High Octane Tea: Benefits, Side Effects, and Preparations

High Octane Tea

Verywell / Alexandra Shytsman 

High Octane Tea is a beverage made by Zest Tea company. It is advertised to be the most caffeinated tea on the market. The tea is popular as a coffee alternative for those who are trying to find a way to boost energy throughout the day. Fans of the drink say High Octane Tea provides stimulation without the jitters. The popularity of the drink has led some to try to make their own versions at home.

What Is High Octane Tea?

Zest Tea is a Baltimore-based company started by James Fayal and Rickey Ishida. The co-founders created an extra-caffeinated tea after becoming increasingly frustrated with poor quality office coffee. They developed a blend and then used a crowdfunding platform to bring the product to market in early 2014. The company now makes several products including CBD tea, several varieties of loose leaf high-caffeine tea, sparkling teas, and a variety of flavors of the popular High Octane Tea.

The company's founders attribute the effect of High Octane Tea to its combination of caffeine and L-theanine, an amino acid present almost exclusively in the tea plant. L-theanine can also be found in some mushrooms and is known to contribute to the umami taste and unique flavor of green tea.

According to the company's website, the combination of the amino acid along with caffeine allows the tea to provide a jolt of stimulation without the jitteriness often attributed to excess coffee consumption. Zest Tea refers to the effect as "calm energy," and cites a 2008 scientific study to support this claim.

Types of Tea

High Octane Tea comes in six flavors, each with a different base and combination of ingredients. The teas are non-GMO, gluten-free, and contain low to no sugar. Flavors include:

  • Blue Lady: South Indian flower orange pekoe black tea, cornflower petals, hibiscus flowers, orange peel, lemon, orange, and passion fruit flavor
  • Cinnamon Apple: South Indian flower orange pekoe black tea, cinnamon chips, apple pieces, cinnamon flavor, and apple flavor
  • Earl Grey: South Indian flower orange pekoe black tea and bergamot flavor
  • Pomegranate Mojito: Young Hyson Chinese green tea, peppermint, pomegranate, and lime flavor
  • Spicy Masala Chai: Flowery orange pekoe black tea, tea extract, cardamom seeds, ginger root, cinnamon chips, natural flavor, and cloves
  • Superberry Samba: Young hyson Chinese green tea, tea extract, natural passionfruit flavor, safflower petals, natural strawberry flavor, and natural açai flavor

You can purchase the teas online or through select retails stores around the country.

How to Prepare High Octane Tea

You'll prepare High Octane Tea just as you would prepare any traditional tea. Use filtered water if possible and a temperature-controlled teapot to regulate water heat.

5 Steps to Prepare High Octane Tea

  1. Place one pyramid tea bag in an 8-ounce teacup.
  2. Heat water to 90-95º Celsius or 194-205º Fahrenheit. If you don't have a temperature-controlled teapot, bring water to a boil and then let sit for a minute to reduce the temperature just slightly. 
  3. Pour eight ounces of water over the teabag.
  4. Let tea leaves steep for as long as desired. Some drinkers prefer a lighter tea, so a two-minute steep is sufficient. A 3-5 minute steep will brew a stronger darker cup of tea, although steeping too long may introduce bitterness. As a general rule, green teas need less time while black teas need more time.
  5. Remove the tea bag or infuser or strain loose leaves from the cup before drinking.

Zest Tea company also suggests that their products make good iced tea. You can either prepare hot tea, let it cool slightly, then pour the tea over ice. Or you can prepare overnight iced tea by placing six tea bags in a pitcher with four cups of water and letting it sit overnight.

There are some online reports of people trying to make their own homemade version of high octane tea. Recipes vary slightly, but most often the tea is made from black tea, cardamom, cinnamon, milk, and a pinch of coffee.

Caffeine Content

According to the company, Zest's High Octane Tea contains about the same amount of caffeine in three regular cups of tea. The caffeine content of tea can vary, however. An 8-ounce cup of regular green tea may contain about 30mg of caffeine, while a cup of black tea may contain closer to 50mg.

The company also states that their tea contains about the same amount of caffeine as a cup of coffee. One eight-ounce cup of brewed coffee is likely to contain about 95–125mg of caffeine. But depending on the flavor that you buy, you'll get 135–150mg of caffeine in High Octane Tea.

