Bike Helmet Safety: Should You Wear a Helmet or Not?

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If you ride a bike, it’s super important to wear a helmet to protect your head. Without a helmet, bike accidents are way more likely to cause serious brain injuries or even death.

A bicycle safety study from New York City revealed that 74% of bike crashes involved a head injury, and 97% of cyclists who died were not wearing a helmet.

There are several other disturbing statistics like this, yet many cyclists choose not to wear a helmet. 

Many people who do not wear helmets think that helmets are not very effective. So we decided to examine how helmets work, what makes them safe, how effective they are at preventing head injuries and keeping us alive, and many more. 

What makes a helmet safe? 

“Helmet saves lives” If we’ve heard it once, we’ve heard it a thousand times. But how exactly does a helmet work? What is it about a helmet that makes it effective at preventing fatal head injuries during a bike crash?

First off, a helmet helps to reduce the risk of serious head and brain injury by minimizing the impact of a collision or blow to the head. A helmet protects the head in three ways:

  • It cushions the head to prevent direct contact between the head and the object of collision.
  • It distributes the force of the collision over a larger surface area, preventing them from being focused in one particular region of the head.
  • And finally, it absorbs some of the collision force, which lessens the force that is sent to the head to reduce the extent of the trauma.

Let’s look at the design elements of the helmet that makes it effective at preventing head trauma. There are 2 main parts of the helmet that contribute to its safety; the outer shell and the impact-absorbing liner. 

The outer shell

A helmet’s outer shell is the hard, outermost layer of the helmet. It’s the first line of defense and is responsible for dispersing the impact energy in the event of an accident. 

In the event of a crash, the outer shell will be the first part of the helmet to come in contact with another object, be it the ground or a vehicle. 

And by spreading the force of the impact over a larger area, it helps to reduce the amount of force the head receives on impact, which is important in preventing serious injury to the skull and brain. 

The outer shell of a helmet is often made of hard plastic or composite materials with the ability to absorb and disperse impact energy—like thermoplastic, carbon fiber, or fiberglass.

How well a helmet protects the head is affected by the thickness and shape of its outer shell. A thicker shell can absorb more impact energy, while a more aerodynamic shape can help to reduce the likelihood of rotational forces that can cause brain injury.

Finally, the shell also helps to prevent sharp objects from penetrating the helmet and causing injury.

It’s important to note that the outer shell is just one part of the helmet and works in conjunction with other components, such as the impact-absorbing liner and retention system, to provide optimal protection.

The impact-absorbing liner

This is the part of the helmet that absorbs the force of impact. The liner is typically made of expanded polystyrene foam, which is designed to absorb and disperse the force of an impact.

When a rider falls or is involved in a crash, the EPS foam compresses to absorb the impact energy and reduce the force that is transmitted to the rider’s head. 

The liner is typically thicker in areas that are more vulnerable to impact, such as the forehead and temples. 

A helmet’s shell and liner work together to provide maximum protection. The outer shell is designed to disperse the impact energy by spreading the force of the impact over a larger area. 

While the impact-absorbing liner is responsible for absorbing and dissipating the energy, eventually reducing the amount of energy transmitted to the rider’s head. 

Retention system

The retention system keeps the helmet on the rider’s head and helps to disperse impact energy. 

In the event of an accident, it keeps the helmet’s impact-absorbing part firmly attached to your head, so that it can effectively provide its cushioning effect. 

This part of the helmet should be adjustable and provide a snug, comfortable fit.

Other parts of the helmet that help to make it safe for riders include:

  • Chinstrap: The chinstrap keeps the helmet securely on the head and prevents it from coming off during an accident. It should be adjustable, comfortable, and easy to fasten and release.
  • Visor: This works to protect the rider’s face from debris, wind, and the sun’s glare. It’s often made of shatterproof material and offers clear visibility.
  • Ventilation system: The ventilation system of a helmet is responsible for keeping the rider cool and comfortable by allowing air to flow through the helmet. It also helps to prevent excessive wind noise and turbulence.
  • Padding: Helmets have padding that provide a comfortable fit and helps to absorb sweat. Ideally, helmet padding should be removable and washable for easy maintenance.
  • Helmet shape: The helmet should be designed to fit the head’s shape and provide full coverage of the forehead and back of the head.

It is important to note that all of the individual parts of the helmet work together to provide maximum protection. A helmet with a weak or missing component will not offer adequate protection in the event of an accident.

