Introduction
Tea is one of the widely consumed beverages of all times. Amongst the black, white, and green tea types, the black tea accounts for three-quarter of the world’s tea consumption rate. Moreover, tea contains polyphenol substances and specifically catechins, which are antioxidants that are associated with many health benefits. Black tea is popular in the West, while green tea is highly consumed in the East (Ware par.24).
Similarly, the white and oolong tea forms are consumed the least according to the worlds’ tea consumption trends. Researchers have laid claims about the health benefits of tea with respect to its attributes and specifically the polyphenols, which are antioxidants and polychemicals. In the past, the majority of researchers dwelled on the common types of tea, viz. black and green, which are believed to contain higher percentages of the ingredients associated with health benefits than other forms. Evidently, tea has broad health benefits to consumers according to the available research. This paper will highlight the evidences to support the claim that tea can be used to prevent chronic diseases like cancer, heart diseases, and metabolic syndrome in respect to the researches conducted by different scholars.
Health benefits of tea consumption
According to a study by Ware, who is an associate professor, tea promotes health and helps in the prevention of chronic diseases (par.8). He further argues that several scientists base this claim on the polyphones components found in tea, which act as the main source of disease prevention. Some studies argue that some forms of tea assist in cancer, heart diseases, and diabetes prevention (Ware par.9).
Moreover, tea is considered to help in weight loss, through the breakdown of excess cholesterol and it keeps the mind alert. According to Thielecke and Bachmann, black tea increases the protective mechanisms in the body by reducing blood pressure and dangerous effects of fats in the arteries (25). The frequent and consistent consumption of tea reduces obesity by breaking down excess fats and it reduces the availability of type II diabetes, which is linked with the risk of coronary diseases. Ultimately, tea plays a very vital role in the body in the prevention of chronic diseases such as cancer, heart attack prevalence, and metabolic syndromes.
Role of tea in cancer prevention
Cancer has continued to be a threat to the modern society and this aspect requires the implementation of preventive measures. Cancer has the ability to multiply in the replication process limitlessly since the cells can grow fast (Kosuke and Nakachi 67). The green tea has polyphenols (antioxidants) that have free radical scavenging process, which prevents cells’ damage by cancer reactive oxygenated cells. According Carson and Riley, a certain study showed that men with prostate cancer who drank green tea experienced lesser tissue inflammation caused by the replication of cancer cells than those who do not take it (15). Furthermore, the study showed that the polyphenols could modify the inflammation of prostate cancer cells to prevent further replication (Carson and Riley 17).
Evidently, prostate cancer, which is common in the aged men, is comparatively lower in the Asian countries with high tea consumption rate than in the Western countries (Ware par.18). Prostate cancer is associated with inflammatory cells, which are controlled and contained by anti-inflammatory substances known as flavonoids in black tea. Flavonoids act as pathway signals to cells that counteract by reducing proliferation, and thus inducing apoptosis (Ware par. 27). Moreover, the body frequently secretes oxidants, which cause the friction of electrons that leads to the destruction of proteins and all genetic elements in the body. Consequently, the body is exposed to cancer prevalence. Fortunately, tea consumption helps to rectify such effects whereby the catechins, which are present in tea, inhibit several enzymatic activities that cause cancer.
Moreover, tea consumption assists in the protection against carcinogenic chemicals that causes skin cancer through polyphonic components. The prevention and treatment of cancer can be done through metastasis of skin cancer using green tea. According to Boon, Olatunde, and Zick, oral administration of green tea polyphenols can reduce the ultraviolet (UV), tumour growth, the multiplication, and the B-induced tumour conditions (19).
A research on this issue showed that individuals treated with UVB and given green tea polyphenols had reduced matrix metalloproteinase processes. The study further concluded that the administration of polyphonic constituents of green tea cause barriers to angiogenic conditions of cytotoxic T, which are cells necessary for tumour growth (Boon, Olatunde, and Zick 27). The research findings indicated that EGCG and ECG constituents, which are present in green tea, inhibit the adhesion process of melanoma cells found in upper human skin. Consequently, the prevalence of skin cancer can be reduced and treated through the polyphonic elements in green tea to reduce the UV concentration in the skin.