Since the company advertises the amount of L-theanine in their High Octane Tea, it can be helpful to examine the amount in typical types of tea compared to Zest's products. According to their website, each variety of the High Octane tea provides 40mg of L-theanine.

A 2016 study acknowledged a substantial variation in levels of L-theanine found in different tea types and that processing can play a role. Research has shown that of all commercial teas, black tea provides the highest concentration of L-theanine with green tea providing much less. Some black teas were shown to provide up to 30mg of the amino acid per cup, while the average cup of green tea contains only 12mg or less. A typical tea bag is likely to contain about two grams of dried tea.

Health Benefits

Many studies have investigated the benefits of tea in general. Research has also explored the potential health benefits of combining L-theanine and caffeine.

Caffeine and L-Theanine

The study cited by Zest Tea co-founders as evidence of their product's effectiveness was published in The Journal of Nutrition in 2008. It examined the effects of L-theanine (100mg) and caffeine (50mg) on human cognition and task performance. The results of the study suggested that the combination of the amino acid and caffeine improved cognitive performance in study participants.

It should be noted that the study was small in scope (16 participants aged 21 to 40) and funded by a grant provided by the Lipton Institute of Tea in association with Unilever Beverages. However, more recent research has supported the 2008 findings to some degree, although the sample size was small in many of the studies.

For instance, a 2010 study involving 44 young adults showed that a combination of caffeine (40mg) and L-theanine (97mg) helped study participants improve accuracy during task switching, improved self-reported alertness, and reduced self-reported tiredness. But the study indicated there was no significant improvement in other cognitive tasks such as visual search, choice reaction times, or mental rotation.

Another study published in 2012 involved 16 participants and compared L-theanine to caffeine. Researchers found that the amino acid was able to reduce anxiety and improve blood-pressure in their subjects who were high-stress-response adults.

Lastly, a 2020 study found that a combination of L-theanine and caffeine improved sustained attention and overall cognitive performance in six children with ADHD. Researchers indicated the benefit was most likely due to decreased mind wandering during attentive periods.

General Benefits of Tea

One of the most likely benefits that you are likely to experience from most types of tea is a boost in energy and an increase in mental alertness from the caffeine. Herbal teas do not contain caffeine, so you are not likely to get this benefit from consuming teas like chamomile or hibiscus tea.

Drinking tea may also provide other benefits. For example, the consumption of tea has been linked to a reduced risk of cancer, including skin, prostate, lung, and breast cancer in humans. Ongoing research is investigating the relationship. However, the National Cancer Institute maintains that while there is a possibility tea consumption offers cancer prevention properties, results have been inconclusive and more research is still needed.

The consumption of tea is increasingly being shown to be associated with enhanced cardiovascular and metabolic health. There is some evidence that green tea may enhance lipid metabolism, prevent the appearance of atherosclerotic plaque, and other cardiovascular benefits. And some evidence shows that long-term consumption of black tea results in the improvement of blood pressure and may also reduce the risk for stroke.

In addition, black tea contains polyphenols including catechins, flavonoids, and tannins. Polyphenols are plant-based chemicals that may provide health benefits. Research has linked the consumption of flavonoids to important health outcomes due to their anti-inflammatory, anti-oxidative, anti-mutagenic, and anti-carcinogenic properties. But health experts advise that more research is still needed to say for certain if black tea can significantly boost your health.

Side Effects

Consuming any beverage with caffeine can produce side effects in some people. These may include increased heartbeat (tachycardia), palpitations, restlessness, nervousness, problems with sleep, or a headache. Some people may even experience nausea, vomiting, diarrhea, and diuresis (or frequent urination).

A 2017 study funded by the National Institutes of Health, however, states there is little evidence of health risks associated with moderate amounts of caffeine in healthy adults. Moderate consumption of caffeine is defined as about 300 to 400 mg per day.

There is some concern that those who take sedatives should avoid L-theanine. The Memorial Sloan Kettering Cancer Center advises that women who are pregnant or breastfeeding or those who are hypersensitive to green tea should avoid L-theanine as well.

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Verywell Fit uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Malia Frey, M.A., ACE-CHC, CPT
 Malia Frey is a weight loss expert, certified health coach, weight management specialist, personal trainer​, and fitness nutrition specialist.