THC isn’t everything. Our friends at Phyre do a wonderful job of explaining why in their recent blog post.

Introduction

Imagine walking into a liquor store in search of the perfect bottle of alcohol. “Which one’s the highest proof?” you ask the clerk, scouring each label for the alcohol content of each.

After carefully reading each label, you walk out with several bottles of 190 proof, 95% alcohol, “might-as-well-be-drinking-battery-acid” Everclear.

Seems unlikely, right? Even ludicrous?

Unfortunately, this scenario is not unlike what’s happening at cannabis retail shops and dispensaries across the (legal) nation: Many consumers are walking in and demanding the highest THC content available, often without realizing that the THC percentage of any particular flower is only one indicator of the resulting high.

You don’t choose your wine or liquor based on alcohol content — so why would you choose your cannabis based on THC percentage?

No cannabis connoisseur I know chooses her weed based primarily on THC content, and here’s why: First, this method overlooks a multitude of factors that contribute to the ultimate effect of any given flower. (Think about the wide array of factors that contribute to the effects of a glass of wine, for example.) Second, it turns out that THC isn’t necessarily a reliable indicator of potency in the first place.

Yes, you heard me right: Perhaps the biggest myth about THC is that it has ever been a reliable indicator of potency in the first place.

“The most potent strain I’ve smoked,” said Dr. Donald Land during a Green Flower Media talk, “was in Jamaica and it was 12% THC.”

Phyre co-founder Stefani Malott has had a similar experience:

“This OG Kush is one of my favorite strains,” she explains. “It gives me the giggles, melts away my pain, and it just makes me feel so happy. And at 14%, it hits me a lot harder than most strains testing in the mid to high twenties.”

Maybe you’ve noticed this before, too: lower-testing flower might have hit you harder than expected, or perhaps higher-testing flower has sometimes turned out to be — ahem, slightly underwhelming in effect. Whatever the case, you can almost certainly relate to holding a preference for the effects of a particular strain over those of another.

What causes these kinds of differences among cannabis varieties? If THC content alone cannot reliably explain variations in effect and potency among strains, what can? And if not based primarily on THC content, how should we choose our weed?

We’re glad you asked.

Cracking the THC Code

David Mapes, founder and researcher at Epsilon Research in Sacramento, California, has been researching the therapeutic use of whole plant cannabis for years.

“You must remember that cannabis is not just about cannabinoids [such as THC],” Mapes states. “It also contains numerous types of constituents that are responsible for the various ways that those cannabinoids will act and how the body will react.”

In other words, like your Facebook relationship status, it’s complicated. With over 430 unique compounds identified in the cannabis plant, the way in which the various components interact to create a range of effects and potency levels is complex.

As a simplified analogy, you might think of THC as just one of many colors in an artist’s watercolor palette:

Blue plus yellow = green.

Blue plus red = purple.

Even when both combinations contain the exact same amount of blue, the end result is entirely different.

Likewise, in the context of cannabis, two plants with the exact same THC percentage can produce very different effects and potency levels depending upon the specific combination of additional compounds present in the plant.

It’s not the THC content that matters most, but how the THC combines with other compounds in the plant to create unique synergistic effects of varying magnitude and effect.

For example, you may already know that CBD has been found to soften the effect of THC — so much so that for most people a 1:1 ratio of THC:CBD results in a very mild psychoactive effect, if any at all. In comparison, a flower with the same THC content but, say, one-twentieth the amount of CBD would undoubtedly result in a much stronger high for the user.

That’s just one illustration of how the properties of different compounds can interact to create a unique synergistic profile. But in addition to cannabinoids like THC and CBD, what other types of compounds play a central role in determining the effect of any given flower?

If you guessed “terpenes,” you guessed right.

Terpenes are a class of organic hydrocarbons responsible for giving cannabis its glorious range of aromas, from fruity to skunky to earthy and beyond. It turns out that terpenes do much more than provide a pleasing aroma, however: In large part, they are responsible for a vast range of effects that cannot be explained by THC or other cannabinoids alone.

What’s the difference between an Indica and a Sativa? Why is it that two strains with the same THC content can affect an individual so differently? Terpenes, it turns out, have a lot to do with this.

What Combination of Terpenes is Right for You?

Just like a fine whiskey or wine, cannabis comes with many flavors and subtleties, many of which are deeply influenced by the plant’s terpene content. So when selecting your cannabis, it’s important to consider the effects you’re seeking.

Are you using cannabis to relax and unwind? To energize? To aid your sleep, ease your pain, or calm your anxiety? Do you like a heady high or a body high? A lighter or a heavier effect? Do you have any medical concerns you’d like to address using cannabis?

As a starting point for helping you determine your personalized terpene profile, consider the effects of five of the most common terpenes listed below.

Table 1.1: 5 Common Terpenes and Their Respective Effects