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.
Put 4 to 8 tea bags into a clean 2 quart or gallon glass container (4 teabags for a 2 quart container, 8 tea bags for a gallon container). Fill with water and cap. Place outside where the sunlight can strike the container for about 3 to 5 hours. Move the container if necessary to keep it in the sun.