An interesting facet of today’s drug use culture is the notion that marijuana is many times more powerful today in terms of potency than it was back in the 1960s and 1970s. One can peruse the Internet and see reports that marijuana sold today is 100-200 times more potent than marijuana back in 1970s. Is this true?

Empirical Research on the Topic

Increasing Strength of Marijuana
A very important breakthrough study occurred in 2013 and was reported in the journal Drug Testing and Analysis. This report involved data from the Potency Monitoring Program, which is a program funded by the National Institute on Drug Abuse. The study focused on drug seizures by the United States Drug Enforcement Administration. The data contained information from over 46,000 drug seizures occurring between the 1970s and 2010. Several different metrics were used to determine the potency of the marijuana seized in these incidents over this time period.

Based on the results of the study, there are several conclusions that can be drawn:

  • First, it was determined that the marijuana being used today is more potent than the marijuana that was available in the 1970s.
  • The average percentage of delta-9-tetrahydrocannabinol (THC) which is the major psychoactive ingredient in marijuana increased during this time from less than 1 percent in the 1970s to 10-11 percent in the late 2000s.
  • The THC content was relatively low in the 1970s, rose dramatically in the 1980s, and continued to rise in the 1990s. Its potency in marijuana spiked up and down in the 2000s.
  • Other ingredients in marijuana appear to have either decreased in potency or not changed significantly. For example, a recent analysis that was just presented at the annual meeting of the American Chemical Society has indicated that while THC potency appears to be rising, the cannabidiol content, a component of marijuana that is believed to be reasonable for its suggested therapeutic properties, appears to be decreasing.
  • The researchers also note that when marijuana was smuggled from other countries into the United States in the 1970s, a lower-potency type of marijuana was common. As marijuana became more of a domestic crop, and individuals had access to fresh or and better strains of marijuana in the United States, the potency seems to have increased.
  • The potency of THC and cannabis is related to its freshness and the age of the plants, which also seem to account for some of the changes in marijuana potency.
  • The level of contaminants in marijuana has appeared to increase. These can include microbes, heavy metals, and other substances.

Thus, the notion that marijuana is 100-200 times more potent today than it was in a 1970s is an urban myth; however, there is obviously a dramatic increase in potency that probably makes it seem like it is far more potent today than it was in the 1970s. Because it is fresher and more potent, it may seem to many long-term users to be hundreds of times more potent. In reality, it is more potent in terms of its THC content, but the claims of marijuana today being hundreds of times more potent than marijuana in the 1960s and 1970s are not substantiated.

Edible Forms of Marijuana and Dabs

Edible Forms of Marijuana and Dabs
Many people think that marijuana is essentially harmless; however, this is not true. For example, the Drug Abuse Warning Network, a division of the National Institute of Mental Health, continues to report that increasing numbers of people seek emergency department treatment for marijuana-related issues (well into the hundreds of thousands of cases). High doses of THC can lead to a number of issues, including problems with the immune system, memory issues, and even severe psychotic reactions. The effects of marijuana are obviously dependent on how it is taken and metabolized in the body.

“Dabs” or taking edible forms of marijuana often involve the use of other chemicals and may increase the potency of the THC even higher. The process of taking dabs involves first concentrating the THC in marijuana by various means, vaporizing it, and then inhaling it. This leads to inhaling almost pure forms of THC, and the potency is increased dramatically.


The empirical research indicates that the potency of THC in marijuana has increased dramatically from the marijuana that was available in the 1960s and 1970s. However, reports that marijuana is hundreds of times more potent today are not well-founded. The increased potency of THC in marijuana also appears to be associated with a decreased potency of other substances that may actually be responsible for some of the therapeutic effects that marijuana may produce. Using marijuana in highly concentrated forms increases the risk of experiencing detrimental side effects of THC.