11 Fun Facts About Your Brain
3 Pounds of Remarkable Matter
Updated June 2024
Your brain is one of the most complex and fascinating organs in your body. It’s made up of billions of neurons (or nerve cells) that communicate in trillions of connections called synapses. Keeping your brain healthy and active is vital. Discover just how powerful your brain is with these interesting facts compiled by Kapil Sachdeva, MD, a neurologist at Northwestern Medicine.
Your brain’s storage capacity is considered virtually unlimited.— Kapil Sachdeva, MD
- Sixty percent of the human brain is made of fat, making it the fattiest organ in the human body. These fatty acids are crucial for your brain’s performance, so make sure you’re fueling it with healthy, brain-boosting nutrients.
- Your brain isn't fully formed until age 25. Brain development begins from the back of the brain and works its way to the front. As a result, your frontal lobes, which control planning and reasoning, are the last to strengthen and structure connections.
- Your brain’s storage capacity is considered immense. Research suggests the human brain consists of about 86 billion neurons. Each neuron forms connections to other neurons, which could add up to 1 quadrillion (1,000 trillion) connections. Over time, these neurons can combine and further increase storage capacity. They can also become damaged and stop working, such as in diseases like Alzheimer’s disease, affecting memory in particular.
- Brain information can travel up to an impressive 350 miles per hour. When a neuron is stimulated, it generates an electrical impulse that travels from cell to cell.
- On average, your spinal cord stops growing at 4 years old. Your spinal cord consists of a bundle of nervous tissue and support cells that are responsible for sending messages from your brain throughout your body.
- The spinal cord is the main source of communication between the body and the brain. Amyotrophic lateral sclerosis (ALS) causes the neurons in the brain and spinal cord to die, impacting controlled muscle movement. Multiple sclerosis (MS) is another disease that affects both the brain and the spinal cord. In MS, the immune system attacks the protective layer that covers nerve fibers, causing communication problems between the brain and the body.
- It’s a myth that you only use 10% of your brain. You actually use all of it, even when you are sleeping. Neurologists confirm that your brain is always active.
- The average adult human brain weighs about 3 pounds; that’s about as much as a half-gallon of milk. Men* tend to have slightly larger brains than women, but this does not impact intelligence.
- A brain freeze, medically known as sphenopalatine ganglioneuralgia, occurs when cold hits the receptors in the meninges, the outer covering of the brain. The cold causes a contraction and then a dilation of arteries, triggering a rapid-onset headache.
- A piece of brain tissue the size of a grain of sand contains 100,000 neurons and 1 billion synapses. However, damage to neurons can have great impact. For example, during a stroke, blood cannot get oxygen to the brain. As a result, brain cells can die, and abilities in that particular area of the brain can be lost. Similarly, Parkinson’s disease occurs when cells in a part of your brain called the substantia nigra start to die.
- The human brain runs on about 20 watts of power (enough to power a lightbulb). All that power calls for some much-needed rest. Adequate sleep helps maintain the pathways in your brain. Additionally, research shows that sleep deprivation is linked to Alzheimer’s disease.
Your brain has a big job. Be sure to take care of it.
* Scientists do not always collect information from participants about gender identity. To avoid misrepresenting the results of this research, we use the same terminology as the study authors.