Global Weight Loss Diet Market By Type (Meal Replacements, Low-calorie Sweeteners, Low-calorie Food, Organic Food, Diet Soft Drinks, Herbal Tea, and Slimming Water), By Application (Fitness Centers, Slimming Centers, Consulting Services, and Online Weight Loss Programs), By Region, and Key Companies - Industry Segment Outlook, Market Assessment, Competition Scenario, Trends and Forecast 2019-2028