Evidence-graded reference • Reviewed August 24, 2026

The science behind your high

Cannabis chemistry is genuinely interesting and routinely oversold. This page keeps the two apart: what a laboratory measured, what controlled human research has actually shown, and what is still a hypothesis wearing a lab coat.

Start with the six families How we grade evidence
Terpene clusters behind the families
6
Evidence-graded terpene profiles
26
Controlled terpene + THC human trials
2

How to read this page

Seven labels keep unlike evidence apart

Most cannabis claims online come from cells, animals, essential oils, or pharmaceutical formulations — not from people using cannabis products. Those studies generate hypotheses; they cannot show that the much smaller amount in a jar produces the same result. Every claim below carries the label for its strongest relevant evidence. The label describes the claim, not the quality of the molecule.

  • Regulator-approved medicine

    A purified compound reviewed and approved by a drug regulator for a named condition. It says nothing about cannabis products generally.

  • Controlled human evidence

    Randomized or otherwise controlled research in people. Dose, route, and sample size still limit how far it generalizes.

  • Other human evidence

    Observational, pilot, or safety evidence in people, without the experimental control of a randomized design.

  • Animal research only

    A biological signal in animals. Useful for generating hypotheses, not for predicting a human cannabis experience.

  • Laboratory research only

    Cells, receptors, or isolated systems. Establishes mechanism at concentrations a product may never reach.

  • Chemistry and measurement

    Identity, occurrence, biosynthesis, or analytical detection. A measurement, not an effect claim.

  • Evidence insufficient

    The available evidence is indirect, mixed, or too limited to support a responsible conclusion.

Classification

The six High Families, and what they rest on

Sativa, indica, and hybrid describe how a plant grows. They are a weak guide to what is in it: the 2025 German chemovar study found no statistical correlation between terpene profile and sativa/indica genetics (p > 0.05). So we group strains the way a lab does — by measured terpene profile. Our six families are patterned on the six terpene clusters that study found across 140 medicinal flowers.

From the study

The numbers are measurements

  • 140 flowers analysed by GC-MS, grouped by k-means clustering
  • Six distinct clusters covering all 140 classified flowers
  • Nine terpenes explain 86% of the variation between profiles
  • Every mg/g, THC, and CBD figure on the cards below is theirs

From us

The names and the feel are ours

  • The paper labels its clusters “Cluster No. 1” through “6” and names none of them
  • Uplifting, Energetic, Relaxing, Balancing, Relieving and Entourage are our names
  • So is every effect and time-of-day suggestion attached to them
  • The authors say medical differences “has to be investigated in clinical trials”

A quiet terpene profile is not a weak one. Every cluster in that study averaged between 18% and 26% THC — judge strength by the cannabinoid figure on the label, never by how little the jar smells.

Browse all six families Read our study deep dive

Aroma chemistry

Terpenes, graded by what we actually know

Terpenes are part of what a cannabis sample smells like, and part of what a lab can count. They are not a promise about how you will feel. Flip any card to see the measured side and the unknown side of the same compound.

Laboratory research only

Myrcene

β-Myrcene • MER-seen

Aroma vocabulary
earthy · musky · herbal
Chemical class
Acyclic monoterpene

Controlled human evidence

Limonene

D-Limonene • LIM-oh-neen

Aroma vocabulary
citrus peel · lemon · orange
Chemical class
Cyclic monoterpene

Controlled human evidence

Alpha-Pinene

α-Pinene • AL-fuh PIE-neen

Aroma vocabulary
pine needle · resin · fresh herbs
Chemical class
Bicyclic monoterpene

Animal research only

Linalool

Linalool • lin-ah-LOOL

Aroma vocabulary
floral · lavender-like · sweet
Chemical class
Acyclic monoterpene alcohol

Laboratory research only

Beta-Caryophyllene

β-Caryophyllene • BAY-tuh carry-OFF-ill-een

Aroma vocabulary
black pepper · spice · wood
Chemical class
Bicyclic sesquiterpene

Laboratory research only

Alpha-Humulene

α-Humulene • AL-fuh HYOO-muh-leen

Aroma vocabulary
hops · wood · earth
Chemical class
Monocyclic sesquiterpene

Animal research only

Terpinolene

Terpinolene • ter-PIN-oh-leen

Aroma vocabulary
pine · floral · citrus
Chemical class
Cyclic monoterpene

Chemistry and measurement

Ocimene

Ocimene isomer mixture • OH-sih-meen

Aroma vocabulary
sweet herbs · green · floral
Chemical class
Acyclic monoterpene

Showing the 8 core profiles from our 26-profile library. Aroma also comes from volatile sulfur compounds, esters, and aldehydes that no terpene panel reports — which is part of why two jars with matching terpene numbers can smell nothing alike.

