What is CBD? Simple Facts From Health Experts (2025 Guide)

CBD oil has been gaining attention in the health world, with medical professionals taking note since the FDA approved the first CBD-based medication for treating specific types of seizures. What exactly is CBD oil? CBD (cannabidiol) is one of the most prevalent active ingredients found in cannabis plants, but unlike THC, it doesn’t cause the “high” typically associated with marijuana.

The World Health Organization has reported that CBD shows no evidence of potential for abuse or dependence. Many people use CBD for various purposes including pain management, anxiety reduction and sleep improvement. However, while some research shows promising results for conditions like chronic pain and certain neurological disorders, it’s important to understand both the potential benefits and limitations of this cannabis-derived compound.

We asked health experts to explain what CBD is, how it works in the body, and what you should know before considering its use. This guide covers everything from basic properties to various applications and safety considerations, helping you make informed decisions about whether CBD might be appropriate for you.

What is CBD and how does it differ from THC?

Cannabis plants contain natural compounds called cannabinoids, with CBD (cannabidiol) and THC (tetrahydrocannabinol) being the most widely studied among hundreds of active ingredients. Although they share similar molecular structures, these compounds interact with our bodies in significantly different ways.

The key differences between CBD and THC

The main distinction between CBD and THC is their effect on the brain. THC directly activates CB1 receptors, producing the “high” typically associated with cannabis use. CBD, however, doesn’t cause intoxication, which is why it’s being explored for various therapeutic uses.

CBD works by influencing the endocannabinoid system indirectly and affects other signaling molecules like dopamine and serotonin. The two compounds also serve different medical purposes – THC is commonly prescribed for pain, nausea, and muscle stiffness, while CBD is more often considered for anxiety, epilepsy, and sleep problems.

Their side effects differ considerably too. THC can cause temporary effects including dry mouth, red eyes, memory impairment, and increased heart rate. Some research suggests regular or high-dose THC consumption might potentially trigger schizophrenia in people with genetic predisposition.

Hemp vs. marijuana: Where does CBD come from?

Both hemp and marijuana belong to the Cannabis sativa plant species, but their chemical compositions vary significantly. The critical difference is THC content – hemp plants contain 0.3% or less THC, while marijuana plants have higher THC concentrations.

Hemp naturally contains more CBD and minimal THC, making it the preferred source for CBD products. The 2018 Farm Bill removed hemp from the legal definition of marijuana in the Controlled Substances Act, which is why hemp-derived CBD products containing less than 0.3% THC are now legal at the federal level in the US.

Manufacturers typically extract CBD from hemp plant leaves and flowers to create oils, tinctures, and capsules. It’s worth noting that the extraction source matters legally rather than functionally – CBD’s effects remain the same whether it comes from hemp or marijuana.

Is CBD actually non-psychoactive?

The term “non-psychoactive” is often used to describe CBD, though this isn’t entirely accurate. Since psychoactive substances affect brain function and mood, CBD could technically qualify through its documented anti-anxiety, antipsychotic, and mood-altering properties.

A more precise description would be “non-intoxicating” – CBD doesn’t impair cognitive or motor functions like THC does. Instead of directly activating CB1 receptors as THC does, CBD primarily interacts with serotonin receptors, influencing mood and pain regulation without causing impairment.

This distinction helps explain why CBD may help with conditions like anxiety and epilepsy without producing the euphoric “high” associated with THC consumption.

How CBD works in the body

To understand how CBD works, we need to look at a remarkable biological network it influences. Our bodies have a built-in regulatory system that helps maintain balance across numerous functions—from mood and memory to inflammation and pain sensation.

Understanding the endocannabinoid system

The human body contains a complex cell-signaling network called the endocannabinoid system (ECS). This system helps regulate critical functions including sleep, mood, appetite, memory, and immune response. The ECS consists of three main components:

• Endocannabinoids: These are molecules naturally produced by your body (like anandamide and 2-AG) that bind to cannabinoid receptors
• Receptors: Found throughout the body, these receive signals from endocannabinoids
• Enzymes: These break down endocannabinoids once they’ve completed their function

This system essentially works to maintain homeostasis—the body’s version of internal balance—across many physiological processes.

