The Science of Addiction: How Substances Affect the Brain and Body

Whether it’s alcohol, opioids or stimulants, these substances all have one thing in common: they each have the distinct ability to hijack your brain’s natural reward system and cause addiction. 

Addiction is a complex brain disorder that creates cycles of cravings, dependence and withdrawals. For those deep in addiction, these substances fundamentally change the way we think, feel, and act.

What exactly happens to your brain and body during addiction, and can you ever truly recover?

Let’s examine how substances affect your brain and body, the long-term physical consequences of 5using substances, how to identify addiction and how to seek help.

The human brain: Tiny but mighty

The human brain is an incredibly complicated organ. Weighing in at only 1.3 kilos / 3 pounds, this tiny but mighty organ controls everything you do. From seeing, hearing, smelling, tasting and feeling, you’ll need a fully functioning brain to do anything. You are your brain.

A healthy brain has the unique ability to send messages back and forth through neurons. As these special cells fire up, they create neurotransmitters that “talk” to the rest of your body. Through this process, your brain transmits messages to your entire body: “Move your feet to walk up the stairs.” When our brain is functioning optimally, we don’t think about moving our feet to walk up the stairs; we just do it. But when our brain is affected by substance use, our neurons get confused and make us act in ways we normally wouldn’t.

When addiction takes over, our brain suffers the most. You see, substances fundamentally change your brain and make quitting difficult, even if you desperately want to quit using.

Why? Those neurotransmitters come into play again. When you use substances, dopamine is released in massive amounts, and this “reprograms” your brain to keep seeking out the drug to get that dopamine rush over and over. Your brain (and body) are now trained to crave the drug nonstop.

Your brain and body: Handle with care

The long-term implications of addiction vary widely depending on what types of substances are used. For example, cocaine affects your brain and body differently than heroin. But all substances cause massive damage to your brain and body.

Here are some of the top ways substances harm your brain and body:

Cirrhosis and fatty liver disease

Liver damage is caused by long-term, excessive alcohol use. The liver is a vital organ that helps flush out toxins, absorb nutrients and digest food. Without a healthy, functioning liver, individuals will have many health conditions such as jaundice, fluid retention, high cholesterol, hepatitis and, in extreme cases, complete liver failure, which results in death.  

Heart disease

Addiction puts a massive strain on your heart and cardiovascular system. With extensive drug and alcohol use, individuals experience high blood pressure, cardiovascular disease, cardiomyopathy and stroke.

Various Cancers

There is a clear link between alcohol and multiple cancers.

Recent studies show that alcohol may increase cancer risk in several ways by disrupting cell cycles, increasing chronic inflammation, and damaging your DNA. The Centers for Disease Control and Prevention states that when DNA is damaged, a cell can grow out of control and become cancerous.

Just one to three alcoholic drinks a day can have an increase in breast, pancreatic, stomach, mouth, liver, and esophageal cancers. There is no safe amount of alcohol that can be consumed that won’t put you at an increased risk of cancer. 

Diminished brain matter

Long-term alcohol abuse kills your brain cells and shrinks your brain structure. Without the necessary grey-and-white brain matter, you’ll have changes in your personality and metabolism while experiencing impulsive behaviour, impaired judgment, mood changes and aggression. Long-term alcoholics are also more likely to suffer from brain atrophy.

Irreparable digestive damage

Alcohol breaks down the lining of your stomach, increases acid production and impairs the absorption of vital nutrients. This digestive damage not only causes nutritional deficiencies but can also lead to painful ulcers, gastritis and a high risk of developing esophageal and stomach cancers.

Damage to the Central Nervous System

Those suffering from alcohol addiction might experience tingling, numbness and a notable cognitive decline. Long-term substance abuse also damages the central nervous system to the point that individuals can develop mental health disorders (bipolar disorder, anxiety, depression, borderline personality disorder), neuropathy and even brain damage.

Brittle bones and a weakened immune system

Long-term substance abuse leads to Vitamin D deficiency and a lack of calcium in your body. Without the proper nutrients, bones become brittle and weak, and individuals have an increased risk of osteoporosis, chronic pain, and fractures. Chronic alcohol drinkers also suffer from a weakened immune system and experience frequent illnesses, infections, and a slower recovery time.

Identifying addiction and seeking early intervention

By learning to identify the signs of addiction as early as possible, you can avoid some of the long-term health complications listed above and start getting the proper help and support you need.

Here are some signs and symptoms of substance addiction to watch out for:

• Changes in routine and priorities
• Decline in your physical and mental health 
• Relationship issues
• Erratic mood swings and emotional instability
• Using substances to cope at work
• Self-medicating to cope with a physical or mental health condition
• Using substances as soon as you wake up and continuing throughout the day
• Increasing levels of social withdrawal and isolation
• Inability to hold a job
• Lying to family and friends about your substance use
• Stealing to fund your substance use

If you or someone you love is exhibiting the behaviours of addiction, it’s time to seek help from outside professionals who can help with finding the correct inpatient treatment facility, the necessary medical detox and the right team of therapists.

How we can help: Addiction treatment in Ontario, Canada

Breaking the cycle of stigma, silence, and shame around addiction and substance abuse is a challenging but courageous act. It can help you get the support you need to feel better and encourage others to do the same.

If you are struggling with substance abuse and addiction, speaking to a professional can help. A mental health expert and addiction specialist can provide insight into your experiences and tailor a treatment program that works just for you.

At Centres for Health and Healing, we understand the science of addiction, so we provide holistic treatment programs that address the whole person—mind, body and spirit—not just their symptoms.

Whether you struggle with substance abuse, anxiety, depression, trauma, or other emotional difficulties, our programs are personalized to your individual needs and preferences.

The expert team at Centres for Health and Healing brings a wealth of experience and years of knowledge to each of our programs. We provide a safe and nurturing environment staffed with passionate and knowledgeable professionals.

Our programs include:

• Mental health treatment
• Trauma-informed treatment
• Individual and group therapy
• Inpatient treatment
• Medical detox (for substance use disorders)
• Mindfulness therapy
• Aftercare and support programs
• And much more

It’s never too late to start recovery. To learn more about Toronto’s Premier Mental Health & Addiction Treatment Centres, our alcohol addiction treatment program or our mental health treatment program, contact our professional team in Ontario, Canada, today and begin your journey to lasting transformation and recovery.