Conversation so far:
Did John Harvey Kellogg support drinking alcohol?
he felt that alcohol was a poison.
Why was he against alcohol?
Kellogg noticed deleterious effects that alcohol had on both the brain, the digestive system, and the liver, among other organs.
What other beverages was he against?
CANNOTANSWER.
How did he feel about coffee and tea hot chocolate?
Kellogg also opposed tea and coffee due to the caffeine content.
What did he feel was bad about using caffeine?
His view was that caffeine was a poison.
What was the popular view of alcohol at the time?
alcohol was a stimulant.
What research did he use to go against the popular view?
Kellogg's view was that "nature has supplied us with pure water.

Question: Did he work with any other professionals on his views?
Self-contained rewrite: Besides Kellogg, Did John Harvey Kellogg work with any other professionals on John Harvey Kellogg views?