Browse all 26 terpene profiles How to read a lab report

The active compounds

Cannabinoids, and how far the research goes

One cannabis compound has a regulator-approved medicine behind it. Most have receptor assays and rodents. Each card leads with which of those it is, then says what the evidence showed and what it leaves open.

  • Controlled human evidence

    THC

    Δ9-Tetrahydrocannabinol

    psychoactive
    Typical range
    10-30%
    Bioavailability — smoked / vaped / eaten
    10-35% · 30-40% · 4-20%

    Primary psychoactive cannabinoid in cannabis. THC binds strongly to CB1 receptors in the brain, producing euphoria, altered perception, and appetite stimulation. Edibles convert THC to 11-OH-THC, which is more potent and produces stronger body effects.

    What the evidence shows

    THC is a CB1 agonist and its acute effects are the best characterised in cannabis — controlled human dosing reliably reproduces euphoria, altered time perception, memory impairment, and raised heart rate. First-pass metabolism converts oral THC to 11-OH-THC, which is why edibles land differently from inhalation at the same labelled dose.

    What it does not establish

    A THC percentage predicts neither the dose you absorb nor the experience you get: route, inhalation depth, tolerance, and setting all move the result. Claims that a specific terpene reliably softens THC anxiety are not settled — the one controlled trial to show any such signal did so only at its highest combination, and a comparable alpha-pinene trial was negative.

    Effects attributed to it

    • Euphoria
    • Pain relief
    • Appetite stimulation
    • Altered perception
    • Relaxation

    Receptors and targets

    • CB1 (primary)
    • CB2 (secondary)

    Studied for — not proven for

    • Chronic pain
    • Nausea/vomiting
    • Appetite stimulation
    • PTSD
    • Insomnia

    Sources Spindle 2024 — Vaporized D-limonene selectively mitigates the acute anxiogenic effects of Δ9-tetrahydrocannabinol in healthy adults who intermittently use cannabis (opens in new tab) Zamarripa 2025 — The Individual and Interactive Effects of Alpha-Pinene and Delta-9-Tetrahydrocannabinol in Healthy Adults (opens in new tab)

  • Regulator-approved medicine

    CBD

    Cannabidiol

    non-psychoactive
    Typical range
    0.5-20%
    Bioavailability — smoked / vaped / eaten
    11-45% · 40-50% · 6-15%

    Non-psychoactive cannabinoid, and the only one behind an approved medicine. CBD modulates cannabinoid receptor signaling indirectly and interacts with serotonin and TRPV receptors; anti-anxiety, anti-inflammatory, and neuroprotective effects are the targets of that research rather than settled outcomes.

    What the evidence shows

    CBD is the one cannabis compound with a regulator-approved medicine behind it. Epidiolex, a purified CBD oral solution, is FDA-approved for seizures associated with Lennox-Gastaut syndrome, Dravet syndrome, and tuberous sclerosis complex in patients one year and older. It does not produce intoxication.

    What it does not establish

    Epidiolex is a pharmaceutical-grade isolate at prescription doses under medical supervision. That says nothing about whether a CBD product off a shelf helps anxiety, sleep, pain, or inflammation — those uses are far less settled, and consumer doses are typically much lower.

    Effects attributed to it

    • Anti-anxiety
    • Anti-inflammatory
    • Neuroprotective
    • Anti-seizure
    • Muscle relaxation

    Receptors and targets

    • 5-HT1A
    • TRPV1
    • GPR55
    • Indirect CB1/CB2 modulation

    Studied for — not proven for

    • Epilepsy
    • Anxiety disorders
    • Inflammation
    • Chronic pain
    • Neuroprotection

    Source FDA label 2018 — EPIDIOLEX (cannabidiol) oral solution — prescribing information (opens in new tab)

  • Controlled human evidence

    CBG

    Cannabigerol

    non-psychoactive
    Typical range
    <1% (precursor to other cannabinoids)
    Bioavailability — smoked / vaped / eaten
    ~15-30% · ~30-40% · ~5-15%

    The "mother" or "stem cell" cannabinoid from which THC, CBD, and CBC are synthesized. CBG is usually present in low amounts (<1%) and is an active research target, though most of the therapeutic work so far is preclinical.

    What the evidence shows

    A double-blind, placebo-controlled crossover field trial gave 34 healthy adults 20 mg of hemp-derived CBG. Participants reported lower anxiety and stress than on placebo, with no intoxication and no measured impairment of motor function or cognition.

