Changing lifestyle and poor dietary habits of people often lead to development of various maladies like obesity, diabetes, dyslipidemia and immune dysfunction. Obesity is now well-known as one of the global concerns because it is not only prevalent in the developed nations but also becoming common in the developing world with associated physiological threats. Dyslipidemia is more frequent in obese people with raised levels of LDL, triglycerides and cholesterol. Among contributory factors of obesity, dietary habits are considered one of reasons for its expansion. During the last few years, amplified consumption of carbohydrate and animal fat has contributed to increased incidence of atherosclerosis induced cardiovascular complications and diabetes mellitus. High cholesterol diet causes significant increase in serum cholesterol level along with sensitivity to oxidation. Sucrose rich diet induces hyper-triglyceridemia and hypercholesterolemia [1].

Phytochemicals are endemic in the human diet from the ancient times to fight against diseases as most of the medicines have been derived from plants. In the recent era, diet based therapy has been revitalized globally and people are adopting the approach of using natural materials as an intervention against various ailments. During the last few years, scientific investigations have proposed several modules like diet based regimen to prevent life threatening disorders including obesity, hypercholesterolemia and diabetes. Among these strategies, a promising tool is the use of functional/nutraceuticals foods that not only improve consumer health and wellness but also reduce disease risk with minimal cost. Green tea (Camellia sinensis) belonging to family Theaceae is one such example of functional drinks containing bioactive molecules holding cure against various diseases. Green tea contains appreciable amounts of phytochemicals especially catechins [2]. According to literature, dried tea leaves mainly contain 10–25% polyphenols mainly belonging to various classes i.e. flavonols and, flavonoids, and flavondiols. Green tea catechins are further comprised of different chemical moieties that inlcue epigallocatechin-3-gallate (EGCG), epicatechin (EC), epicatechin-3-gallate (ECG), epigallocatechin (EGC). Amongst these, EGCG is present in higher amounts and considered to be an effective antioxidant with appreciable radical scavenging abilities [3].

Owing to the prophylactic role of green tea, its consumption is escalating in the vulnerable segments to cope with health disorders thus besides being a traditional beverage acts as an intervention against various physiological threats. Keeping in view the lifestyle disorders, present project was designed to use locally grown green tea variety Qi-Men with special reference to its active ingredient namely catechins. Concurrently, functional drinks containing the health ingredients i.e. catechins and EGCG were the limelight of the present research investigation. The therapeutic role of functional drinks was explored against lifestyle disorders.

In present exploration, less feed consumption due to functional drinks is supported by the work of Babu et al. [11]. Results for drink consumption are similar to work of Yang et al. [12]. However, Lee et al. [13] elucidated suppressed fluid intake in a group provided EGCG solution. The differences may be due to the fact that they used EGCG solution without toting up any additive. However, in the present case drinks were prepared by adding flavor and artificial sweetener that may be a reason for improved consumption.

The current results showing reduced body weight gain in groups consuming drinks containing catechins or EGCG are in consistent with the study of Basu et al. [14] and Byun et al. [15] Weight reduction by green tea might be due to reduced digestibility and an increase in energy expenditure and fat oxidation through β-adrenoceptor activated thermogenesis of brown adipose tissue [16,17]. Inhibited lipid absorption from meals might be other reason for reduced weight gain [18].

Results for decreased cholesterol and LDL levels are in consistent with the work of Kim et al. [19]. Hypocholesterolemic potential of catechins can be accredited to increased fecal excretion of cholesterol and bile acid [20]. Tea catechins increase the bile acid excretion by preventing reabsorption from small intestine through disruption of micelle formation of bile acid. This increased excretion of bile acid and cholesterol activates cholesterol 7α-hydroxylase that enhances the conversion of liver cholesterol to bile acid to restock this loss thus resulting in cholesterol reduction. This decrease in hepatic cholesterol content in turn stimulates LDL receptor expression and lowers blood cholesterol level [21].

Results for non-significant effect of drinks on HDL are in agreement with previous work of Gomikawa et al. [22]. The effects could be due to presence of various bioactive components present in green tea [4]. Roghani and Baluchnejadmojarad [23] noted LDL reduction in diabetic rat modeling with EGCG. The proposed mechanism of LDL reduction by green tea catechins is through inhibition of cholesterol synthesis and dietary cholesterol absorption [24]. Crude catechins decrease plasma cholesterol concentrations by upregulating LDL receptor. The increase in the LDL receptor improves the uptake of low density lipoprotein cholesterol from the blood circulation [25]. Moreover, reduced expression of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGR) might be another reason for hypocholesterolemic activity of green tea as green tea EGCG also inhibits HMGR activity [26,27].

Low concentration of triglycerides by green tea might result from suppressed expression of stearoyl-CoA desaturase (SCD 1) gene. Because in liver triglyceride synthesis depends on the expression of the SCD 1 gene, that is involved in biosynthesis of oleate and palmitoleate, the major monounsaturated fatty acids of triglycerides. However, Watanabe et al. [28] is of the view that reduced activity of acetyl-Co A by green tea catechins is a reason for low triglycerides synthesis.

Reduced glucose level by green tea is supported by the work of Polychronopoulos et al. [29] that stated that there occurs inverse relation between green tea and blood glucose. The antihyperglycemic effect of green tea may be due to activated uptake of glucose, inhibited intestinal glucose transporter and decreased expression of gluconeogenesis controlling genes [30]. EGCG exhibits hypoglycemic potential by preventing the intestinal glucose absorption via sodium-dependent glucose transporter (SGLT1), lowering the expression of mRNA for gluconeogenesis controlling enzymes [31] and causing repression of glucose production, phosphoenolpyruvate carboxykinase (PEPCK) and glucose-6-phosphatase gene expression, hepatocyte nuclear factor 1α (HNF1α), and HNF4α in cells [32]. Additionally, EGCG has direct effect on hepatic glucose metabolism thus improving glucose stimulated insulin secretion [32]. Attenuation of insulin level with functional drinks in current exploration is supported by the work of Hsu et al. [33]. It is proposed that amelioration of insulin resistance by green tea is associated with increased expression of glucose transporter (GLUT) IV [34]. It can be concluded that green tea mitigates hypercholesterolemia and hyperglycemia effectually. It has cholesterol lowering properties along with hypoinsulinemic capability that could be associated with improved insulin sensitivity.

Our study demonstrates that drinks supplemented with catechins and EGCG are effective against obesity, hypercholesterolemia and hyperglycemia. Consumption of functional drink reduced the body weight. Functional drinks resulted in significant reduction in body weight that could be caused by a decreased feed intake. Moreover, improvement in lipid profile was observed in all trials but more pronounced in semi-diseased states i.e. trial-III and trial-II. Furthermore, serum glucose and insulin levels were also lowered significantly in the trial-III and IV. It was interesting to observe that catechins showed higher potency against hypercholesterolemia but EGCG reduced the hyperglycemia more effectively.