There's recently been a LOT in the news concerning green tea and weight loss.
Green tea is the least processed and thus provides the most antioxidant polyphenols, notably a catechin called epigallocatechin-3-gallate (EGCG), which is believed to be responsible for most of the health benefits linked to green tea.
Green tea's weight loss effects have been causing more and more people to start
drinking green tea

This article gives you the facts about drinking green tea to lose weight.

1) Green tea boosts your metabolism

A study reported on in the American Journal of Clinical Nutrition, found that green tea extract resulted in a significant increase in energy expenditure (a metabolism 'boost'). The researchers also concluded that that over a 24-hour period, green tea extract increases the metabolic rate by 4%. These effects are probably due to the high concentrations of catechin polyphenols found in green tea. These work to help intensify levels of fat oxidation and thermo genesis (the rate at which your body burns calories).

2) Green tea inhibits fat absorption and helps glucose regulation

Experts tell us that the catechus in green tea help to inhibit the movement of glucose into fat cells. Green tea may also act as al glucose regulator. It helps to slow the rise in blood sugar after a meal. This prevents high insulin spikes (lots of insulin promotes fat storage) and the subsequent fat storage.

3) Promotes Fat Loss

Green tea not only promotes fat loss, but specifically, the loss of visceral fat-fat that accumulates in the tissues lining the abdominal cavity and surrounding the intestines (viscera) and internal organs. Unlike fat deposits on the hips and thighs (which result in the so-called "pear" body shape), visceral fat (which produces the "apple" body shape) is highly associated with increased risk for metabolic syndrome and type 2 diabetes.

Green tea contains three major components that promote fat loss: catechins, caffeine and theanine. Studies suggest that green tea compounds promote fat loss by inhibiting both gastric and pancreatic lipase, the enzymes that digest triglycerides, and fatty acid synthetase, the enzyme responsible for synthesizing fatty acids into the form in which they can be stored in the body's adipose (fat) cells.

So there are ways that green tea can help you with weight loss... But, how much do
you actually have to drink to get these amazing metabolism boosting effects?
Experts vary, but the general consensus seems to be that 3 - 5 cups of green tea per day is optimal. Doing this can help you burn an extra 70 calories per day which amounts to 7 pounds per year. Pretty good for not exercising or cutting calories, right?
However, 3 - 5 cups can be a lot for some people, so you might also want to consider green tea extract, green tea pills or a green tea patch.

- A human study, published in the January 2005 issue of the American Journal of Clinical Nutrition, confirms green tea's ability to not only reduce body fat, but damage to LDL cholesterol as well. After 12 weeks of drinking just one bottle of green tea each day, 38 normal-to-overweight men in Tokyo had a significantly lower body weight, BMI, waist circumference, body fat mass and amount of subcutaneous fat compared to men given a bottle of oolong tea each day.
- After a 2 week diet run-in period, the men were divided into two groups, one of which drank a bottle of green tea containing 690 mg of catechins, while the other group drank a bottle of oolong tea containing 22 mg catechins. Not only did the men drinking green tea lose weight and fat, but the amount of their LDL cholesterol damaged by free radicals also dropped significantly. Since atherosclerotic plaques develop when cholesterol circulating in the bloodstream is damaged or oxidized, green tea's ability to prevent these oxidation reactions may explain some of its protective effects against cardiovascular diseases.

- Facts and cautions

1. Green tea is not a magic bullet

While some people will tell you that green tea is the be-all-end-all for weight loss success, I think the keyword here is balance. You're not going to eat 5000 calories a day, drink a cup of green tea and make it all go away - it just isn't going to happen. A healthy diet and increased exercise will go a long way in helping you lose weight and keep it off.

2. Be cautious of the caffeine if you have health problems

For some people that have heart troubles, high blood pressure or stimulant sensitivities, the caffeine in green tea may not be the best idea. If you're worried about the caffeine from green tea, try taking green tea extract. Most green tea extract is made from decaffeinated green tea so you can still get the weight loss benefits without the caffeine.
If you think the caffeine may be a problem, make sure to consult your doctor before starting green tea for weight loss. Also make sure to consult your doctor before starting green tea if you are pregnant or breastfeeding.

Bottom Line: Green tea helps you with weight loss by boosting your metabolic rate, regulating your blood sugar, suppressing your appetite and giving you something else besides that high calorie, high sugar coffee beverage to drink in the morning.
While it's not the magic bullet, it can definitely give you a boost in weight loss and in your overall health!

3. Limit Green Tea Consumption During the First Trimester of Pregnancy
Women are advised to take supplements of folic acid when trying to conceive and during the first trimester (the first 3 months) of pregnancy because it is during this time period that the baby's neural tube is developing. Folic acid helps ensure normal development and protects against spina bifida by enabling the production of the enzyme DHFR. While a cup or two of green tea is unlikely to pose a problem, drinking large amounts of green tea could decrease the activity of DHFR, increasing risk of neural tube defects.