Cannabis exists in many varieties and sub-species. Cultivators and farmers have long been breeding different varieties with certain characteristics to create hybrids and specific strains.

Each cannabis strain has a different concentration of the cannabinoids tetrahydrocannabinol (THC), cannabidiol (CBD), as well as other compounds.

Producers grow the plants to have a certain look, taste, and effect on the user and brand them accordingly.

Currently, reports on the effects of different cannabis strains come predominantly from people’s experiences. Researchers are studying the effects of a variety of cannabis strains on a range of medical conditions.

What are cannabis strains?

All strains of cannabis derive from the Cannabaceae family of plants. Some experts consider that Cannabis indica and Cannabis sativa are the two main subspeciesTrusted Source, although some people think they are separate species.

To create a strain, cultivators select a variety of traits to produce the effects they want. This is a similar process to how breeders create particular characteristics in dogs.

People often describe cannabis strains as being indica, sativa, or hybrid. Hybrid refers to a strain created by combining both indica and sativa strains.

Many producers crossbreed cannabis plants to develop new strains with specific characteristics. Experts suggest that there are over 700 strainsTrusted Source of cannabis.

One of the most important characteristics of a cannabis strain is the THC content. Some rules exist on naming each strain, but many producers do not name their products according to these rules.

Despite these classifications, hybridization and crossbreedingTrusted Source has meant that people cannot tell exactly how much THC is in a particular plant by simply looking at its physical features.

Experts suggest it is impossible to guess the composition of a cannabis plant by looking at its height, branching, or leaf appearance.

The only way to know the chemical composition of a cannabis-derived product is to analyze it in a biochemical assay.

THC vs. CBD

So far, most researchTrusted Source into the medical benefits of cannabis has focused on THC and CBD.

Both THC and CBD are cannabinoids, they act differently in the body because they target different areas in the brain.

According to a 2020 articleTrusted Source, people who use products with a higher THC content may experience psychoactive effects, such as euphoria and a greater sensitivity to things such as color and taste. However, THC also can lead to anxiety and paranoia.

Learn more about what it feels like to be high here.

CBD, on the other hand, is non-intoxicating. Some people report mild physiological effects, such as reduced anxiety when using CBD.

Studies suggest CBD may help improve vomiting, nausea, pain, and offer neuroprotective effects on the brain.

Learn more about the effects of CBD here.

However, since CBD can affect mood, some expertsTrusted Source describe it as a non-intoxicating but psychoactive compound.

The Food and Drug Administration (FDA) have approvedTrusted Source some cannabis-related products including:

  • two synthetic THC medications for the treatment of anorexia associated with AIDS
  • another synthetic cannabis-related product for the treatment of nausea and vomiting associated with cancer treatment
  • cannabis-derived CBD for children 2 years and older who suffer from rare seizure disorders

Studies Trusted Sourceare ongoing to determine whether CBD has other physiological effects. Preliminary human data suggests CBD could benefit conditions, such as schizophrenia and even opioid addictionTrusted Source.

Learn more about the differences between CBD and THC here.

Sativa vs. Indica

The terms indica and sativa derive from the biolgical classification of these species, which is based on physical characteristics. Cannabis indica plants are shorter and have broad, dark green leaves. Cannabis sativa plants grow taller and develop thinner, pale green leaves.

In the past, people used these terms to differentiate the cannabis plants in terms of their effects and THC or CBD content. An article in Cannabis and Cannabinoid ResearchTrusted Source seems to dispel these claims.

Previously, people believed that Cannabis indica plants contained higher levels of CBD. As a result, cultivators and dispensaries marketed indica-derived strains as a product that would lead to a more ‘relaxed high’.

Conversely, Cannabis sativa-derived strains that contained higher levels of THC would provide a more energetic high.

Many experts caution against this generalization, noting that even if this classification scheme were true, there is no way to be sure of the accuracy of any strain name.

There is no third-party agency that validates which strain names belong to indica, sativa, or hybrid.

To know exactly what is in a cannabis product, the manufacturers must analyze the product in a biochemical assay.

It is easy to see why this topic continues to cause debate. Cannabis is a complex plant, and, as of right now, there seems no obvious or simple way to categorize the various strains by ‘effect on the user.’

Each person who tries a strain of cannabis may have a different experience.

For example, some people describe the effects of Cannabis indica-derived products as sedating. However, other components of cannabis can also cause sedation, as well as other psychoactive effects. Compounds include:

  • linalool
  • myrcene
  • limonene
  • alpha-pinene

These components are often absent in a description of a cannabis-derived product, which is why some experts suggest that manufacturers should abandon naming their products as sativa or indica. Using these names is misleading and far more complex than people once thought.

Learn more about the differences between indica, sativa, and hybrid plants, here.

Popular strains

Although a naming system for cannabis strains exists, manufacturers do not always follow the rules. Some producers name the strain according to the smell of the plant or its lineage; others, according to the plant’s color.

A study in the Journal of Headache and PainTrusted Source reported preferred cannabis strains among participants taking medical cannabis for pain.

Depending on its effects, researchers noted that some participants preferred certain strains over others. For example, the top three cannabis strains for insomniaTrusted Source or sleep disorder were:

  • Lemon sour diesel
  • OG shark
  • Skywalker

For mental health conditions, such as anxiety and depression, the preferred strains,Trusted Source included:

  • Jack Herer
  • Island sweet skunk
  • White widow

Please note that these examples of preferred cannabis strains come from user reports not from placebo-controlled clinical trials.

Note: Two people using the same cannabis strain may have different experiences.

Summary

Since cannabis is more readily available today than ever before, people need clear, accurate information on the effects of different cannabis strains for medical and recreational purposes.

Knowing the composition and physiological and mental effects of cannabis plants can help people and clinicians choose the most appropriate product.

Cannabis farmers crossbreed cannabis plants to create new strains that have different levels of THC, CBD, and many other physiologically active compounds.

Each plant may have different medicinal and recreational purposes.