American football

Is American football safe?

For staying alive, yes, mostly. For the brain, it is the most studied sport in the world, and the findings are uncomfortable. The National Center for Catastrophic Sport Injury Research (NCCSIR) at the University of North Carolina has counted football deaths since 1931. In 2025 it recorded 7 deaths during football activities across about 4.2 million US players at all levels, and none of them came from a collision. In high school, deaths from all causes averaged under 1 per 100,000 players a season in 2016–2023. With a season of roughly 60 to 70 practices and games, that works out at about 0.1 micromortsMicromortA one-in-a-million chance of death. It lets you compare the risk of very different activities on one scale.More in the glossary a session.

The real cost is concussions and the long-term effects of thousands of sub-concussive hits, which do not show up in death counts.

Why the deaths have changed

Football used to kill players through the head and neck. In the 1960s and 1970s, players were taught to tackle and block with the helmet first, and broken necks and fatal brain bleeds were common. Rule changes in 1976 banned using the head as the first point of contact, and the numbers fell. Deaths from collisions have kept falling: 27 at all levels in 2016–2025 against 49 in the decade before, a 45% drop.

Today most deaths are "indirect": the body fails under exertion. Since 2000, these have outnumbered collision deaths about 3 to 1. The main causes are:

• Heart problems, often an undiagnosed condition, which cause most exertional deaths.
• Exertional heat stroke, with 19 deaths in 2016–2025. Most happen in summer practice and conditioning.
• Sickle cell trait, a common inherited condition that is usually harmless but can cause collapse during intense, repeated sprints. Since the NCAA required players to know their status in 2010, deaths in top-division college football have fallen sharply.

Serious injuries short of death

In 2025 NCCSIR captured 39 catastrophic non-fatal injuries: 20 to the neck, 6 to the brain and 13 to internal organs and the chest. Eleven left the player with lasting damage. Neck injuries with incomplete recovery have halved since the late 1970s, to about 6 a year, but brain injuries with incomplete recovery have risen, from 2.4 a year in 1986–1990 to 5.2 a year in 2021–2025. Most happen to middle- and high-school players, almost always in games, and tackling causes more than half of the neck injuries.

Everyday injuries are frequent. In national surveillance from 2005 to 2014, high-school players lost at least a day to injury at a rate of 4.01 per 1,000 practices and games, and college players at 7.29. Games were 5.6 times riskier than practice in high school, and concussion was one of the most common injuries in games across most positions.

Concussion and CTE

Chronic traumatic encephalopathy (CTE) is a degenerative brain disease that can only be confirmed after death. In 2023 Boston University's CTE Center reported finding it in 345 of 376 former NFL players whose brains it had studied. That figure says less than it seems: families tend to donate brains when they have seen symptoms, so the sample over-represents players with problems.

The stronger evidence is the dose-response. In a 2020 study of 266 deceased players, the odds of CTE rose by 30% for every year of football played, doubling roughly every 2.6 years. Players with long careers, from youth football through college or the NFL, take by far the most head impacts.

How to play more safely

1. Acclimatise to heat over the first 14 days of preseason. Build up intensity and equipment gradually, check the wet-bulb temperature, and give plenty of water and rest breaks in the shade.
2. Make sure there is a cold-water tub or cooling tarp on site. The rule for heat stroke is "cool first, transport second": bring the core temperature down before the ambulance ride.
3. Know your sickle cell trait status and avoid repeated maximal sprints and conditioning tests without rest.
4. Have an athletic trainer and a defibrillator at every practice and game, with a written emergency plan.
5. Tackle with the head up and to the side. Coaches should limit full-contact practice; by 2016, 44 state high-school associations had rules limiting it.
6. Report concussion symptoms and sit out until cleared. A second hit before recovery is far more dangerous than the first.
7. Think about years of tackle football. Flag football before high school cuts head impacts without cutting the skills.

How we scored it

Fatality risk (88) is low, at about 0.1 micromortsMicromortA one-in-a-million chance of death. It lets you compare the risk of very different activities on one scale.More in the glossary per high-school session. Serious injury risk (35) is the weakest factor, because concussion is common and CTE risk rises with years played. Controllability (55) reflects how preventable today's exertional deaths are, and rescue (85) is good where an athletic trainer is present. Compare rugby, which has similar collision risks without helmets, and boxing, where blows to the head are the aim of the sport.