How effective are bike helmets in preventing injury and death?

If you find yourself wondering how effective bike helmets are, you’re not alone. Many cyclists, including myself, have asked this question at least once. 

But one thing is clear, a helmet is a crucial piece of safety gear for reducing the risk of head injuries while cycling.  

There have been several studies that prove the efficacy of bike helmets.

One such study, for instance, stated that wearing a helmet reduced the risk of head injury by 63% and of loss of consciousness by 86% [1]. 

Similarly, another study recorded that cyclists wearing helmets involved in motor vehicle collisions were 78.6% less likely to be diagnosed with a head injury compared to cyclists without helmets [2].

Also, when a head injury was diagnosed, cyclists who wore helmets were 44% less likely to sustain a severe head injury [2]. 

A 2022 study from the Children Hospital of Philadelphia revealed that nearly 87% of kids with skull fractures were not wearing helmets.

Several other studies have conclusively stated that bicycle helmets will effectively reduce fatal head and face injuries in cyclists involved in crashes.

However, helmets don’t always provide full injury protection, and depending on the kind of injury, they may or may not be as effective. 

When riding, the risk of injury and death can be decreased by wearing a properly fitted helmet, but most importantly, always ride safely.

What percentage of cyclists wear helmets?

Since bike helmets are so effective at preventing head injuries during a fatal bike crash, you’d expect that more cyclists will subconsciously grab their helmet when going for a ride, right? Yes, of course, it’s a no-brainer!

But that’s not what actually happens. In fact, many cyclists don’t care for helmets. In the US, for instance, less than 30% of adult cyclists will wear a helmet. Even more shocking is that more than half of adult cyclists in the US report never wearing a helmet [3]. 

On a global scale, the percentage is much lower; only 18% of riders do so. This is even more worrisome considering that head injuries occur in up to 70 to 80% of all fatal bicycle accidents.

Do bike helmets really prevent death?

In some instances, bike helmets can prevent death, especially when a head injury results from an accident. The sort of accident and the force of the impact are two variables that can affect how effective a bike helmet is.

While studies have shown that wearing a helmet can lower the chance of head injury and serious brain injury, which can eventually save lives, they cannot offer complete protection from injuries.

But how much death do helmets prevent, let’s look at the numbers.

How many deaths are caused by not wearing a helmet

The statistics below were collected from different reliable sources.

  • Cyclists who died of a head injury were three times as likely to not be wearing a helmet compared with those who died of other injuries, according to a study.
  • In 2020, 57% of cyclists killed in crashes were not wearing helmets [4].
  • In 2016, half of the cyclists who died in crashes were not wearing a helmet [5].
  • In 2014, over 60% of deaths in bicycle crashes were people who were not wearing a helmet [6].
  • An analysis of between 76,032 cycling injuries between 2002 and 2012 revealed that 78% of adult cyclists and 88% of young riders who suffered head and neck injuries were not wearing helmets when they were injured.

How many lives are saved by helmets 

Bicycle helmets save lives by reducing the risk of head injury and the risk of brain injury. It has also been proven that bicycle helmets provide significant protection for the forehead and mid-face.

The statistics below were collected from different reliable sources.

  • An estimated 75% of bicycle-related fatalities among children could be prevented with a bicycle helmet.
  • According to this study, the use of bicycle helmets was found to reduce serious head injury by 60%, traumatic brain injury by 53%, and the total number of killed or seriously injured cyclists by 34%.
  • Another study, by the American Journal of Surgery, concluded that cyclists with helmets were 44% less likely to die from their injury, and 31% less likely to break facial bones.
  • Statistics from Safe Kids International estimates that the universal use of bicycle helmets by children between the ages of 4 and 15 could prevent about 135 to 155 deaths, and 39,000 to 45,000 head injuries every year [6].

How much do helmets reduce head injuries?

It’s interesting to see how the singular act of wearing a helmet can be a lifesaver. So, let’s look at the percentage of head injuries (especially severe and traumatic injuries) reduced by wearing a helmet.

  • A study conducted by the University of NSW found that wearing a helmet reduced the risk of head injury by 51%, serious head injuries by 69% and facial injuries by 33% [7].
  • Similarly, a meta-analysis of 55 studies of the effects of bicycle helmets on injuries concluded that the use of bicycle helmets was found to reduce head injury by 48%, serious head injury by 60%, and traumatic brain injury by 53%.

What happens if you don’t wear a helmet? 