    What it does not establish

    One pilot in 34 healthy adults, self-administered outside a laboratory, is a starting point rather than a finding. Antibacterial, neuroprotective, and glaucoma claims for CBG remain preclinical, and flower typically carries under 1% CBG — far below a 20 mg isolate dose.

    Effects attributed to it

    • Memory enhancement
    • Anxiety reduction
    • Antibacterial
    • Anti-inflammatory
    • Neuroprotective

    Receptors and targets

    • CB1 (partial)
    • CB2 (partial)
    • α2-adrenoceptor
    • TRPV1

    Studied for — not proven for

    • Glaucoma
    • IBD
    • Huntington's disease
    • Bacterial infections
    • Bladder dysfunction

    Source Cuttler 2024 — Acute effects of cannabigerol on anxiety, stress, and mood: a double-blind, placebo-controlled, crossover, field trial (opens in new tab)

  • Evidence insufficient

    CBN

    Cannabinol

    mildly psychoactive
    Typical range
    <1% (increases with age/oxidation)
    Bioavailability — smoked / vaped / eaten
    ~10-25% · ~20-35% · ~5-12%

    Created when THC ages or is exposed to heat/light. CBN is about 10 times less potent at CB1 receptors than THC, producing minimal intoxication but notable sedative properties.

    What the evidence shows

    CBN forms as THC oxidises with age, heat, and light. It binds CB1 far more weakly than THC — roughly a tenth as potent — which is consistent with its mild effects. The sedative signal comes mostly from rodent work.

    What it does not establish

    The "aged cannabis makes you sleepy because of CBN" story runs well ahead of the evidence. Controlled human trials of CBN as a sleep aid remain sparse and small, and the amount in ordinary flower is low. Treat CBN sleep products as unproven.

    Effects attributed to it

    • Sedative
    • Sleep aid
    • Pain relief
    • Appetite stimulation
    • Anti-inflammatory

    Receptors and targets

    • CB1 (weak)
    • CB2 (moderate)

    Studied for — not proven for

    • Insomnia
    • Pain
    • Bacterial infections
    • Appetite stimulation

  • Laboratory research only

    CBC

    Cannabichromene

    non-psychoactive
    Typical range
    0.05-0.3%
    Bioavailability — smoked / vaped / eaten
    ~15-30% · ~25-40% · ~5-15%

    Non-psychoactive cannabinoid synthesized from CBGA. CBC selectively activates CB2 receptors with higher efficacy than THC, which produces anti-inflammatory and analgesic effects in preclinical models without psychotropic side-effects.

    What the evidence shows

    In cell and rodent models CBC activates CB2 receptors with high efficacy and reduces inflammatory signalling. Because CB2 sits mainly on immune cells rather than in the brain, it does so without intoxication.

    What it does not establish

    No controlled human trial establishes that CBC relieves pain, inflammation, or low mood at the amounts found in cannabis products, which are usually well under 0.5%.

    Effects attributed to it

    • Anti-inflammatory
    • Analgesic
    • Mood enhancement
    • Neurogenesis
    • Antidepressant

    Receptors and targets

    • CB2 (selective, high efficacy)
    • TRPV1
    • TRPA1

    Studied for — not proven for

    • Depression
    • Pain
    • Inflammation
    • Acne
    • Cancer (preclinical)

  • Controlled human evidence

    THCV

    Tetrahydrocannabivarin

    psychoactive
    Typical range
    <1% (higher in some African strains)
    Bioavailability — smoked / vaped / eaten
    ~10-30% · ~25-40% · ~5-15%

    A homologue of THC with a shorter side chain. THCV has minimal psychoactivity at typical doses and displays unique metabolic effects including appetite suppression and enhanced energy metabolism.

    What the evidence shows

    A randomized, double-blind, placebo-controlled pilot in 62 people with type 2 diabetes tested 5 mg THCV twice daily for 13 weeks. THCV lowered fasting plasma glucose and improved several markers of pancreatic beta-cell function relative to placebo.

    What it does not establish

    That is one 13-week pilot at a fixed isolate dose in people with diabetes, not a result about smoking a high-THCV cultivar. Appetite suppression and the energising reputation rest largely on CB1 antagonism in preclinical work, and THCV is dose-dependent — it shifts toward agonism at higher doses.

