Smoking Behavior Compensation for Normal Nicotine Doses
How do you determine how much nicotine you get from a cigarette?
The concentration of nicotine you receive in the smoke stream can be computed with the following formula:
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This formula computes the amount of nicotine per unit volume of smoke puffed. It seems that the only way for a smoker to get more nicotine from a cigarette is to take bigger or more frequent puffs.
While this may seem pretty boring, it is, in fact, very exciting. Why?
Why You Smoke
The tobacco companies know that you smoke for only one reason: to get a dose of nicotine. Therefore, tobacco companies have two objectives:
- Produce cigarettes that appear to be low in tar and nicotine
- Produce cigarettes that deliver the amount of nicotine the smoker requires
Tobacco companies engineer their cigarettes to achieve both objectives for most cigarette brands. They worked to accomplish this as the British American Tobacco Company memo indicated: "What would seem very much more sensible, is to produce a cigarette which can be machine smoked at a certain tar band, but which, in human hands, can exceed this tar banding . . ."
This has results in to concepts of low tar cigarettes:
- Health-image cigarettes that merely appear to be more healthful, and
- Health-oriented cigarettes that actually deliver reduced tar and nicotine
The following table shows how successful the tobacco companies have been in controlling the government smoking machine measurements of nicotine over time. As you can see, the tobacco companies have been very successful at reducing the nicotine measured by the smoking machines.
How can smoking machine measurements decrease while nicotine delivered to smokers remain fairly constant?
The main consideration is that government measurements of tar and nicotine are performed under strict conditions in a prescribed manner. And, the actual amount of tar and nicotine you get from smoking a cigarette is determined by how you, as a individual, actually smoke.
Cigarettes can deliver more tar and nicotine when used by a human smoker than when smoked by a machine. This is referred to as elasticity. An "elastic" cigarette, regardless of the stated tar and nicotine content, will provide whatever does of nicotine you want if you adjust how you smoke it.
What Determines the Amount of Tar and Nicotine a Cigarette Delivers?
The amount of tar and nicotine that is drawn from a cigarette depends on a number of factors. The most important factors are:
- Architecture of the cigarette paper
- Tobacco type
- Concentration of tobacco in the tobacco rod
- Filter architecture
- The number of puffs you take on a cigarette
- The average volume of each puff
- The time duration of each puff (or the strength of each puff)
The tobacco companies understand how to use these factors to give both the government smoking machines as well as the smokers exactly what they want.
How Advertised Tar and Nicotine is Measured
In the United States, the tar and nicotine content cigarette manufactures are allowed to advertise is determine in a precise, predefined manner.
A standardized smoking machine is used to simulate the manner of smoking by an "average" smoker.
Government Cigarette Smoking Machine Standards
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The tobacco companies have engineered cigarettes to produce desirable tar and nicotine measurements for the government smoking machines. They have spent years and millions of dollars researching exactly how to construct cigarettes for the smoking machine tests.
The following are the main ways cigarette manufactures manipulate the smoking machines. These techniques fall into two categories: (1) Reducing the number of "puffs" and (2) Reducing the concentration of tar and nicotine in the smoke stream.
Main Ways to Reduce Standard Tar and Nicotine Yields
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What Amount of Tar and Nicotine Do You Actually get?
While the machine measured tar and nicotine yields for cigarettes has declined by over 60%, there has not been any significant decline in cancer risk for smokers using low yield cigarettes. While lung cancer rates among women continue to increase, lung cancer among men has declined nearly in proportion to the decline in men smokers.
All this serves to indicate that smokers continue to get much the same amount of tar and nicotine as they did with higher tar and nicotine cigarettes.
Since the primary purpose of smoking cigarettes is to get the required does of nicotine, smokers have compensated for the changes in cigarette design. That is, they smoke these low tar and nicotine cigarettes in ways that deliver the required nicotine does. Here are the main ways smokers have compensated:
Puff Frequency
The government smoking machines puff once per minute. While on average, humans take a puff every 34 seconds. Studies cited by the Surgeon General indicate average puff rates between once ever 18 seconds to once every 64 seconds. These numbers are average puff rates for all the participants in the particular studies cited. The actual puff rates for individuals vary more widely.
The important item to note is that people generally puff more frequently (every 34 seconds) than the government smoking machines (one puff per minute). This means that, given no other variations, human smokers generally take in about 76% more tar and nicotine than that indicated on the cigarette pack.
Puff Volume
The amount of tar and nicotine you receive depends on the amount of smoke you take into your lungs. This depends on volume of smoke you draw from the cigarette with each puff.
