Last fall, I went with my 12-year-old son to his middle school’s opening home football game. The bleachers were lined with parents, the smell of hot dogs and nachos wafted over the field, the announcer’s voice blared, and the cheerleaders jumped out of sync.

The boys were dressed in shoulder, chest, thigh and kneepads covered with clean white numbered uniforms. They each wore a helmet that seemed to weigh more than their head.

It reminded me of the days when I played Pop Warner football in the suburbs of Boston 35 years ago. I was a skinny tight end who spent more time getting hit in practice than in the games, but it was the route to my dream of becoming an NFL player. Even though my parents discouraged me, I insisted on playing tackle football with some kids twice my size.

Football is in our blood. My hometown of Needham, Mass., has had what must be one of the longest Thanksgiving Day high school football rivalries in history — 124 years — with neighboring Wellesley. My favorite team, the New England Patriots, and my wife’s favorite, the New York Giants, made for a divisive Super Bowl party at our house this January.

Yet for me the toughness and glory of football began to tarnish when report after report showed that the brains of football players were being adversely impacted. At first I was hoping the data would go away or be false, but the findings only get worse.

A 2000 study of more than 1,000 NFL players showed that 26 percent of players who had suffered three or more concussions were more likely to have memory deficits, poor concentration, speech impairments and headaches.

A 2007 study showed that retired NFL players with concussions were three times more likely to develop depression.

A 2009 study by the NFL Commission found that Alzheimer’s disease or other memory problems were occurring at a rate 19 times greater among football players ages 30 to 49. All this has led to many rule changes regarding concussions and better standards on helmets.

But what about high school or middle school football? Sitting on the bleachers and watching my son’s friend take a hit in the chest — I felt it in mine. There were no concussions in the game, but there easily could have been.

A brain, which I held in my hands in my medical school anatomy class, is a Jell-O-like walnut-shaped mass surrounded by a sac of fluid and then sheltered by a bony calcium shell, our skull. A hit to the head ricochets the brain inside the skull, disrupting billions of brain cells. If the impact is significant enough, it leads to loss of consciousness.

The brain of a middle school or high school student is more vulnerable to injury because it is still developing. The father of New England Patriots quarterback Tom Brady said that he is not certain if he would have let his son play football if he knew about the long-term health risks.

What concerned me most was a May 2012 study of former college athletes who had played a contact sport. Some had sustained a concussion. MRIs of players 30 years later showed the concussed brain had aged 10 years more than an uninjured brain, with less volume in the hippocampus (which is the memory area), thinner cortexes (the thought and consciousness area), metabolic slowing of brain cells, and radiological changes similar to Alzheimer’s disease. Fortunately, the former athletes in the study did not have significant clinical memory loss or cognitive problems.

What should we do? Pop Warner, the nation’s largest youth football organization with nearly 300,000 children ages 5 to 15, has changed its rules effective this month. There will be no contact for two-thirds of the practice — because research shows that in youth football the hardest hits occur during practices. Also, no head-to-head contact or full-speed head-on blocking will be allowed. A neurologist for the Pop Warner advisory board believes this will eliminate 60 percent of the brain impacts or concussions.

So what persuaded the Pop Warner officials to make this change? A study on second-graders, published in February 2012, in which researchers put sensors in the helmets of the youngsters, found an average player sustained 100 head impacts over a season. Most were minor, but some were at the force of college-level football.

Parents and school coaches have a choice this fall. I believe few, if any, of our children will likely play for the NFL, but all will require their brains to be functioning at peak capacity when they are adults, not aging at a faster pace.

We need to be concerned about the long-term consequences of middle school tackle football. We have an option. The skills of passing, catching, running and kicking can all be developed in flag-football, which would significantly reduce the risk of head injuries.

I hope my son never asks me if he can play tackle football.

Manoj Jain is an infectious disease physician and contributor to the Washington Post and The Commercial Appeal, where this post originally appeared.  He can be reached at his self-titled site, Dr. Manoj Jain.