For those of you who have been surfing net for natural remedies for weight loss, you must have come across this one a million times. Green Tea!!!
And yes it breaks my heart apart to suggest that the not so palatable green tea helps with weight loss.
One of my colleagues was eager to try green tea for weight loss and she bought around a kilo or more of it since she got it at a pretty cheap rate.
But the eagerness was soon replaced by disappointment, because green tea is not one of those tasty energy stimulating drinks.
She struggled to finish the packets and moderately resolved the matter by adding jaggery to her tea.
Now I don’t really know if that added calories or did it eventually help with weight loss because she did not stick to it for long.
- It prevents development of fat cells.
- It inhibits fat formation and deposition.
- It increases fat oxidation (breakdown of fats by oxidation) and thermogenesis (production and utilisation of energy from food).
- Green tea promotes post meal satiety and suppresses hunger.
- Green tea is proven to help in weight reduction by modulating obesity related genes.
- It also regulates activity of hormones that favour fat deposition. Components present in green tea
- It improves antioxidant status and reduces cardiovascular risk which helps in weight loss.
Coming to the composition of green tea, it is a rich mixture of protein, carbohydrates, trace elements and vitamins. It is derived from the plant Camellia sinensis.
Other teas such as black tea and oolong tea are prepared by fermenting green tea.
Green tea is rich in a type of antioxidants called catechins.
There are four kinds of catechins mainly find in green tea: epicatechin, epigallocatechin, epicatechin-3-gallate, and epigallocatechingallate(EGCG).Green tea contains caffeine which is said to help in burning fat.
Most research work in relation to green tea and obesity has been conducted on the potential of these compounds to induce weight loss
How green tea helps in weight loss?
Here are some clinical trials that demonstrate the positive effects of green tea on weight loss and the mechanisms by which it acts.
1. Flavonoids in green tea help in weight loss
Green tea is rich in flavonoids- plant derived compounds that serve as antioxidants.
Catechins are a type of flavonoids found in green tea which prevent oxidative damage and prove to be therapeutic in case of cancer, heart diseases etc.
Individuals with obesity and metabolic syndrome were recruited for a study wherein they were given either green tea or green tea extract supplements.
Significant decrease in body weight and BMI was seen in both groups. Green tea beverage also brought about a decrease in cholesterol and blood lipids.
What it means: It was concluded that green tea flavonoids help in weight loss and in improving symptoms associated with metabolic syndrome.
2. Green tea helps burn calories and fats
One way in which green tea helps in reducing weight is by favouring immediate conversion of food into energy and supporting utilisation of the energy.
In this manner green tea prevents fat deposition. It is also known to support fat oxidation (breakdown of fats by oxygen).
Another mechanism by which green tea burns fats is by manipulating activity of enzymes. Catechins present in green tea inhibit catechol-o-methyltransferase.
This enzyme prevents breakdown of norepinephrine. Norepinephrine is a chemical secreted in response to stress. In presence of norepinephrine, green tea extract favours breakdown of fats present in fat cells.
Green tea not only enhances your metabolism while exercising but even when you are resting. Yes don’t be surprised, you require energy for essential body functions like brain function and breathing even while resting.
3. Green tea is good for high BP patients
As a part of the research study, obese hypertensive patients were supplemented daily with a capsule of green tea extract for 3 months.
Decrease in blood pressure, blood glucose, cholesterol was observed in green tea extract group. Reduction in inflammation and improvement in antioxidant status was noted.
What it means: Overall improvement in these metabolic parameters caused by green tea can aid in weight loss and improve health status of obese individuals.
4. Caffeine enhances weight loss outcomes of green tea
Green tea catechins in combination with caffeine which is present in green tea has a stronger effect on weight loss.
A review of 15 studies reports that consumption of green tea catechins with caffeine leads to significant reductions in weight, BMI and waist circumference. Green tea catechins alone are not found to be effective for weight loss.
Caffeine and other compounds present in green tea help with weight loss. Subjects were given supplements with different variation in concentration of ECGC and caffeine.
Caffeine with or without ECGC was effective in supporting fat oxidation. According to the study ECGC and caffeine can cause weight loss by breakdown of fats.
A research study was organized to determine whether there is link between body weight and habitual caffeine intake.
Individuals having a high caffeine intake had better weight loss outcomes than those having low caffeine intake.
What it means: Caffeine and other compounds in green tea mixture help consumers lose weight.
5. More catechins in your green tea, greater is the weight loss
The amount of catechins present in the green tea affects the weight loss outcomes.
An experimental study proving this point reported that consumption of two servings of extra high catechin green tea leads to a considerable decrease in body weight, body fat, waist circumference and abdominal fat.
Another study indicates that consumption of green tea containing 609.3 mg catechins can cause loss of visceral fat especially in the abdominal region.
However few researchers are not convinced about Green tea’s anti-obesity effect….
A review of 11 studies demonstrating the effect of green tea on body weight regulation helped to elucidate that catechins or ECGC-caffeine mixture helps attain humble weight goals and supports weight maintenance. \
Caffine intake and ethinicity may influence the effect of green tea on weight loss.
Another review study covering different clinical trials conducted on green tea and its effect on weight loss, reports that green tea preparations bring about a small and statistically non significant reduction in weight.
