The YMCA was speaking after new rules to outlaw so-called "legal highs" come into force in the UK on Thursday.
It means a blanket ban on the production, distribution and supply of psychoactive substances.
Liam Preston from the YMCA told Premier's News Hour the ban "doesn't go far enough."
He said: "I think the ban will go some way to reducing usage, and that's certainty what our research has found, but actually we don't think it's gone far enough in tackling the harm that young people are going to face."
"The real dangers around it, they're not tackled at all by this ban."
The YMCA released research ahead of the ban which showed most young people will ignore the ban.
Six in ten of those who've previously used legal highs say they will use them again.
YMCA Survey:
- Of those young people who currently take legal highs, 64% say they would be likely to use them in the future.
- 57% of respondents first started taking legal highs between the ages of 16 and 18-years-old.
- Of young people who have ever used legal highs, 94% have friends who have also used them.
- 68% of those who have taken legal highs name Laughing Gas as the substance they take most commonly
Mr Preston suggests young people don't understand the dangers.
"There are some highs that are perceived to have less damage done from them... laughing gas in one of them," he said.
"But our work and the conversations we've been having with young people - particularly around Spice - they're showing symptoms and signs akin to heroin."
He wants community organisations, including churches to have a role in preventing people using highs and should offer support.
Police now have the power to shut down shops selling legal highs - and there are tougher sentences of up to seven years for offenders.
Listen to Premier's Hannah Tooley speak to Liam Preston here: