Hemp has been used for thousands of years and represents one of the oldest agricultural crops in the world. In fact, traces of hemp dating back to Neolithic times (around 6000 years ago) were found in central Asia,  suggesting that the plant existed well before it was introduced to North America by settlements in the early 17th century. 
Today, hemp is used extensively in a wide range of industries from textiles to paper and even food. However, it wasn’t always this way. The production and sale of hemp-based products were severely restricted and even banned under federal law for many years.
So, what is hemp? Why was it illegal in the US? And what exactlycan it be used for?
What is Hemp?
Hemp is a cultivated strain of the Cannabis sativaplant, specifically grown for industrial purposes. It’s one of the fastest growing plants known to humankind and can be used to make a variety of products including paper, rope, textiles, food and beverages, and other manufactured goods. 
Hemp is often mistaken for marijuana, with the two terms frequently used interchangeably. It’s understandable as both hemp and marijuana belong to the same genus of flowering plants, known as the Cannabaceaefamily, and both originate from the same species of cannabis, known as Cannabis sativa L. However, there are distinct differences in their genetic makeup, cultivation, and applications.
Firstly, marijuana is solely grown for recreational and medicinal use, while hemp is primarily grown for industrial purposes. According to the statutory definition, hemp must contain no more than 0.3% of delta-9-tetrahydrocannabinol (THC) on a dry weight basis.  As THC is the dominant psychotropic compound in cannabis, industrial hemp does not produce the “high” you would expect from marijuana, which is specially bred to contain higher concentrations of THC.
What is Hemp Used for?
Hemp has enormous environmental, economic and commercial potential. The global market for the plant currently consists of more than 25,000 products covering an extensive range of sub-markets. 
Hemp can be grown as a seed, fiber or even a dual-purpose crop. Recent market reports estimate that the gross value of hemp production per acre is approximately $12,500 from the stalks and $21,000 from seeds. 
Hemp seeds are primarily used for food and dietary products. They are a small seed which has a crisp outer shell and a creamy, soft center. Hemp seeds are extremely flexible – you can eat them raw on cereal or salads, ground them into a meal for cooking, and even turn them into plant-based milk.
Hemp seeds can also be used to make hemp seed oil (cold-pressed extract) which is high in anti-oxidants and fatty acids, although this does not contain any cannabinoids. Hemp seed oil can also be used to make a range of personal hygiene products including shampoo, soap, bath gels, and cosmetics.
What do Hemp Seeds do for Your Body?
Hemp seeds are a “superfood,” containing up to 20 amino acids (including nine essential amino acids), healthy fats (omega 3 and omega 6), and are a rich source of vitamins and minerals (e.g. Vitamin A, vitamin E, magnesium, zinc, iron). According to the USDA, 30 grams of hemp seeds (approximately one tablespoon) contains up to 9.47 grams of protein, higher than other plant sources including quinoa. 
Hemp Fiber (Bast)
Hemp fibers, commonly called bast, are the stringy bands that sit between the outer bark and wood stem, and run along the length of the stalk. They are the most usable part of the plant, with the primary fibers much longer (over 2 meters in length) than other plants such as bamboo.
Hemp fiber has a lot of different applications and is primarily used to make textiles (clothing, fabrics, household goods, etc.) and paper. It is one of the most durable fibers in the world and well known for its low cost and strength properties–which are up to 10 times stronger than cotton. 
Hemp Hurd (Shiv)
Hemp hurd, also known as the shiv, is the inner woody core of the stem. The hurd is primarily used for building materials such as fiberboard, insulation, cement blocks, and also as a substitute for fiberglass. For example, hemp concrete (a mixture of lime product and hemp hurds), is a bio-composite building material used as a lightweight insulation material.
Hemp Leaves and Flowers
Hemp is also harvested for its leaves and flowers–which are used to create hemp-derived CBD oil. As a popular (and legal) alternative to medical marijuana, hemp CBD oil provides many of the therapeutic benefits without the “high” (contains less than 0.3% THC concentration). Hemp CBD oil can help alleviate chronic pain, reduce the severity of seizures, improve inflammatory conditions such as rheumatoid arthritis and eczema, and manage anxiety.
Why Was Hemp Banned in the US?
As a common crop in the 1700s, American farmers were able to grow hemp, as it could be turned into a multitude of different products. However, the DEA’s (Drug Enforcement Administration) attitude towards hemp changed in the early 1900s, as hemp was grouped alongside its cannabis cousin, marijuana, due to its similar appearance. The Marihuana Tax Act of 1937 was then introduced, which limited the cultivation and sale of all cannabis varieties, contributing to the decline of the hemp industry.
While hemp was brought back for a brief period during WWII, it was then listed as a Scheduled I Drug in the Controlled Substances Act of 1970 (alongside heroin and LSD), making it, once again, illegal.
What is the Hemp Farm Bill?
However, the hemp industry has recently been revived. The 2018 Farm Bill (signed into law by President Trump on December 20th, 2018) reclassified hemp for commercial use, effectively removing it from the list of Controlled Substances. Hemp can now be grown and sold in the US as an agricultural product under federal law, although it also enables states and territories to establish their own regulatory structures on the production and sale within their borders.
The Farm Bill (also known as the Agricultural Improvement Act of 2018) identifies hemp by the level of THC concentration.  Any cannabis plant that contains more than 0.3% THC is considered marijuana–which is still illegal under federal law. This means that hemp-derived CBD oil is legal in all 50 states.
Can Hemp Make You Fail a Drug Test?
With the increased usage of hemp in food and dietary products, especially hemp-derived CBD oil, you might be wondering if it can cause you to fail a drug test. The short answer is no. As mentioned earlier, hemp is not cultivated from the marijuana plant and therefore doesn’t have the same psychoactive effects (the “high”) that you experience with marijuana. Hemp contains extremely low (or even non-existent) levels of THC, which are far below detectable amounts in standard drug tests.
In fact, one study analyzed the consumption of hemp food (commonly found in US retail stores) had little impact on an individual’s THC levels and was well below the limit for federal drug testing programs (15-ng/mL).  Marijuana, on the other hand, has a high THC concentration (up to approximately 35%). So, unless your consuming excessive amounts, it’s highly unlikely you will fail a drug test if you stick with government approved products. However, you can always look for CBD oil that contains zero THC just to be on the safe side.
The Future of The Hemp Industry
With recent legalization, the hemp industry is set to experience exponential growth. Hemp is a durable crop, with thousands of proven and potential applications from the construction industry all the way through to the medical field.