• Anyone allergic to berries or to other ingredients in the blend.

Simple tips

Start with one cup, steep as the box says, and stop if you feel unwell. Choose products with a full ingredient list.

This is general information, not medical advice.