Furthermore, green tea apparently treats breast cancer using the EGCG, which is one of its constituents (Pisters et al. 124). A research conducted on the issue revealed that EGCG caused a decrease in ERK1/2 cell growth (Pisters et al. 124). In addition, research shows that EGCG could help in the reduction of breast cancer growth by inhibiting the replication of cells.
How tea contributes to weight and heart diseases reduction
Tea constituents such as flavonoids, kaempferol and myricetin are commonly associated with risk-reduction of heart attacks (Béliveau and Gingras 89). The main cause of the fatal coronary heart diseases is the heavy accumulation of high cholesterol in the blood. The main important “antioxidant in green is the EGCG, which plays an important role in boosting the rate of body metabolism and inhibiting the enzymes that break down the norepinephrine hormone” (Béliveau and Gingras 89). When this “hormone is inhibited, the norepinephrine levels increase, which is in turn, signals the break down of fat cells” (Béliveau and Gingras 89).
Therefore, the high availability of the norepinephrine hormone creates favourable conditions for the excess fat break down. Moreover, the EGCG continuously reduces the fat absorbed by the body at every meal intake. Consequently, it reduces the cholesterol level in the body, thus leading to weight loss with a healthy heart.
According to Ware, green tea is the healthiest among all other beverages that one can drink to reduce weight, boost the body metabolism processes, burn calories, and reduce calories in the body due to the vigorous thermogenic processes that it initiates in the body (par.12). Normally, the body usually converts both fat and sugar into triglyceride in the liver and ileum, which is transported to the entire body. The green tea has the capability to react to such body threats using the polyphenol content by activating the enzymes responsible for dissolving the triglyceride.
Furthermore, further studies show that in every commercial weight loss and fat burning supplement, a tea ingredient is present (Ware par.3). This assertion holds due to the ascertained claims that green tea increases the burning of fat during exercise. In an experiment, “men who drank green tea extracts during their exercise burned 17% more as compared to the other men who did not use the supplement” (Ware par.7). Moreover, another study revealed that green tea “increased fat burning rate during a vigorous exercise and rest” (Ware par.7).Several studies indicate that green tea makes the body burn more calories due to the presence of the EGCG constituent.
Interestingly, studies show that the use of “green tea can make the body burn more calories even at rest” (Kosuke and Nakachi 175). For instance, a person who is used to burning 200 calories per day, an increase of 3% was recorded amounting to 60-80 more calories burned than normal. In fact, in a study of 60 obese individuals, the group that drank green tea extracts burned 183 more calories and lost an average of 3.3 kg for 3 months (Kosuke and Nakachi 180). In addition, green tea has been identified to reduce appetite, thus leading to low intake of calories into the body. Conventionally, green tea has been identified in many weight loss and body-metabolism boost programs. However, some trends cannot be generalised to every person due to different body systems, environment, genetics, and size. Studies show that “green tea may reduce the levels of amyloid alpha protein, which is linked to heart diseases” (Kosuke and Nakachi 196).
Effects of tea on metabolic syndrome diseases
Metabolic syndrome is a condition “characterised by hypertension, disturbed glucose, insulin metabolism, and obesity” (Carson and Riley 65). Research by Carson and Riley indicates that metabolic syndrome leads to diabetes and obesity (65). Recently, studies conducted showed that green tea is linked to reducing risks of cardiovascular as well as weight loss. Metabolic diseases such as diabetes and obesity expose the body of an individual to many metabolic syndromes. Moreover, biochemical measurements portray that the EGCG present in green tea resists insulin and the availability of plasma cholesterol in the body (Carson and Riley 71). In addition, decreased liver weight and triglyceride content significantly decrease due to the intake of green tea. Many studies on green tea show that its extracts contain the EGCG anti-oxidant that helps to break down fat in the end.
