CBD oil has become the most consumed form in Europe since 2022: practical, precise, discreet. But the market has become a jungle — 5 %, 10 %, 20 %, 30 %, full spectrum, broad, isolate… Here's the structured guide to not get it wrong.
What is CBD oil exactly?
A CBD oil contains two elements:
- A hemp extract rich in CBD (and depending on type, other cannabinoids: CBG, CBN, CBC, trace THC).
- A vegetable carrier oil that dissolves CBD: MCT oil (most used, from coconut), hemp oil, olive oil, sunflower oil.
- Contains: CBD + all natural cannabinoids (CBG, CBN, CBC, traces of THC < 0.3 %)
- Advantage: demonstrated "entourage effect" (Russo 2011). Cannabinoids work in synergy.
- Disadvantage: trace THC can trigger a saliva test after heavy consumption.
- Recommended for: chronic pain, severe anxiety, deep sleep issues.
- Contains: CBD + other cannabinoids, BUT THC removed (< 0.01 %).
- Advantage: partial entourage effect + 0 % THC, so 0 saliva test risk.
- Disadvantage: slightly less powerful effect than full spectrum.
- Recommended for: regular drivers, competitive athletes, drug-tested workplaces.
- Contains: CBD only, no other cannabinoid.
- Advantage: ultra-precise dose, neutral taste, fully compatible with drug tests.
- Disadvantage: no entourage effect, less powerful at same dose.
- Recommended for: very targeted uses, or CBD discovery.
- Sublingual (drops under tongue): 25-35 % — the best
- Inhalation (vape): 35-45 % — fastest but short
- Oral (swallowed): 6-15 % — least effective, hepatic metabolism
- Topical (cream): 1-5 % — local use only
- Analysis date: less than 12 months old (otherwise the COA is no longer valid)
- Independent laboratory: name clearly stated
- CBD content: matches (± 10 %) the advertised percentage
- THC content: must be < 0.3 % (legal in France 2026)
- Heavy metals: lead, mercury, cadmium, arsenic — all < WHO limits
- Pesticides: must read "not detected" for all common molecules
- Residual solvents: if supercritical CO₂ extraction, must be "ND"
- Very common (>10 %): none
- Common (1-10 %): drowsiness at high dose, mild dry mouth, diarrhoea at very high dose
- Rare: drug interactions (see below)
- Very rare: elevated hepatic transaminases at doses > 1000 mg/day
- CYP3A4: metabolises ~50 % of medications
- CYP2C19: metabolises SSRI antidepressants, PPIs, some antiepileptics
- Warfarin (anticoagulant)
- Phenytoin, clobazam (antiepileptics)
- Cyclosporine (immunosuppressant)
- Some antidepressants (paroxetine, fluoxetine)
- Away from light (the bottle is amber for this reason)
- Temperature between 15 and 25 °C (not in fridge, not in sunlight)
- Cap tightly closed after each use
- Shelf life: 12 to 24 months after opening depending on brands
- Russo EB. "Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects" Br J Pharmacol. 2011.
- Birnbaum AK et al. "Food effect on pharmacokinetics of cannabidiol oral capsules..." Epilepsia. 2019.
- Iffland K, Grotenhermen F. "An update on safety and side effects of cannabidiol..." Cannabis Cannabinoid Res. 2017.
- Larsen C, Shahinas J. "Dosage, Efficacy and Safety of Cannabidiol Administration in Adults: A Systematic Review..." J Clin Med Res. 2020.
The concentration is expressed as a percentage. Example: a 10 % oil contains 1000 mg of CBD per 10 ml. Knowing a standard bottle contains 10 ml and a drop = ~0.05 ml = 5 mg of CBD at 10 %.
The 3 spectrum types
🌿 Full Spectrum
🌱 Broad Spectrum
💎 Pure CBD isolate (99 %+)
Which concentration to choose?
This is the most common question. Here's the reference table:
| Concentration | Dose per drop (10 ml) | Target user | |---|---|---| | 5 % (500 mg) | ~2.5 mg | Beginner, micro-dosing, sensitive | | 10 % (1000 mg) | ~5 mg | Regular use, moderate dose | | 15 % (1500 mg) | ~7.5 mg | Moderate anxiety, sleep | | 20 % (2000 mg) | ~10 mg | Chronic pain, severe anxiety | | 30 % (3000 mg) | ~15 mg | Intense pain, supervised use |
Golden rule: Start low, go slow. The universally validated principle.
Bioavailability: the key to effectiveness
Bioavailability is the percentage of CBD that actually reaches your bloodstream. It depends entirely on the route:
Pro tip: taking CBD oil with a fatty meal (olive oil, avocado, cheese) multiplies bioavailability 2-3×. A 2018 study (Birnbaum) showed 5× higher absorption when oil is taken with a fatty breakfast vs fasting.
How to read a COA (Certificate of Analysis)
A serious seller provides the COA of each batch. Here's what to verify:
Refuse any seller who cannot provide the COA. It's your only legal safeguard.
Possible side effects
According to systematic reviews (Iffland 2017, Larsen 2020):
At normal dose (< 100 mg/day), CBD is extremely well tolerated.
Drug interactions
CBD inhibits two key hepatic enzymes:
At-risk drugs:
If you are on chronic treatment: ask your doctor before starting CBD.
How to store CBD oil?
Signs the oil is oxidising: distinctly darker colour, rancid smell, bitter taste.
Our 2026 recommendation
For a hesitant beginner, here's our advice:
Start with a broad spectrum 10 % oil: partial entourage effect, 0 % THC (so 0 saliva test risk), reasonable price, easy dose adjustment.
After 2 weeks, either increase the concentration or stick with the same bottle. If effectiveness is insufficient after 3 weeks, move to full spectrum 15 %.