Even brief and secondhand exposure to tobacco smoke damages cells and inflames tissue straight away, and repeated exposure weakens the human body’s ability to repair the damage, a new report from the US Surgeon General reveals.

The scientific report, titled “How Tobacco Smoke Causes Disease: The Biology and Behavioral Basis for Smoking-Attributable Disease” and released earlier today, is Regina M. Benjamin’s first report as US Surgeon General and the 30th smoking-related report from that office since 1964.

In a statement timed to coincide with the release of the report, Benjamin told the media that:

“The chemicals in tobacco smoke reach your lungs quickly every time you inhale causing damage immediately.”

“Inhaling even the smallest amount of tobacco smoke can also damage your DNA, which can lead to cancer,” she stressed.

The comprehensive report itemizes a number of pathways through which the chemicals in tobacco smoke damage the human body and lead to disease and death, said the US Department of Health and Human Services (HHS).

The report also explains why so many people struggle to quit smoking. It says research shows that cigarettes are designed to be addictive and today’s products are designed to be more attractive and addictive than ever before, delivering nicotine faster and more efficiently than previously.

There are more than 7,000 chemicals in tobacco smoke, which the HHS describes as a “deadly” mixture containing hundreds of toxic substances, and at least 70 known to cause cancer.

One in three deaths to cancer in the US are tobacco-related.

More than 85 per cent of lung cancers are smoking-related, and smoking can also cause cancers that affect most other parts of the body.

The report also describes how:

  • Every time a person is exposed to tobacco smoke, they are exposed to substances that can damage DNA in a way that results in cancer.
  • Exposure to tobacco smoke affects the body’s ability to respond effectively to chemotherapy and other cancer treatments.
  • As soon as people are exposed to the chemical mixture in cigarette smoke, the delicate lining of their lungs is already reacting and becoming inflamed.
  • Repeated exposure over time can lead to more serious lung diseases such as chronic obstructive pulmonary disease (COPD) including emphysema and chronic bronchitis.
  • Our blood responds to chemicals in tobacco smoke, and these quickly damage blood vessels and make blood more likely to clot.
  • Smoking causes cardiovascular disease and increases risks for heart attack, stroke, and aortic aneurysm.
  • Even brief exposure to second hand smoke can result in cardiovascular disease, heart attack and other acute cardiac events.
  • Smoking makes it harder for diabetics to control their blood sugar and for women to get pregnant; it causes miscarriages, preterm births, low birthweight; and damages fetal lungs and brain tissue.
  • Infants exposed to secondand smoke are more likely to die from sudden infant death syndrome (SIDS).

Benjamin urged that it is “never too late to quit, but the sooner you do it, the better”.

“This report makes it clear quitting – at any time – gives your body a chance to heal the damage caused by smoking”, she added.

HHS secretary Kathleen Sebelius said over the last two years the US government has increased efforts to reduce tobacco use, including bringing in new legislation, investing in local tobacco control measures, and widening insurance access so it covers tobacco cessation.

“This will remain a key priority of this Administration,” she added.

— Download full report, executive summary and easy to read guide.

Additional source: US Dept of Health and Human Services (press release 9 Dec 09).

Written by: Catharine Paddock, PhD