How CBD interacts with our receptors

Contrary to what many believe, CBD doesn’t bind directly with the main cannabinoid receptors. Instead, it works through several different mechanisms:

CBD acts as a negative allosteric modulator of CB1 receptors, which means it can change the receptor’s shape, making it harder for compounds like THC to fully activate it. CBD also interacts with other receptors, notably TRPV1 (involved in pain and inflammation) and 5-HT1A serotonin receptors (affecting mood and anxiety).

There is evidence suggesting CBD may also influence the ECS by preventing endocannabinoids from breaking down, potentially enhancing their effects. This indirect approach helps explain why CBD produces subtle yet meaningful effects on multiple bodily functions.

Why CBD doesn’t cause intoxication

The reason CBD doesn’t cause a “high” stems primarily from how it interacts with receptors. While THC directly activates CB1 receptors in the brain, triggering the characteristic “high,” CBD works differently by blocking this activation.

CBD is actually a CB1 antagonist—it interferes with CB1 activation rather than stimulating it. This explains why CBD not only doesn’t cause intoxication but may actually reduce THC’s psychoactive effects when both compounds are present.

It’s this unique interaction with our body’s systems that allows CBD to offer potential therapeutic benefits without impairing cognitive or motor functions.

What is CBD oil used for?

Research continues to uncover potential therapeutic applications for CBD across various conditions. Despite its growing popularity, scientific evidence varies considerably for different uses. Here’s what current research tells us about CBD’s most common applications:

1. Pain and inflammation

The evidence for CBD’s effectiveness against pain presents a mixed picture. While some animal studies and small human trials suggest potential pain-relieving properties, other research challenges these findings. A systematic review in Cureus concluded that CBD could help reduce pain in conditions like arthritis and fibromyalgia. Nevertheless, a University of Bath study found no evidence that CBD products reduce chronic pain, suggesting they might be “a waste of money”. Interestingly, one study reported that 87% of participants sought medical marijuana specifically for pain relief.

2. Anxiety and stress

Research increasingly supports CBD’s potential for managing anxiety disorders. A 2023 systematic review suggested CBD might improve anxiety-related symptoms. Early studies have explored how CBD may alleviate anxiety through its interaction with serotonin receptors. One particularly striking finding showed that 39% of people who are married reported high levels of anxiety. Clinical trials have demonstrated CBD’s positive effects on social anxiety disorder, with one 2019 study showing improvement in teenagers with this condition.

3. Sleep problems

CBD may help people fall asleep faster and potentially stay asleep longer. Research suggests its sleep benefits might come partially from addressing underlying issues like chronic pain and anxiety. According to studies, CBD can lengthen sleep and alter REM sleep patterns, making it potentially useful for those struggling with insomnia.

4. Seizure and epilepsy

Epilepsy represents CBD’s most scientifically validated application. The FDA-approved medication Epidiolex (cannabidiol) effectively treats seizures in Lennox-Gastaut and Dravet syndromes. Clinical trials found that 43% of people with Dravet syndrome experienced at least a 50% reduction in convulsive seizures when taking CBD. The typical starting dose is 2.5 mg/kg twice daily.

5. Other emerging uses

Beyond these established applications, researchers are exploring CBD for:

• Neurodegenerative conditions (Parkinson’s, Alzheimer’s)
• Multiple sclerosis symptoms
• Addiction treatment (tobacco, heroin cravings)
• Treatment-resistant PTSD

It’s important to note that while some of these applications show promise, many require further research through randomised, placebo-controlled studies before definitive conclusions can be drawn about CBD’s effectiveness for these conditions.

Is CBD oil safe? Side effects and considerations

While CBD oil shows promise for various health conditions, understanding its potential effects and safety profile is crucial before adding it to your wellness routine.

Common side effects of CBD oil

Although most people tolerate CBD well, side effects can occur. The most frequent reactions include dry mouth, drowsiness, and light-headedness. Some people may also experience gastrointestinal issues like diarrhoea or changes in appetite.

For those taking high doses, more serious concerns emerge. Liver function abnormalities have been reported with the prescription form of CBD (Epidiolex), which is why doctors often recommend periodic liver enzyme monitoring.