A study conducted showed that the “EGCG combined with fish oil had significant effects in weight reduction, hence obesity reduction to individuals” (Ware par. 5). Studies conducted on obese people indicated that individuals taking green tea are likely to shed more weight as compared to their counterparts not taking the same (Ware par.5). The results from the study indicate that persistent and continued treatment with EGCG would decrease the risk of obesity conditions that come with metabolic syndromes. In addition, the combination of the EGCG with fish oil can significantly help to inhibit intestinal tumour genesis, hence a healthy body.
According to the “National Cancer Institute”, a study was conducted whereby scientists recruited 35 obese individuals with metabolic syndromes diseases (par. 5). The individuals were “grouped into three whereby the first group was given four cups of green tea per day, the second group received four cups of water with added two capsules of green tea, while the third group received four cups of water daily” (Muktar and Ahmad 1698). After a period of two months, the scientists noted that the two tea groups’ plasma antioxidant content and glutathione increased significantly (Muktar and Ahmad 1698). Nevertheless, there was no observable change that was noted on the level of caroteid and tocopherol in their blood. However, there was no observed change in the water group whatsoever (Muktar and Ahmad 1698).
Ultimately, the research provided novel evidence that green tea catechins control the antioxidant makers in the metabolic syndrome. Furthermore, it was evident that green tea manages the blood sugar levels in hypertensive individuals who consume it (BĂ©liveau and Gingras 123).
In addition, the levels of the LDL and HDL cholesterol improved more in the green tea group as compared to the water group. Moreover, the insulin glucose level (sugar level) improved after two months with green tea supplementation, but to the water group, nothing changed. Generally, the researchers concluded that the anti-inflammatory reaction of the green tea extracts gives a clear reason for the lowering of the blood pressure (BĂ©liveau and Gingras 135). Consequently, the cardio-protective effects and the general reduction in oxidative stress and the inflammation activity were due to the hypo-phonic constituents in the green tea extracts. Therefore, the researchers were in a better position to conclude that green tea extracts can reduce blood pressure, inflammatory biomarkers, and oxidative stress to improve conditions for insulin to resist obesity and hypertension in patients (BĂ©liveau and Gingras 139).
Counterclaims of the study
Even though tea has been claimed to prevent metabolic syndromes, heart diseases, and cancer, some facts have not yet been fully established. The study and tests on the individuals to provide substantial evidence on green tea benefits vary according to individual’s body size, environment, type of food, financial stability, and many other factors (Pisters et al. 127). Moreover, taking a lot of tea can be as well dangerous to one’s health. Drinking more tea can lead to more harm than the benefits therein. For instance, taking more tea causes dilation, which is the widening of the artery due to high blood pressure (Pisters et al. 130).
Furthermore, excessive tea consumption leads to allergies to some people. Therefore, it is very important to those individuals who experience such conditions to refrain from taking tea. In addition, polyphonic constituents, which are present in green tea, are believed to cause nutritional complications when taken in large amounts (Ware par.15). Despite preventing many diseases, tea consumption causes petulance, anxiety, and vomiting to some individuals. Since tea is a stimulant, “persons with asymmetrical heartbeats or anxiety attacks should take a serious caution when drinking it” (Ware par.17). For instance, breastfeeding mothers ought to take green tea in small amount like 2 cups daily. Unfortunately, amounts above this level can lead to miscarriage and several negative results to both the infant and the expectant mother (Ware par.18).
Several studies have been inconsistent, but some have been linked to reducing risks of breast, prostate, lung, and liver cancers (Thielecke and Boschman 135). The inconsistency of these results arises due to differences in methods of tea preparations and consumption, the type of tea environment studied, variation in genetics, and different responses to the people’s body mechanisms and other many varying lifestyle factors. Some studies did not find any reducing effects in cancer reduction in green tea (Thielecke and Boschman 140).
This aspect has created a heated debate towards the acceptance of the medicinal value of green tea due to differences in research findings by different scientists. Many researchers claim that the antioxidants in green tea have severe high blood pleasure effects if consumed unnecessarily, which many people do not take into considerations (Muktar and Ahmad 1699).