We have already established that bike accidents where cyclists did not wear helmets are more likely to cause death or brain trauma compared to crashes where cyclists were protected with helmets. 

Therefore, it’s safe to say that cyclists who do not wear helmets are at a much higher risk of severe head injury, trauma and death. 

Not wearing a helmet when cycling will leave you vulnerable to several injuries during a crash. A helmet will protect you from injuries like:

  • Trauma to the head
  • Broken facial bones
  • Concussion

Always wear a helmet when riding a bicycle. Also, verify that the helmet meets the U.S. Department of Transportation safety regulations and it fits properly. Your helmet should be made of high-quality materials and never involved in a crash.

What about neck injuries?

One of the most common defenses used against Mandatory helmet laws is that while head injuries may well be avoided, neck injuries will happen more frequently. 

Is there any truth in this statement, or is it a myth?

Well, experts don’t seem to agree. Previous studies have explored the possibility of a link between wearing a helmet and neck or facial injuries. 

One study discovered that wearing a helmet protects against injuries to the top and middle faces—but does not protect the lower face—with conflicting evidence regarding neck injuries.

But that’s not all! 

According to a systematic review published by the International Journal of Epidemiology, use of a bicycle helmet was linked to lower chances of suffering a fatal head injury or facial injury during a crash, but neck injuries were uncommon and unrelated to wearing a helmet.

So we can safely say that bicycle helmets may not adequately protect the lower face and neck, but they do not cause neck injuries.

Is it compulsory to wear a helmet when cycling?

Yes and no. The actual answer to this question varies depending on the country, state, or city you’re cycling in. 

Many states and cities require cyclists to wear a helmet, especially for children under a certain age. However, there are some places with no legal requirement to wear a helmet when cycling.

It is highly recommended that you wear a helmet when cycling, even if it is not required by law in your area. Helmets can significantly reduce the risk of head injuries in the event of a fall or accident while cycling. Also, it’s important to make sure that your helmet is properly fitted and adjusted to provide maximum protection.

In the United States, there is no federal law that requires individuals to wear a helmet when cycling. So helmet laws are determined at the state and local levels. As a result, helmet laws can vary across different states and cities within the US.

Currently, 22 states and the District of Columbia have laws that require cyclists to wear helmets in certain circumstances, such as when cycling on public highways or when riding with a child passenger. These states are:

StateHelmet law
AlabamaMandatory for all cyclists
California Mandatory for all cyclists
Connecticut Mandatory for all cyclists
DelawareMandatory for all cyclists
District of ColumbiaMandatory for all cyclists
FloridaMandatory for all cyclists
Georgia Only for cyclists under 16
Hawaii Only for cyclists under 16
Louisiana Only for cyclists under 12
Maine Only for cyclists under 16
MarylandOnly for cyclists under 16
Massachusetts Only for cyclists under 17
Michigan Only for cyclists under 20
New HampshireOnly for cyclists under 16
New Jersey Only for cyclists under 17
New York Only for cyclists under 14
North CarolinaOnly for cyclists under 16
Oregon Only for cyclists under 16
PennsylvaniaOnly for cyclists under 12
Rhode Island Only for cyclists under 16
Tennessee Only for cyclists under 16
Virginia Only for cyclists under 14

In addition to these states, some cities and municipalities may have their own helmet laws. It is always a good idea to check the local regulations before cycling to ensure that you are in compliance with any helmet laws that may apply.

Why do people not wear bike helmets?

It’s been proven again and again that helmets indeed protect against severe head injuries during a bike crash and can actually save lives, yet many cyclists do not wear them. 

In fact, more than half of all cyclists do not wear a helmet and only 11% of teens wear a helmet when cycling [8]. This is concerning, especially because 67% of bicycle-related head injuries in teens are associated with not wearing a helmet. 

Some argue that teens don’t wear helmets because they believe they are invincible, or that helmets are uncool and unnecessary. 

Some even argue that skilled riders shouldn’t wear helmets, but this argument fails to realize that bike crashes are not always the rider’s fault. 

For instance, data from the U.S. Department of Transportation’s Fatality Analysis Reporting System (FARS) revealed that in 2020, 32% of cyclist deaths occurred at intersections and 61% of cyclist deaths occurred on major roads other than interstates and freeways [4].

It’s simply not possible that every single crash that led to these deaths were caused by a careless or inexperienced cyclist. According to the National Highway Traffic Safety Administration, getting hit by a car is the most common cause of bicycle accidents. 

