Blue Tea: Benefits, Side Effects, and How To Make It

Blue tea — often called butterfly pea or blue pea tea — is an herbal infusion originating from South Asia.

It’s prepared by steeping the dried petals of Clitoria ternatea L., a plant notable for its vivid blue hue.

Beyond its use as a natural coloring agent, blue tea is commonly consumed for its health-promoting properties. For example, it’s been linked to improved cardiovascular and cognitive health and may offer anti-diabetic and anti-cancer benefits.

This article examines blue tea, covering its potential advantages, possible drawbacks, and simple preparation methods.

What is blue tea?

Blue tea is an herbal infusion made from the dried petals of Clitoria ternatea L., commonly referred to as butterfly pea. People often flavor the infusion with additions like mint, ginger, lemongrass, or cinnamon.

Butterfly pea blossoms can vary from white to deep blue. Their intense blue coloration is due to a high concentration of anthocyanins — antioxidant pigments also present in other blue and purple produce.

When brewed, the tea’s color can shift to red, violet, or green depending on the beverage’s pH or acidity. You can alter this by adding tonic water, lemon, or lime.

Besides imparting the signature blue tint, anthocyanins are credited with many of the tea’s purported therapeutic properties. Historically, butterfly pea has been used in Ayurvedic remedies for various conditions.

It’s also worth noting that butterfly pea flowers are used worldwide both as a natural dye in foods and as ornamental blooms.

Summary

Blue tea is an herbal infusion produced from butterfly pea flowers, which are rich in anthocyanins. These compounds provide the tea’s vivid blue shade and many of its claimed health benefits.

Benefits of drinking blue tea

Below are some of the more widely reported and research-supported benefits associated with blue tea.

High in antioxidants

Antioxidants are compounds that neutralize free radicals. Elevated levels of free radicals can cause oxidative stress, contributing to the development of certain illnesses (,).

As noted, butterfly pea flowers contain abundant anthocyanins — particularly delphinidin — which largely account for the blue to purple coloration (,).

Anthocyanins are a class of antioxidants found in edible fruits, vegetables, and flowers, and they have been associated with protective effects against conditions like heart disease, diabetes, and some cancers.

Research also indicates that delphinidin may guard against lipid peroxidation — a process that harms cell membranes, promotes aging, and leads to the formation of a carcinogenic byproduct called malondialdehyde (MDA).

Additionally, a small trial involving 16 overweight or obese men reported that taking butterfly pea flower extract after a fatty meal helped preserve Glutathione peroxidase (Gpx) levels. Gpx is an antioxidant enzyme that reduces lipid peroxidation.

Supports heart health

Consuming blue tea may support cardiovascular health by aiding blood pressure and cholesterol control.

Animal studies suggest butterfly pea flower extract can lower blood pressure through vasorelaxation — relaxing and widening blood vessels to improve circulation.

It also appears to have antithrombotic effects, meaning it may help reduce blood clot formation, a risk factor for stroke.

The small study of 16 men with overweight or obesity also found that consuming butterfly pea extract after a fatty meal reduced fat cell formation and triglyceride accumulation.

This suggests the extract may blunt the post-meal spike in blood lipids — a predictor of cardiovascular disease.

Researchers propose that this effect may be due to antioxidants in the flower inhibiting pancreatic lipase, the enzyme responsible for breaking down dietary fats.

May help regulate blood sugar

Anthocyanins in blue tea could aid blood sugar control.

Some studies indicate antioxidants in butterfly pea extract can inhibit carbohydrate-digesting enzymes such as intestinal alpha-glucosidase, pancreatic alpha-amylase, and intestinal sucrase.

By blocking these enzymes, the extract delays carbohydrate digestion and absorption, which in turn reduces post-meal blood glucose and insulin spikes (,).

Lower insulin levels have been linked to reduced risk of insulin resistance, vascular dysfunction, obesity, and metabolic syndrome.

However, evidence in humans is inconsistent regarding blue tea’s anti-diabetic effects.

One study in 15 healthy adults showed that consuming sucrose with 1 or 2 grams of butterfly pea extract lowered blood glucose and insulin levels 30 minutes later, suggesting improved post-meal glucose handling.

Conversely, the small trial in 16 overweight or obese men found no notable changes in blood sugar after a fatty meal supplemented with the same quantity of butterfly pea extract.

Also note that human trials have used concentrated flower extracts rather than brewed tea; brewed tea is much more dilute and likely won’t produce the same pronounced effects.

Other potential benefits

Additional possible advantages of drinking blue tea include:

• Anti-fungal and antimicrobial activity. Some antioxidants in the flower may offer antifungal effects against Penicillium expansum conidia and antibacterial activity against Streptococcus mutans and Staphylococcus aureus (, , , 10, 11).
• Enhanced brain health. Animal research suggests butterfly pea extract may boost memory and help prevent further cognitive decline in Alzheimer’s models, though human evidence is lacking.
• Caffeine-free option. Because blue tea is derived from butterfly pea flowers rather than the Camellia sinensis plant (the source of caffeine in traditional teas), it’s naturally caffeine-free.
• Natural blue dye. The vivid color of butterfly pea flowers is a favored natural alternative to synthetic blue food dyes, which have raised health concerns for some consumers.

Although research on blue tea’s benefits is promising, most studies focus on concentrated extracts and isolated antioxidants rather than the brewed beverage. Furthermore, human data are sparse, with much of the evidence coming from test-tube and animal experiments.

Therefore, more clinical research in humans is needed to better understand the health effects of drinking blue tea.

Summary

Because it’s rich in anthocyanins, blue tea may support heart and brain health and possess anti-diabetic, anti-cancer, and antimicrobial properties. Still, additional human studies are required to confirm these claims.

Potential side effects

At present, there are no well-documented adverse effects from drinking blue tea.

That said, anecdotal reports indicate that consuming large amounts might cause nausea, abdominal discomfort, or diarrhea in some people.

Summary

When taken in moderation, blue tea is generally regarded as safe.

How to make blue tea

Preparing a cup of blue tea is straightforward, and you can enjoy it hot or iced.

These are the basic ingredients you’ll need to brew blue tea at home:

• 1 cup (240 mL) boiling water
• 3–5 butterfly pea flowers, 1 tsp dried butterfly pea flowers, or 1 tea bag
• sugar, honey, or another sweetener (optional)
• juice from half a lemon or lime (optional)

Put the butterfly pea flowers or tea bag into a cup and pour in the boiling water. Let steep for about 5 minutes or until the water turns a vibrant blue. Sweeten to taste with sugar or honey if you like.

You can add lemon or lime juice, which not only provides a tart flavor but also lowers the tea’s pH and changes its color from blue to violet.

To make a cooling iced blue tea, let the brewed tea chill, pour it into a glass, and add crushed ice.

Summary

Brew blue tea by steeping butterfly pea flowers in boiling water. Add citrus for flavor and to alter the tea’s color.

The bottom line

Blue tea is an herbal infusion created by steeping butterfly pea flowers in hot water.

Its abundant anthocyanins give the tea its striking blue color and are linked to potential health benefits such as improved cardiovascular and cognitive health, and possible anti-diabetic and anti-cancer effects.

Blue tea is typically safe to drink, although excessive consumption may cause digestive upset in some individuals.

Next time you want a warm cup of tea or a chilled beverage, consider trying blue tea.