Almost all researches on the health benefits of tea have been left for the individuals’ decision. The green tea health benefits are still accompanied with serious side effects that leave researchers in a dilemma to recommend specific medical or dietary directions. Green tea has a flavonoid antioxidant that has many health rewards, but risks too (Boon, Olatunde and Zick 76). Flavonoids are said to bind the iron found in plants food such as vegetables. When tea is taken with such foods, it may deprive the body iron intake (Boon, Olatunde and Zick 85).
Moreover, green tea has some caffeine content that leads to nervousness, irregular heartbeats, and insomnia. Unfortunately, market tea contains high calories levels due to added sugar, which accounts to 50 calories per cup while others may even be higher. With all those extra calories coming from added sugar that has no nutritional value, it exposes the consumers to health risks unknowingly (Boon, Olatunde and Zick 96). In addition, tea causes teeth discolouring that only a few realise. Moreover, the research towards the risk reduction in cancer prevalence is inconclusive and yet to be determined.
According to the “National Cancer Institute”, most researches on this issue are not environmentally universal, and thus their results have great variance towards the conclusive cancer reduction effects by green tea (par. 7). Some researches do not factor in the difference in body sizes and the metabolism rate of each individual to standardise the results. Different studies conducted using the green tea extracts do not specify the concentration of the ingredients in the burning supplements. This aspect creates a discrepancy and methodology friction towards the sampling and testing of green tea. However, the concept of sugar content concentration is not clearly outlined in the research methods to cater for the blood sugar level watch (Muktar and Ahmad 1700). This misconception of information leads to study conflicts with respect to the differences in study methodologies. Ultimately, the general research process of each scientist seems to differ on the tea health benefits that culminate to instability and lack of confidence towards the cancer risk reduction in tea research.
Conclusion
Tea has many benefits, hence this paper supports the view that consumption of tea reduces the risk of cancer, weight gain, and heart diseases coupled with preventing and controlling metabolic syndrome diseases. From the studies conducted, research shows that tea has both positive and negative effects. However, the effects affect consumers differently depending on the tea type, the body size, the environment, the preparation method, tea concentration, and other factors. This paper supports the claims highlighted here since scientists have provided several evidences to support the same. With controlled and monitored intake, tea has more benefits than health risks. Even though conclusive recommendations have not yet been established to support the claims substantially, the scientific evidence supports the view that tea is highly beneficial to one’s health.
Works Cited
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Boon, Heather, Folashade Olatunde, and Suzanna Zick. “Trends in Complementary/ alternative Medicine Use by Breast Cancer Survivors: Comparing Survey Data from 1998 and 2005.” BMC Women’s Health 7.4(2009): 3-9. Print.
Carson, Christine, and Thomas Riley. “Non-antibiotic therapies for infectious diseases.” Antimicrobial Resistance in Australia 3.27 (2003): 144-147. Print.
Kosuke, Imai, and Kaikea Nakachi.” Cross study of effects of drinking green tea on cardiovascular and liver diseases.” British Medical Journal 310.6981(1995): 693-696. Print.
Muktar, Hasan, and Nihal Ahmad. Tea polyphenols: Prevention of Cancer and Optimising Health. The American Journal of Clinical Nutrition 71. 6 (2000): 1698-1702. Print.
National Cancer Institute: Tea and Cancer Prevention: Strengths and limits of Evidence. 2010. Web.
Thielecke, Frank, and Michael Boschmann. “The Potential Role of Green Tea Catechins in the Prevention of the Metabolic Syndrome – A Review.” Phytochemistry 70.1 (2009): 11-24. Print.
Pisters, Katherine, Robert Newman, Brenda Coldman, Dong Shin, Faldo Khuri, Waun Hong, Bonnie Glisson, and Jin Lee. “Phase I trial of oral green tea extract in adult patients with solid tumours.” Journal of Clinical Oncology 19.6(2001): 1830-8. Print.
Ware, Megan. Green Tea Health Benefits Examined 2014. Web.