Hi Bec - this is my latest post: https://steemit.com/diet/@dwarrilow2002/better-dietary-options-from-canadian-study
A cleanse is good, if what you are cleaning needs to be cleaned. A person who is being starved doesn't need to be cleansed ... they need to be fed. Cleansing in that case is like bleeding used to be.

Picture a barn with a bunch of rotting boards. Cleansing these boards would be good but it would be better to replace those boards with new boards would be better. Take as an example Vitamin B12.

Vitamin B12 is found only in animal foods and fortified foods. People who avoid all animal products should look for meat alternatives, such as soy products fortified with vitamin B12.
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However I disagree with this because of the following:

Soy can cause some mild side effects such as constipation, bloating, and nausea. It can also cause allergic reactions involving rash and itching in some people.
Long-term use of high doses of soy dietary supplements is POSSIBLY UNSAFE. There is concern that taking high doses might cause abnormal tissue growth in the uterus. ...
Breast cancer: The effects of soy in people with breast cancer are unclear. Some research finds that soy might “feed” certain breast cancers because it can act like estrogen. Other studies have found that soy seems to protect against breast cancer. The difference in effects might have something to do with the amount taken. Because there isn’t enough reliable information about the effects of soy in women with breast cancer, a history of breast cancer, or a family history of breast cancer, it’s best to avoid using soy until more is known.
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Having a 3-4 eggs per day or eating a quantity of fish would be a better option than taking in soy.