    Effects attributed to it

    • Appetite suppressant
    • Energy boost
    • Bone growth
    • Glycemic control
    • Neuroprotective

    Receptors and targets

    • CB1 (antagonist)
    • CB2 (partial agonist)

    Studied for — not proven for

    • Diabetes
    • Obesity
    • Parkinson's disease
    • Metabolic syndrome
    • Bone disorders

    Source Jadoon 2016 — Efficacy and Safety of Cannabidiol and Tetrahydrocannabivarin on Glycemic and Lipid Parameters in Patients With Type 2 Diabetes (opens in new tab)

The hypothesis

The entourage effect, with the inconvenient results included

The entourage effect is the hypothesis that a mixture of cannabis compounds can act differently from an isolated compound. It is a reasonable question, not an established benefit: a combination can produce a positive, a negative, or no detectable interaction, and a label will not tell you which.

The hypothesis does a lot of commercial work — "full spectrum", "whole plant", and terpene-forward marketing all lean on it. So here is every strand of evidence we would cite, including the strands that cut against it.

None of this makes full-spectrum products worse than isolates. It means the reason to prefer one is preference and experience, not a demonstrated synergy — and that a product promising a specific terpene will change your high is promising more than anyone has shown.

Route and timing

How you take it changes the dose you get

The same milligrams behave differently depending on how they reach your bloodstream. Inhalation peaks fast and clears fast. Anything swallowed passes through the liver first, where THC becomes 11-OH-THC — which is why edibles land later, harder, and for much longer. Expand any method for onset, duration, and how much actually gets absorbed.

Onset
Peak
Duration

Your side of the equation

The endocannabinoid system

Cannabis works because your body already runs a signalling system it can plug into. You produce your own cannabinoids — anandamide and 2-AG — that help regulate mood, memory, appetite, pain, and immune response. THC is close enough in shape to hijack part of it.

Where the high happens

CB1 receptors

Concentrated in the brain and central nervous system — the most abundant G-protein-coupled receptor in the mammalian brain, dense in cortical, amygdala, and basal ganglia regions. THC binding here produces the intoxication, the altered time sense, and the short-term memory effects. It is also why tolerance builds: sustained use reduces how many of these are available.

Where it does not

CB2 receptors

Found mainly on immune cells and in peripheral tissue, and upregulated on microglia during inflammation. Compounds acting here — CBC and beta-caryophyllene among them — do so without intoxication, which is what makes CB2 the interesting target for anti-inflammatory research. Interesting is not the same as proven.

The endocannabinoid system was only identified in the early 1990s, which is a large part of why the research base here is thinner than the marketing suggests.

Finding your level

Tolerance and dose

Other human evidence

What a tolerance break does

Daily cannabis use downregulates CB1 receptors in cortical brain regions — the receptors are still there, but fewer are available for THC to bind. PET imaging shows that reversing within weeks of stopping. The percentages below are receptor recovery, not a measure of how high you will feel.

  1. 2 days

    Receptor availability starts climbing almost immediately

    20-40%

    A short break already moves the needle — most of the tolerance you built is not permanent

  2. 1-2 weeks

    Recovery continues over the following weeks

    50-70%

    The usual point where a returning dose feels noticeably stronger

  3. 4 weeks

    Availability no longer differs from people who do not use

    90-100%

    Full measured reset — go back at a much lower dose than you left off at

Evidence

PET imaging found chronic daily cannabis smokers had roughly 20% lower cortical CB1 receptor availability than non-smokers, returning to normal after about four weeks of monitored abstinence (Hirvonen et al., Molecular Psychiatry 2012). A later PET study in cannabis-dependent men found availability had already begun rising after just two days of abstinence (D'Souza et al., 2016).

Convention, not a clinical scale

Dose bands for edibles

Bands describe ingested THC for someone with little or no tolerance. Individual response varies severalfold, so treat them as a starting point, not a prescription.

  • 1-2.5mg THC

    Subtle effects, functional for daytime use

    Best for: Beginners, daily function, microdosing protocols

  • 2.5-5mg THC

    Mild euphoria and relaxation

    Best for: Beginners, social use, gentle relief

  • 5-10mg THC

    Noticeable psychoactive effects and impairment

    Best for: Intermediate users, evening use, pain relief

  • 10-20mg+ THC

    Strong effects and significant impairment

    Best for: Experienced users only, high tolerance, severe symptoms

Start low and wait the full two hours before taking more. Onset for anything swallowed is 30–90 minutes, and the most common bad experience is a second dose taken before the first one arrived. You can always take more; you cannot take less.

Evidence base

Everything this page rests on

The primary studies, analytical references, and regulatory documents behind the claims above, in the order you meet them. Individual terpene profiles carry their own compound-specific sources.

