It's not true. They're both bad, but football has higher rates of concussion. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2140075/

In addition to concussions, football players are also believed to receive repeated microtrauma from running into each other repeatedly.

It's a start but USSoccer limits heading up to age 13:http://www.ussoccer.com/about/recognize-to-recover/concussio...

"Eliminating heading for children 10 and under

Limiting the amount of heading in practice for children between the ages of 11 and 13"

This is an easy step that soccer has taken to reduce the occurrences of brain injuries. Anyone who is confused on this issue should note that any jostling of the brain can cause minor, short-term brain damage. It's bad enough to bounce a relatively soft soccer ball off your head to warrant removing the practice from the sport, especially for younger players.

Other sports, like football, present a much harder challenge. Even if you remove direct head contact as a variable, most aspects of tackling can result in concussions. The reason football is uniquely controversial is that minor concussions are mostly inevitable and severe concussions are commonplace.

By contrast, the most likely way to get a concussion in soccer is to head the ball, which isn't fundamental to gameplay. In any sport, you might run into another player at high speed but that's not typically a core part of the gameplay. Football is controversial because it's hard to fix.

using your head to hit the ball, and/or getting kicked in the head. ;)

FWIW, though, I've not heard that point either.

The possibility of concussions is present in [nearly?] every sport. Typically, head injuries are not a core part of gameplay. In the case of soccer, there have been concerted efforts to remove "heading" from practice and from games. Football is being targeted because minor/severe concussions are commonplace and result from a core aspect of the game.

> The possibility of concussions is present in [nearly?] every sport

Tennis, golf, swimming, weightlifting, etc - probably have a pretty low incidence of concussion. Stuff with teams and fast movement are probably most suspect; hockey and football would intuitively seem like the worst offenders.