Poltatko kannabista? Et todennäköisesti saa emfyseemaa, kertoo Harvardin tutkimus

Do you smoke cannabis? You're less likely to get emphysema, says Harvard study

Can smoking cannabis cause emphysema or lung damage in the same way that tobacco does? A new Harvard Medical School study offers a clear answer: it doesn't seem to.

The study, published in May 2025 in the journal Current Problems in Diagnostic Radiology , is based on chest CT scans of 285 people, including both tobacco and cannabis users, as well as non-smokers. The results are interesting – and even comforting for cannabis users.

Tobacco is harmful, cannabis is not – from the lungs' perspective

The three groups of the study:

  • 89 non-smokers

  • 97 cigarette smokers

  • 99 cannabis users only

The result? Cigarette smokers suffered significantly more often from emphysema and coronary artery calcification. Cannabis users did not experience similar pulmonary hyperplasia or heart damage. The researchers concluded:

“Cannabis users do not appear to develop emphysema or pulmonary hyperinflation.”


Smoke in the air, but not the same smoke

Although cannabis and tobacco can both produce smoke, they do not affect the body in the same way. Several studies have previously shown that cannabis smoke is not as harmful as tobacco smoke . Lung cancer, chronic obstructive pulmonary disease (COPD), or emphysema do not occur in cannabis users at the same rate as in smokers.

Why? Possible reasons include:

  • Cannabis is generally used less frequently than tobacco,

  • the plant does not contain additives such as tobacco products,

  • the mechanisms of action are different (e.g. cannabinoids vs. nicotine),

  • The forms of use are more diverse, e.g. vaporization.

Vaporization: Less Harm, More Control

Vaporizers were also highlighted in the study. These devices heat cannabis below its combustion point , allowing the active compounds in the plant to vaporize without smoke. This significantly reduces exposure to harmful combustion products and makes use much easier on the respiratory system.

Clinical studies have shown vaporization to be a safe and effective method of use. This is good news for home growers: you can use your own crop pure and vaporized without additives, making the experience not only pleasant, but also gentler on your lungs.

NORML: The science is clear, but the politics are dragging on

NORML Deputy Director Paul Armentano summarizes the situation this way:

“Tobacco kills hundreds of thousands every year, but it is not banned. In contrast, cannabis, which does not cause similar health problems, remains heavily regulated in the United States.”

Although the debate is taking place in the US, it is also relevant in Europe. In many countries – such as Germany and Switzerland – the status of cannabis is currently changing. In Finland, the debate is only just beginning, but an informed approach is the best basis for responsible decision-making.

What does this mean for the breeder?

Home growing offers the opportunity to produce your own, pure, additive-free cannabis of known quality. When growing conditions are controlled – for example in a well-designed cabinet – the end result is also safer and easier to use.

The study provides further evidence why responsible, independent parenting is a good option. When you know what you are raising, you also know what you are breathing.

Back to blog