Health Effects of Coffee & Tea
Coffee & Tea both contains caffeine, which speed up action of the nerves & increase level of Adrenaline in blood as a result heart rate, breathing rate, urinary output and production of stomach acids all go up.
A cup of coffee contains 275 mg of caffeine. Caffeine triggers the muscles to start using fat as an energy source rather than sugar. But caffeine has diuretic effect. Actually 300 mg caffeine (equilent to eight cups of coffee) in one sitting might have diuretic effect, but not if one drink this amount over a day. Caffeine also depletes calcium from body. Coffee reduces the risk of Colon cancer in woman by 50 %.
Tea & Coffee both contains tannins that bind brain-boasting nutrients iron by 75 %. So, limit coffee to three cups or less each day and drink your coffee or tea between the meals. Tannin present in tea helps to protect dental carries.
Tea helps fight against infections. It contains chemicals, which are also present in the some bacteria tumour cells, parasites and fungi. These chemicals are called Alkylamine antigens, which primes the response of an immune blood cell called gamma delta T cell. Actually T cell prompts the secretion of Interferon (a key part of bloods chemical defense system) against many types of bacterial, viral, fungal and parasitic infection.
Tea plant contain L- Theanine (A newly identified amino acid). L- theanine in small amounts is an antagonist to caffeine, means green tea drinker experience the positive effect of the caffeine. L-Theanine broken down in liver to ethylamine (alkylamine).
Tea is also a rich source of Flavonoids (antioxidants) which help fight against heart disease. Antioxidant as polyphenol in tea helps the body against damaging radicals. (A cup of tea contains half the antioxidant of orange juice.)
Major Types of tea: there are three main types of tea as
Black Tea: Harvested leaf withered & oxidized for several hours before firing halts the process.
Oolong Tea: Harvested leaf are oxidized but for not as long as black tea. It is in a sense “Intermediate between green & black. Tea produce from it is of pale jade green to pink to deep gold.
Green Tea: This tea is not oxidized at all, freshly harvested leaf are rolled & fired immediately. Tea produce from it is of Greenish-gold of colour.
Green tea Nutritional value:
University of San Francisco research shows that green tea contains polyphenols, which give bitter taste to it. Following are four polyphenols also known as Catechins found in green tea.
1. Epicatechin
2. Epicatechingallate
3. Epigallocatechin
4. Epigallocatechingallate (EGCg)
These polyphenols can boast availability of important brain boating substance Dopamine. Dopamine is involved in transmitting of the signals of rewards and motivation. These polyphenols also help to protect LDL cholesterol from oxidation in other words deposition of lipids, which are associated with heart disease (arteriosclerosis). According to study conducted in University of Shizouka, Japan later two are most important to protect oxidation of LDL.
Green tea extract may play a role in the control of body weight by affecting sympathoadrenal system which activate thermo genesis (excess caloric burning) a person using green tea extract utilize 266 extra calories and in its urine amount of Norepinepherine increased due to increase activities of sympathoadrenal system.
By
Shahid Hafeez Shahid,
M.Sc. (Hons)Food Technology, MS Total Quality Management.
Manager Quality Assurance and Product Development,
A’Safwah Dairy & Beverage, Subsidiary of DCF Co.(SAOG), Salalah Oman.