HOT TOPICSUpdated November : 16 : 2004 Key Points

Cannabis contains more than 400 chemicals. The main psychoactive ingredient is delta-9-tetrahydrocannabinol, or 'THC'

Cannabis contains more tar than tobacco, and has a higher concentration of carcinogens (cancer-causing agents)

Cannabis became a controlled substance in Britain in 1928

44% of 16 to 29 year-olds have tried cannabis at some point in their lives. Half of them have used it in the last year

In 1998, 76% of people arrested for drugs offences in Britain were charged with possession of cannabis

Smoking marijuana is more popular in America than surfing the Internet

Ganja, marijuana, weed, puff, smoke, pot, herb, dope, resin, grass, there are hundreds of names to describe it. But, call it what you want, the recreational use of cannabis is still illegal in Britain, although that hasn't stopped around half of all young people trying it.

Smoking a joint Is cannabis harmless?

Cannabis is less addictive than amphetamines, tobacco or alcohol, and does less harm to the body It may be psychologically addictive. Heavy users can display aggressive impulses if their supply suddenly stops, a side effect similar to that of anabolic steroids A government report found that high use of cannabis isn't associated with major health or sociological problems, unlike other harder drugs Cannabis may be a 'gateway' drug to more harmful substances like heroin and cocaine Its effects are beneficial to sufferers of various medical conditions, including cancer, HIV, multiple sclerosis, and glaucoma It has a higher tar content than tobacco, so smoking cannabis presents the same health problems: bronchitis, emphysema and lung cancer Cannabis has an effect on the heart, similar to the effects of exercise. It may be just as good for the heart as going to the gym It can disrupt the control of blood pressure increasing the risk of fainting. Even occasional use is bad for people with heart and circulation disorders, and for those predisposed to schizophrenia

Origin of the species
The drug itself is derived from Cannabis sativa or Cannabis indica, a plant related to nettles and hops that grows wild in many parts of the world. Cultivation dates back thousands of years.
The first written account of cannabis use can be found in Chinese records dating from 2800 BC. However, experts widely accept that cannabis was being used for medical, recreational and religious purposes for thousands of years before that.

Cannabis plant The plant is believed to have originated in the mountainous regions of India.

When left growing wild, it can reach a height of 5 metres and flowers naturally from late summer to mid autumn.
Customs estimate that up to 80% of cannabis resin entering the UK originates from Morocco and most smuggled supplies in its herbal form come from Jamaica. However, an enormous amount of cannabis these days is actually home-grown.
Read about the different forms of cannabis and the effects it has on the body.