Tea to give us energy and improve our focus

One of the most controversial components of our tea is caffeine, which is found in more than 60 plants (known to date). It is called caffeine because Friedrich Ferdinand Runge discovered it in 1819 in coffee, hence its name.

It is interesting to know that this alkaloid is part of the methylxanthine family (alkaloids that stimulate the central nervous system), which also includes theophylline (present in black tea) and theobromine (present in cocoa), although they are all from the same family, they "affect" us in different ways.

Caffeine

It's easily absorbed because the molecule is "free" and enters our bloodstream quickly and effectively, which is why a strong coffee wakes us up so quickly. It has a longer half-life than theophylline. It's addictive, increases alertness and emotional stress, and stimulates the nervous system more than theobromine. It can also relieve short-term fatigue or drowsiness, but once its effect wears off, you experience a crash.

The caffeine in tea is bound to other compounds, which causes it to enter our bloodstream and reach our brain more slowly, in small amounts; we call this theine. I'll explain this in more detail later.

Theobromine

It's a mild stimulant, similar to caffeine, but it's also a vasodilator that lowers blood pressure. It's found in cocoa beans, kola nuts, and tea.

Theophylline

It is used to prevent and treat wheezing, which are those high-pitched, whistling sounds produced when breathing, caused by the narrowing or blockage of the airways in the lungs, shortness of breath, and chest tightness caused by lung diseases such as asthma, chronic bronchitis, and emphysema. This alkaloid relaxes and opens the airways in the lungs, making breathing easier.

As I mentioned before, although tea contains theine, its effect on the brain is different from when we consume caffeinated drinks, since it also contains a substance called L-theanine that makes our body absorb the stimulant more slowly and has a relaxing effect (opposite to caffeine).

L-theanine

Tea is the only food that contains it naturally; it's a psychoactive amino acid that reduces stress, promotes relaxation, and improves memory and learning ability. Recent studies have found that it promotes the generation of alpha waves in our brain, the waves we produce when we are in a relaxed, alert, and tension-free state, typical of meditation.

This amino acid also increases the production of gamma-aminobutyric acid (GABA) and affects the levels of two neurotransmitters responsible for improving memory and learning: dopamine and serotonin. Studies have been conducted on how this "stimulant-relaxant" combination affects our brain, and the results are astonishing:

• The combination of L-theanine and caffeine significantly improved task-switching accuracy and alertness, and also reduced fatigue; the combination helps focus attention during a demanding cognitive task. (1)
• The combination of L-theanine and caffeine in a beverage led to faster reaction times in memory, numerical accuracy, and sentence verification. It also improved word recognition time. (2)

Tea to lose weight and/or maintain a healthy weight

On the other hand, the combination of caffeine and catechins (antioxidants in tea) helps to lose or maintain a healthy weight, as demonstrated by the following studies:

1. Green tea, caffeine, and catechins for weight management: These ingredients can increase energy expenditure and have been proposed to counteract the decrease in metabolic rate that occurs during weight loss. Positive effects on body weight management have been demonstrated using green tea blends. Green tea, containing tea catechins and caffeine, may act by inhibiting catechol-O-methyltransferase and phosphodiesterase. These mechanisms may also work synergistically. A blend of green tea and caffeine improves weight maintenance through thermogenesis, fat oxidation, and the preservation of fat-free mass. The sympathetic nervous system is involved in the regulation of lipolysis, and sympathetic innervation of white adipose tissue may play an important role in the overall regulation of total body fat. Together, these functional ingredients have the potential to produce significant effects on metabolic targets such as thermogenesis and fat oxidation. (3)
2. Tea polyphenols have been proposed to counteract the decrease in metabolic rate that typically occurs during weight loss. Their effects may be particularly important during weight maintenance after weight loss. The thermogenic effect of CCRTs (caffeine- and catechin-rich teas) has the potential to produce significant effects on metabolic targets such as fat absorption and energy intake, possibly through their impact on the gut microbiota. (4)

Well, now you have two more very good reasons to drink at least three cups of tea a day. Remember to drink different colors of tea (with their different caffeine contents) depending on the time of day:

• Black tea and pu erh tea in the morning, due to their high theine content.
• Green tea and oolong tea in the afternoon both have a medium caffeine content.
• White tea at night has a low caffeine level (except for Yin Zhen white tea, which, being made with the buds of Camellia sinensis, has a high caffeine level because the plant concentrates the alkaloid that acts as a natural insecticide in the buds).
  
  

Olivia Medina
Tea Master, EURO TE

1. T. GIESBRECHT, AND JA RYCROFT, AND MJ ROWSON AND EA DE BRUIN (2013)
2. HASKELL CF, AND KENNEDY DO, AND MILNE AL, AND WESNES KA, AND SCHOLEY AB
3. MS WESTERTERP-PLANTENGA
4. RICK HURSEL AND MARGRIET S WESTERTERP-PLANTENGA