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Jawzrsize and similar products or programs involve chewing on a silicone ball to reportedly strengthen and lift the facial and jaw muscles. While some people may report benefits, there are also some risks to consider.

In this article, we will discuss what the Jawzrsize is, its effectiveness, and any possible side effects it may have.

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Jawzrsize is the name of a device designed to give a workout to the jaw. The device itself is a hollow, ball-shaped piece of rubber. It includes silicone inserts designed to mold to the teeth and a person’s own bite to make the tool more comfortable to use.

After shaping the device to the person’s own teeth and bite, the exercise is simple. The user bites down on the silicone ball to provide resistance to the jaw muscles. The company offer a number of devices with different resistance levels, delivering from 20 to 50 pounds of resistance.

The Jawzrsize workout includes biting down on these resistance balls multiple times for 20–30 minutes at a time. Proponents of the workout suggest that it may increase muscle strength in the jaw and improve the shape and tone of the face over time.

The theory behind the tool is that the modern person does not chew as much as their ancestors did, which causes a deterioration in the facial muscles. Using this tool then allows the person to retrain these muscles.

The Jawzrsize device provides resistance to the jaw during each bite. As such, it may help strengthen the jaw muscles. An older study evaluating a similar silicone bite device found that it did increase maximum bite force and endurance. However, after the participants of the study stopped training, the results rapidly disappeared.

Endurance training for the jaw may have some use in helping people recover from jaw disorders. For example, a 2019 study found that those with jaw pain who performed endurance training had lower markers of pain after 8 weeks.

However, the claim that the device provides a workout that the body does not normally get may be unfounded. In healthy individuals, the jaw and facial muscles get plenty of exercise from chewing, talking, or making facial expressions.

Chewing gum is another common way many people provide similar exercise for their jaw. A 2018 study notes that chewing gum may help train the jaw to have a stronger force when biting, and it may be helpful with weaker jaws.

According to the Jawzrsize website, the device is designed to work out the full range of the jaw as it bites. They state that this can give the jaw and face a stronger, leaner look. Proponents suggest that it may also help create a chiseled jaw and reduce fat on the face.

Using the Jawzrsize may lead to some enlargement, or hypertrophy, of the masseter muscles, which are large chewing muscles at the side of the face. However, while it may help strengthen the jaw, it is unlikely to provide other benefits.

The chewing, or masticatory, muscles do not tone or rejuvenate the face. They are simply the muscles involved in chewing. Exercising these muscles is not likely to alter a person’s face substantially.

Actively training these muscles is also unlikely to lead to a reduction of fat on the face. It is not possible to target exactly where a person will lose fat. Instead, regular exercise and a healthful diet can help facilitate weight loss.

That said, some people may experience some benefits from using these devices. Anecdotally, users say it helps reduce pain and strengthen their jaw muscles.

While resistance devices may increase jaw strength, they also come with potential risks. The jaw gets plenty of exercise throughout normal activities during the day. Adding even more exercise may put the muscles at risk of issues, which may include:

  • Temporomandibular joint (TMJ) disorders: Research suggests that long durations of chewing or clenching the jaw may result in TMJ disorders, which cause pain in the jaw joint and supporting muscles.
  • Dislocation: It may result from excessive chewing and cause the jaw to pop or click. It can also lead to TMJ disorders.
  • Headaches: A 2015 study suggests there may be a link between chewing and headaches, particularly in those prone to tension headaches or migraines. Therefore, it may be advisable for certain people to avoid using chewing devices.
  • Dental problems: These may occur due to the force and excessive chewing in people with weaker teeth or other oral health issues.

Instead of using a chewing device, a person can chew gum to get similar benefits. Chewing gum may also help improve cognition. However, more research exploring this link is necessary. People should also be aware of any sugars in the gum and the gum being a potential choking hazard.

If a person has any concerns that they have a weak jaw or want it to be more functional, they should discuss it with their doctor.

The Jawzrsize device may help strengthen the muscles associated with chewing and biting. Proponents of the device claim that this will have numerous benefits for the face. However, there is not much scientific evidence to support this.

There are some risks of overexertion from using these devices, and the force of using them may pose risk to the mouth and teeth. The devices may also be unnecessary for most people, as the jaw gets plenty of exercise from daily activities, such as chewing and talking.