By A.S.

If a doctor or scientist says “there’s a lack of evidence for this” or “there’s no evidence for this”, they are conflating two very different situations:

1) “We have studied this extensively, and we have good evidence suggesting it doesn’t work / isn’t beneficial”

2) “There have been no (good) studies done on this yet, hence we lack evidence whether this works.”

For the doctor / scientist, saying “lack of evidence” is very easy because they don’t have to think whether they’re in situation 1 or 2. Whether they’re in situation 1 or 2, saying “lack of evidence” is always a medically / scientifically accurate statement to make.

However, policymakers and media interpret a doctor or scientist saying “lack of evidence” as meaning the first thing: “this has been extensively studied and we concluded it doesn’t work.”

This way, new and genuinely good ideas get squashed. Namely: it hasn’t been studied yet => a doctor or scientist says “lack of evidence” => everyone falsely interprets that as meaning “it has been extensively studied and it doesn’t work” => the idea is seen as “disproven” rather than “non-studied”.

On top of this, scientists aren’t incentivized for studying unconventional ideas that very well might not work. They probably don’t get money or respect for doing that.