Factors That Affect Your High: What Weed Research Measured

By Rick Smith / November 3, 2025

Lab bench with a tray of sample vials and three unlabeled jars of cannabis flower

Table of Contents

Quick answer: Many factors that affect your high are talked about, but only a few have been measured in the research cited here. University of Colorado Boulder studies found that strain type labels do not consistently match product chemistry, and that THC percent did not track with measured intoxication in a group of regular users. UGA Extension shows that lab reports themselves vary from lab to lab. This page describes those findings and how to read a lab report. It describes research, not advice.

What the Research Looked At

Lists of factors that affect your high often run to a dozen or more. Most of them are common talking points, not things the studies below measured. This guide keeps to three areas with opened university sources:

Chemistry and labels. Do strain names and indica, sativa or hybrid labels match what is in the product?
Product THC percent. Did higher THC products line up with higher measured intoxication in a study group?
Lab testing. How do lab reports differ, and what do their numbers mean?

Everything else is listed further down the page as not covered by the research cited here.

Chemotype and Strain Labels

A chemotype is a chemical profile, mainly the mix of cannabinoids and terpenes in a sample. A University of Colorado Boulder study sorted nearly 90,000 samples from six states by their cannabinoid and terpene make up. The researchers found that commercial labels “do not consistently align with the observed chemical diversity” of products.

The samples fell into three main terpene groups:

High in caryophyllene and limonene
High in myrcene and pinene
High in terpinolene and myrcene

Those groups did not neatly match the indica, sativa and hybrid labels. The authors wrote that a sample labeled indica is likely to have a terpene profile indistinguishable from samples labeled sativa or hybrid. Our page on indica and sativa plant differences covers what those words mean for the plant itself.

Strain names were mixed too. Some, like White Tahoe Cookies, were fairly consistent from product to product, while others, like Durban Poison, were “consistently inconsistent.” The study also notes that producers are free to name their product what they want. For more on how terpenes shape aroma, see our guide to terpenes and cannabis flavor.

THC Percent and Measured Intoxication

A 2020 University of Colorado Boulder study assessed 121 regular users. Half used flower at either 16 or 24 percent THC, and half used concentrates at either 70 or 90 percent THC. Concentrate users had much higher blood THC levels. Even so, lead author Cinnamon Bidwell said, “potency did not track with intoxication levels,” and the two groups were “similarly impaired” on the measures used.

What that study does and does not show:

It measured regular users, not new users.
It compared product groups, not individual people across many sessions.
It measured self reported intoxication plus balance and cognitive tests at set times.
It does not tell any one person what to expect.

The researchers raised tolerance in regular users as one possible reason for the result. Tolerance is a side topic here, and our tolerance breaks guide covers it.

Lab Reports and Testing Differences

UGA Extension explains that “depending on the lab, the information provided in lab reports will vary widely.” A few reasons for that stand out.

Units. Labs report cannabinoids as a percent or as milligrams per gram.
Weight basis. Results can be on a fresh weight (“as received”) or dry weight basis, and dry weight results read higher. The USDA requires official THC results on a dry weight basis.
Method. Gas chromatography (GC) reports cannabinoids in their neutral forms, while high pressure liquid chromatography (HPLC) reports both acid and neutral forms.
Limits. Reports can list a limit of detection, a limit of quantitation and a measure of uncertainty.

So two reports for the same strain name can look different for reasons that have nothing to do with the plant.

Factors Not Covered by the Research Cited Here

These topics come up often, but the sources on this page did not measure them, so this guide does not make claims about them:

Consumption method
Amount used
Food, body weight and metabolism
Experience level
Mood, hydration, time of day and sleep
Set and setting

Set and setting means a person’s mindset and surroundings, and it is discussed widely. Combining cannabis with other substances is a separate topic, covered on our page about mixing cannabis with other drugs.

How to Read a Cannabis Lab Report

Match the report to the product. Check that the sample name, batch or lot number and lab number match the package.
Check the test date. UGA notes that reports include dates. An old report may not reflect the product in hand.
Find the units. Note whether results are in percent or mg/g before comparing two reports.
Find the weight basis. Check whether results are fresh weight or dry weight.
Check the method. HPLC reports list acid forms such as THCA as well as neutral forms, while GC reports list neutral forms only.
Read the limits. Look for the limit of detection, the limit of quantitation and the measure of uncertainty.
Look for a terpene panel. If one is listed, compare its main terpenes with the three groups in the CU Boulder study.
Compare like with like. Only compare reports that use the same units, weight basis and method.

Troubleshooting

The label type does not match the terpene report. This is common. The CU Boulder study found that indica, sativa and hybrid labels do not consistently match terpene groups. Go by the report.

Two lab results for the same strain differ. Check units, weight basis, method and test date first. Then check the batch. Same named products can differ.

One report lists THCA and another does not. The labs may have used different methods. HPLC lists acid forms, while GC lists neutral forms.

The report has no terpene panel. Not every lab tests terpenes. Without a panel, you cannot place the product in a terpene group.

The test date is old. Ask for a newer report or read the numbers as a past snapshot.

The strain name means something different at each shop. Producers are free to name products, so compare reports, not names.

Frequently Asked Questions

Why can the same strain name show different results on a lab report?

There is no standard for strain names, and producers are free to name their products. A University of Colorado Boulder study found that some strain names were consistent while others were “consistently inconsistent.” Labs also report results differently, according to UGA Extension.

Do strain names match what lab tests find?

Not reliably. A University of Colorado Boulder study of nearly 90,000 samples found that commercial labels do not consistently align with the observed chemical diversity of products, and that terpene groups did not match indica, sativa and hybrid labels.

What did CU Boulder find about THC percent and measured intoxication?

In a 2020 study of 121 regular users, concentrate users had much higher blood THC levels than flower users. The lead author said potency did not track with intoxication levels on the measures used.

How do you read a cannabis lab report?

Match the sample and batch to the package, check the test date, then note the units, the weight basis and the testing method. UGA Extension explains that HPLC reports list acid and neutral forms while GC lists neutral forms, and that reports can include detection limits and a measure of uncertainty.

What is a chemotype?

A chemotype is a chemical profile, mainly the mix of cannabinoids and terpenes in a sample. A University of Colorado Boulder study grouped samples into three main terpene groups that did not match the indica, sativa and hybrid labels.