My personal opinion is that it is a judgment call. I know of nothing faster acting or cheaper, but I do not recommend taking more than is needed. This is usually no more than eight bottles over a period of two to three months. Taken in conjunction with definitively anti-cancer herbs, my experience is that TKG is safe. Vegetables that are high in chlorophyll, such as wheat grass, are also useful but much less fast acting than TKG .
Beets are also good as are lycium berries, little berries that can be eaten instead of raisins.
There are various barley green and similar powdered substances that supposedly improve oxygenation. Some of these seem completely flat and lacking both vitality and nutrients. For example, holy basil contains O7 and breaks down into seven oxygen molecules. Too much can be shocking to the system as die-off can occur faster than the body can rid itself of debris. This is not safe.