The Food Standards Agency has updated its advice to recommend that healthy adults limit CBD consumption to 10mg per day (approximately 4-5 drops of 5% CBD oil). This guidance stems from concerns that prolonged exposure to higher amounts might potentially lead to long-term adverse effects.

CBD and medication interactions

CBD can compete with liver enzymes that metabolize medications, potentially increasing blood levels of certain drugs. This interaction (sometimes called the “grapefruit effect”) warrants caution when combining CBD with:

• Blood thinners like warfarin, where CBD may increase bleeding risk
• Anti-epileptic medications, especially clobazam
• Sedatives, which combined with CBD could cause excessive drowsiness
• Immunosuppressants and heart medications

If you’re taking any prescription drugs, you should speak to your GP or healthcare professional before using CBD products—even for topical applications.

Choosing safe, tested CBD products

The CBD market remains largely unregulated, making quality control your responsibility. When selecting CBD products, look for:

1. Third-party testing certificates that verify CBD content matches the label and confirm THC levels fall below legal limits (0.3% in US, 1mg per container in UK)
2. ISO-accredited laboratory analysis rather than unaccredited testing, as this higher standard is recognized by regulatory bodies
3. Organic certification that ensures your product is free from pesticides, heavy metals, and other contaminants

It’s worth noting that studies show more than 25% of CBD products contain less CBD than advertised, with some containing illegal THC levels. For this reason, proper product vetting becomes an essential step before trying CBD.

This is particularly important as there are few licensed CBD products available in the UK, and caution should be exercised if considering over-the-counter products.

Should you try CBD oil?

CBD oil has emerged as an interesting compound that offers potential health benefits without THC’s intoxicating effects. Through its interaction with our endocannabinoid system, CBD may provide benefits ranging from seizure control to anxiety management, though effectiveness varies considerably among different conditions.

Scientific evidence most strongly supports CBD’s role in treating specific forms of epilepsy, where there are licensed products available in the UK. Research continues to explore its potential for pain relief, sleep improvement, and stress management, with mixed results so far. It’s important to understand that CBD isn’t a miracle cure – its effects can differ significantly between individuals.

Safety should be your primary concern when considering CBD use. Careful product selection, proper dosing, and awareness of potential drug interactions make the difference between beneficial use and unnecessary risks. If you’re considering using CBD oil, you should speak to your GP or other healthcare professional to ensure that it is safe and appropriate for you to do so. This is particularly important if you are taking prescription medications.

As research advances, our understanding of CBD’s capabilities and limitations continues to grow. Though many questions remain, CBD’s documented benefits for certain conditions and generally favourable safety profile suggest it will maintain its place in therapeutic applications, particularly when chosen and used thoughtfully.

All health content is provided for general information only, and should not be treated as a substitute for the medical advice of your own doctor or other healthcare professional.

Have you tried CBD oil for any health conditions? What was your experience like? Let us know in the comments below.

FAQs

Q1. What exactly is CBD and how does it differ from THC? CBD is a non-intoxicating compound found in cannabis plants. Unlike THC, it doesn’t cause a “high” and interacts differently with the body’s endocannabinoid system. CBD is often derived from hemp and has various potential therapeutic applications.

Q2. How does CBD work in the human body? CBD interacts with the body’s endocannabinoid system, which regulates functions like sleep, mood, and pain sensation. It doesn’t directly bind to cannabinoid receptors but influences them indirectly and affects other signaling molecules, potentially offering therapeutic benefits without impairing cognitive functions.

Q3. What are the main uses of CBD? CBD is being researched for various potential uses, including pain and inflammation relief, anxiety and stress management, sleep improvement, and seizure treatment. It’s FDA-approved for certain types of epilepsy and shows promise for other conditions, though more research is needed in many areas.

Q4. Are there any side effects or safety concerns with CBD use? While generally well-tolerated, CBD can cause side effects like dry mouth, drowsiness, and gastrointestinal issues. It may also interact with certain medications. It’s important to choose quality-tested products and consult a healthcare provider before use, especially if you’re taking other medications.

Q5. How can I ensure I’m using CBD safely? To use CBD safely, look for products with third-party testing certificates, choose organic options when possible, and adhere to recommended dosage guidelines. It’s crucial to consult with a healthcare professional before starting CBD, particularly if you have existing health conditions or are taking medications.