Also it was reported that green tea did not help with weight maintenance. Mild to moderate adverse events were reported.
Dietary supplementation of 300mg ECGC/day failed to enhance the effect of low calorie diet on weight loss and it also did not show any improvement in cardiovascular risk factors.
One clinical trial reported that long term consumption of green tea, and by long term they mean 12 weeks, had no effect on individual’s body weight, body fat and metabolism.
Disappointingly, results of this study seem contrary to green tea’s mechanism of action that has been proven in animal model.
Milk protein and green tea individually are known to help with weight loss by supporting utilisation of energy from food and preventing fat deposition. Oddly when taken together milk protein inhibits green tea’s efficiency in burning calories.
Why green tea induces immediate weight loss in clinical trials and not in real life?
An assessment of 14 clinical trials regarding green tea and its effect on obesity revealed a few interesting points:
- Green tea groups lost around 0.2- 3.5 kg over a period of 12 months. This change is not significant enough.
- Green tea used in the clinical trials was not actual tea preparation. They were either beverages rich in catechins and ECGC or supplements containing green tea extracts.
- A loss of 5 to 10% body weight was considered to be beneficial in reducing cardiovascular risk but actual values of weight loss were not significant.
So is there any way to enhance the weight loss effect of green tea?
Green tea when combined with other food items or techniques for weight loss can induce better weight loss outcomes.
Green tea & Inulin are good weight loss tools.
Inulin is a type of carbohydrate that is stored as a dietary fibre.
It is commonly isolated from root of chicory plant and is said to help with weight loss.
Research proves that consumption of green tea and inulin together can help reduce body fat and also be beneficial for weight maintenance.
Does green tea work as a meal replacement?
A novel green tea formula as a meal replacement was tested for its safety and efficacy.
An experimental group received green tea formula while control group received normal diet. Experimental group experienced great weight loss and reduced fat mass along with improvement in cholesterol levels.
However this is pertaining to a specific green tea formula; we do not intend to suggest replacing regular meals with green tea unless advised by a health practitioner.
Green Tea & vitamin E work synergistically as strong antioxidants
A clinical trial was organized to investigate the effect of green tea and vitamin E consumption as well as exercise on antioxidant and metabolic parameters. Vitamin E is a strong antioxidant.
Green tea and vitamin E combination led to increased serum Vitamin E levels and decrease in waist circumferences.
According to the study daily consumption of green tea and vitamin E can add to the benefits of exercising.
Green Tea improves exercise induced calorie burning and loss of belly fat.
It also increases muscle mass and muscle strength.
Beverages rich in green tea catechins improve exercise induced weight loss especially in terms of decrease in abdominal fat and blood lipid levels.
Novel green tea extract supplements that aid in weight loss
A novel botanical supplement comprising green tea, capsaicin and sweet pepper was evaluated for its efficacy.
Capsaicin is an active component of chillies that imparts the pungent irritating taste that helps in weight loss. Overall the bioactive ingredients were successful in perpetuating weight loss by promoting satiety, reducing appetite and reducing energy intake.
Tablets containing a novel green tea extract (GreenselectPhytosome) named MonoCam is proven to help in effective weight loss when combined with low calorie diet.
The experimental group lost around 14 kg of initial weight while group receiving only low calorie diet lost 5 kg.
Decrease in cholesterol and leptin levels was observed in the experimental group. Results suggested that MonoCam is safe and effective weight loss supplement.
What does this mean? Green tea can enhance weight loss outcomes when combined with a other weight loss techniques. Green tea and exercise is the best combo.
How much green tea should you drink to lose weight?
Green tea does not give you immediate weight loss results.
One reason for this could be that preparation of fresh green tea cannot successfully extra a good amount of catechins from the leaves.
Most of the studies covered by us report the consumption of 3-4 cups of green tea daily or consuming 300-400mg of green tea extract in a day.
University of Maryland Medical Center recommends consumption of 2-3 cups of green tea per day which would account for an intake of 240-320 mg polyphenols. In terms of green tea extract consumption of 100-750 mg per day is recommended.
Also the amount of caffeine present in the tea is of great importance. Upper limit for caffeine consumption is somewhere around 300-400mg. So caffeine and polyphenol content is a good way to evaluate the brand of green tea.
Precaution to be considered while consuming Green tea
Though it is a herb, green tea consumption can cause side effects due to drug interactions or allergies.
It is best to consult a physician before using green tea especially green tea supplements for weight loss.
Individuals suffering from liver or kidney problems, stomach ulcers or psychological problems especially anxiety should avoid green tea.
Caution should be exercised while consuming green tea if you suffer from anemia, diabetes, glaucoma or osteoporosis.
Caffeine overdose can lead to serious side effects. However green tea contains very low amounts of caffeine in comparison to coffee.
Equivocal scientific evidence is available in relation to green tea and weight loss.
Green tea causes mild weight loss and requires a considerable time period to act. Even average duration of clinical trials and research studies is around 3 months.
So if you are going to try green tea for a month and expect miracles that might not be the case.
Green tea consumption has numerous health benefits, so even if it doesn’t cause quick weight loss it can definitely help to improve overall health status and immunity.
Green tea when combined with exercise delivers the best results.
When taking up green tea as your main weight loss tool or consuming green tea extract supplements, do not forget to consult your health practitioner.