The puff volume taken in by the government smoking machine is 35 ml. Studies summarized by the Surgeon General report an average human puff volume of 43 ml. The average puff volumes of each study range from 22 ml to 66 ml. And the puff volumes of individuals in the various studies had wider ranges.
What this means is that the average smoker puts nearly 23% more smoke in their lungs than do the government smoking machines. This provides more tar and nicotine than is indicated on the cigarette pack.
Filter Vents
Filter vents are small holes in the filter. These holes are normally created by electrostatic sparks, by laser, or mechanically. The holes are small and normally positioned within 11 to 15 mm (about half an inch) of the filter opening.
These filter holes allow air to enter the filter to mix with the smoke stream. This air dilutes the smoke stream and reduces the concentration of tar and nicotine. Depending on the number of vents and their size, current filter vents dilute the smoke stream up to 83%.
Here is data from one study indicating how different numbers of filter vents reduce the nicotine measured by the government smoking machines.
Compensating for Filter Vents
There are several ways to obtain the expected nicotine dose from cigarettes with filter vents. One way is to take a bigger puff.
Taking a bigger puff (increasing puff volume) is an attempt to take in the required amount of nicotine despite its being diluted by vent holes. It seems obvious that if the smoke stream is diluted to 50% (equal parts smoke and air) then by taking in twice as much (100% more) diluted smoke, you will get the same amount of tar and nicotine you would get with a normal puff without dilution.
The actual formula for determining the increase in puff volume required is as follows:
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So, you can overcome the dilution of the filter vents by taking a larger puff. You could draw enough more smoke into your lungs to provide the expected amount of nicotine you would get with a normal puff with no filter vents.
For example, a Marlboro Full Flavor cigarette has filter vents that dilute the smoke by 13%. You can overcome this dilution by taking a puff that is just 15% larger than your normal puff.
A second way of overcoming the filter vents is to block them. Many smokers do not realize their brand of cigarettes has filter vents. Yet, they subconsciously have learned to cover the vent holes by covering the holes with the lips (by placing the cigarette further in their mouth). Another way to cover some of the holes is to place your fingers over the holes as you puff on the cigarette.
Research has found that smokers will frequently insert low tar and nicotine cigarettes further in their mouth as they smoke.
A third method to overcome the filter vents is to draw harder on the cigarette. The vent holes are not as effective in diluting the smoke stream at higher flow rates. Thus, by drawing harder you get a higher concentration of nicotine and tar.
The fact that concentrations of tar and nicotine is higher when the smoke stream in drawn faster is widely known in the tobacco industry.
Brown and Williamison uses a formula to describe "brand elasticity". This formula describes how nicotine concentration varies with different puff volumes. In each case, the puff volume is drawn in 2 seconds. The differences in volume represent the different in smoke flow rate through the cigarette.
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If the nicotine concentration is greater at the 56 ml puff volume that at the 44 ml puff volume, then the elasticity is greater than one. In such as case, smokers can receiver greater concentrations of nicotine with stronger puffs.
This has been known to the tobacco industry for some time. They have engineered cigarettes to deliver higher yields of nicotine than smoking machines measure. Here is a conclusion from the U.S. Department of Health and Human Services' Monograph 13:
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These internal tobacco company documents suggest that the effort to
develop low-yield cigarettes was conducted with a clear appreciation of the
compensation to preserve nicotine intake that was likely to occur in smokers.
Cigarettes were designed with elasticity of delivery in an effort to provide
low machine yields, allowing marketing of the product as a “health-reassurance”
cigarette while continuing to deliver high levels of nicotine to
satisfy the addictive demands of the smokers of these cigarettes.
Monograph 13, Risks Associated with Smoking Cigarettes with Low Machine-Measured Yields of Tar and Nicotine, p. 71 |
A fourth way to increase nicotine is to take more frequent puffs. Doing so increases the total number of puffs for each cigarette, thus increasing the nicotine intake.
And, a fifth way to maintain your nicotine dose is to smoke more low tar and nicotine cigarettes. A smoker who smokes 10 regular cigarettes may switch to a low tar cigarette. But, if he or she now smokes 15 low tar cigarettes to get the same nicotine does per day, he or she will see no reduction in tar and nicotine intake.
Conclusion
Switching to low tar and nicotine cigarettes may or may not reduce your tar and nicotine input.
If you switch to a low tar and nicotine cigarette, but compensate to get the same dose of nicotine as you did before, your tar and nicotine intake will not be reduced.
If you switch to low tar and nicotine cigarettes as part of an overall program to reduce your nicotine intake, compensate minimally, your intake of tar and nicotine will be reduced.
Resources
Monograph 13, Risks Associated with Smoking Cigarettes with Low Machine-Measured Yields of Tar and Nicotine