This shows that the cyclist may not be at fault in many crash cases, and bicycle-vehicle collisions are also caused by careless or distracted drivers. 

So, the argument that skilled cyclists shouldn’t bother with helmets doesn’t hold water. 

Another reason some cyclists give for not wearing helmets is that helmets may protect against head injuries, but they cause neck injuries. We already discussed this earlier, and found a study with the conclusion that neck injuries were uncommon in bike crashes and are not related to wearing a helmet. 

Another argument against the mandatory use of helmets is that they are not as effective, and don’t always prevent death. Of course, helmets don’t always prevent death, but we cannot deny the fact they work when used properly. 

Several studies have established that helmets significantly reduce the risk of severe head injuries and traumatic brain injuries by up to 63 to 88%.

Many people who choose not to wear a helmet while cycling do so for what they perceive to be valid reasons. However, it’s important that cyclists wear a helmet and also ride carefully and responsibly. 

Consequence of not wearing a bicycle helmet

Head injuries. Increased risk of death. Higher medical costs. Longer recovery time

The consequences of not wearing a bicycle helmet can be serious, especially if you are involved in a crash or accident while cycling. Here are some of the potential risks:

Head injuries

The most significant risk of not wearing a helmet is the potential for head injuries. In the event of an accident, a helmet can help protect your head from impact with the ground, other objects, or other vehicles. Without a helmet, you are more likely to suffer a head injury, which can range from mild to severe and potentially life-threatening.

Increased risk of death

Studies have shown that wearing a helmet can significantly reduce the risk of death in the event of a bicycle accident. In some cases, a helmet can mean the difference between life and death.

Legal consequences

As mentioned earlier, some states and cities have laws that require cyclists to wear helmets. If you are caught cycling without a helmet in an area where it is mandatory, you may face legal consequences such as fines or penalties.

Higher medical costs

If you suffer a head injury while cycling without a helmet, you are more likely to require medical attention and treatment, which can be costly. Medical costs for head injuries can be especially high if you require hospitalization or surgery.

Longer recovery time

In the event of a head injury, recovery time can be significantly longer if you were not wearing a helmet. This can impact your ability to work or engage in other activities, and can also impact your quality of life.

Remember that not wearing a bike helmet can have very dire consequences. It is always a good idea to wear a properly fitted helmet when cycling.

5 Reasons to wear a helmet!

There are several important reasons to wear a helmet when cycling, including:

Head protection

The primary reason to wear a helmet is to protect your head in the event of a crash or accident. A helmet can help absorb the impact of a fall or collision and reduce the risk of serious head injuries such as concussions, skull fractures, and brain injuries.


Wearing a helmet can help make you more visible to other cyclists, pedestrians, and motorists, which can increase your safety when cycling on the road or in other public spaces. A helmet can also help protect your face and eyes from debris, bugs, and other hazards.

Legal requirements

We mentioned earlier that some states and cities have laws that require cyclists to wear helmets in certain situations. If you are caught cycling without a helmet in an area where it is mandatory, you may face legal consequences such as fines or penalties.

Setting a good example

Wearing a helmet can set a good example for others and help promote safe cycling practices. When others see you wearing a helmet, they may be more likely to do so as well.


Helmets are designed to be comfortable and lightweight, and many models come with adjustable straps and ventilation to help keep you cool and comfortable during your ride.

Keep in mind that wearing a helmet is an important safety measure that can protect your head and reduce the risk of serious injuries in the event of a crash or accident. It is also often required by law, can set a good example for others, and can be comfortable and convenient to wear.

Finally, always wear a helmet and ride safely!

Even though helmets do not prevent bike crashes or guarantee survival, they can significantly lower the risk of suffering a major brain or head injury. 

During a bike crash, a helmet will protect your head by preventing direct contact between the impacting object and your head. 

It also absorbs some of the collision force and distributes it over a larger surface area, preventing them from being focused in one particular region of the head. 

A helmet still does an amazing job of protecting you from serious injury and death, even if it isn’t 100% perfect.

You will agree with me that surviving a crash without suffering a significant brain injury is much better than surviving with a serious brain injury.

While it’s up to you to wear a helmet, we strongly recommend it because we’ve seen how devastating head injuries can be for cyclists.

Wearing a helmet also doesn’t excuse you from riding safely and responsibly. Helmets save lives, but so does careful cycling. 

Always wear a helmet and bike safely!

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