  1. Chemistry and measurement

    Classification of Cannabis Strains Based on their Chemical Fingerprint — A Broad Analysis of Chemovars in the German Market (opens in new tab)

    Cannabis and Cannabinoid Research 10(3):409-419 • 2025

  2. Chemistry and measurement

    The phytochemical diversity of commercial Cannabis in the United States (opens in new tab)

    PLOS ONE • 2022

  3. Chemistry and measurement

    Terpenes in Cannabis sativa — From plant genome to humans (opens in new tab)

    Plant Science • 2019

  4. Controlled human evidence

    Vaporized D-limonene selectively mitigates the acute anxiogenic effects of Δ9-tetrahydrocannabinol in healthy adults who intermittently use cannabis (opens in new tab)

    Drug and Alcohol Dependence • 2024

  5. Controlled human evidence

    The Individual and Interactive Effects of Alpha-Pinene and Delta-9-Tetrahydrocannabinol in Healthy Adults (opens in new tab)

    Medical Cannabis and Cannabinoids • 2025

  6. Laboratory research only

    Terpenoids From Cannabis Do Not Mediate an Entourage Effect by Acting at Cannabinoid Receptors (opens in new tab)

    Frontiers in Pharmacology • 2020

  7. Regulator-approved medicine

    EPIDIOLEX (cannabidiol) oral solution — prescribing information (opens in new tab)

    U.S. Food and Drug Administration • 2018

  8. Controlled human evidence

    Acute effects of cannabigerol on anxiety, stress, and mood: a double-blind, placebo-controlled, crossover, field trial (opens in new tab)

    Scientific Reports 14:16163 • 2024

  9. Controlled human evidence

    Efficacy and Safety of Cannabidiol and Tetrahydrocannabivarin on Glycemic and Lipid Parameters in Patients With Type 2 Diabetes (opens in new tab)

    Diabetes Care 39(10):1777-1786 • 2016

  10. Other human evidence

    Reversible and regionally selective downregulation of brain cannabinoid CB1 receptors in chronic daily cannabis smokers (opens in new tab)

    Molecular Psychiatry 17(6):642-649 • 2012

  11. Other human evidence

    Rapid Changes in Cannabinoid 1 Receptor Availability in Cannabis-Dependent Male Subjects After Abstinence From Cannabis (opens in new tab)

    Biological Psychiatry: Cognitive Neuroscience and Neuroimaging 1(1):60-67 • 2016

  12. Chemistry and measurement

    Office of Cannabis Management Testing Limits (opens in new tab)

    New York State Office of Cannabis Management • 2026

Common questions

Cannabis science questions

The questions we get asked most, answered without overselling the evidence.

Is the entourage effect proven?

No. It remains a hypothesis. The two controlled human trials of a single terpene alongside THC disagree: a small limonene study found lower anxiety ratings only at its highest combination, while a comparable alpha-pinene study found no effect at all. Receptor assays have repeatedly failed to find terpenes acting at CB1 or CB2. A combination can help, hurt, or do nothing, and a label will not tell you which.

Can a terpene profile predict how a strain will feel?

Not reliably. A certificate of analysis describes the sample that was tested, not your response to it. Cannabinoid dose, route, tolerance, setting, batch variation, and volatile compounds outside the reported terpene panel all move the outcome.

What are the High Families, and how do they relate to sativa and indica?

They are six categories patterned on the six terpene clusters found in the 2025 German chemovar study of 140 medicinal flowers. That study found no statistical correlation between terpene profile and sativa/indica genetics (p > 0.05), which is why we group by measured chemistry instead. The cluster measurements are the study’s; the family names, and every effect we attach to them, are ours.

Does a higher THC percentage mean a stronger experience?

Not directly. A label percentage tells you what was in the tested sample, not the dose you absorb — route, inhalation depth, and tolerance change that severalfold. It is a better guide to strength than aroma, though: a quiet terpene profile is not a weak one, and every cluster in the German study averaged between 18% and 26% THC.

How long does a tolerance break take to work?

PET imaging shows CB1 receptor availability starting to recover within about two days of stopping, and no longer differing from non-users after roughly four weeks. Those percentages measure receptors, not how high you feel — but they are why returning after a break at your old dose is a bad idea.

Why does the same strain affect people differently?

Batch chemistry varies between harvests of the same cultivar, and so do you: tolerance, metabolism, body composition, endocannabinoid signalling, setting, and expectation all change the result. Two jars with the same name are not the same product, and two people with the same jar are not running the same experiment.

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