papaya diet

Today is week 2 of Tlakaelel's fruit fast diet. I am doing papaya. I could not find the papayas at Stop and Shop, so I bought a bottle of mandarin-papaya-mango juice. Probably not exactly what the Maestro meant, but there was no bottle or concentrate of papaya only.
Actually it's yummy juice, but it's all sugar. Is it better to drink healthy juice filled with sugar and calories or diet caffeine-free pepsi with no calories (or nutrition)?? Hmm??