Drinking water can help you lose weight, whether you're restricting your calories or not. Consuming 2 cups of water before a meal helped a group of obese adults lose 2 pounds over a 12-week period without making any other changes to their usual intake, according to a 2015 clinical study published in Obesity.
How many tea bags should you use to make a half gallon of iced tea? One gallon is about 128 ounces, so if one tea bag is good for 10 oz  of water, then about 10 teabags is good for a gallon. Start with 10  and adjust accordingly with water.
Eight ounces of green tea contain about 35 mg of caffeine, which is about half the amount of caffeine found in regular, black tea. However, this is still more significant than decaf tea, which has between 2 to 10 mg of caffeine per cup. Even iced green tea has caffeine, about 15 mg in a 16 oz. container.