Stimulation of cold receptors in the airway is thought be the mechanism of action for these perceived sensations of nasal decongestion and respiratory ease [ 18 ].
In vivo experiments indicate that inhalation of menthol can inhibit ventilation in guinea pigs [ 19 ] and in newborn dogs [ 20 ]. In humans, ingestion of a menthol lozenge significantly increased time between breath intake and exhalation or breath hold time [ 21 ]. In addition, menthol reduced bronchoconstriction in guinea pigs by relaxing preconstricted bronchi in vitro [ 22 ] and inhibited airway smooth muscle contraction in vivo [ 23 ]. By inhibiting respiratory rates and increasing the perception of airflow, it has been postulated that menthol may alter inhalation patterns during smoking [ 10 ].
Menthol has also been shown to be an effective antitussive cough-suppressant in animals [ 24 ] and humans [ 17 ]. At low concentrations, the inhalation of menthol facilitates expectoration [ 4 ]. Menthol gives plants of the Mentha species their typical minty aroma and flavor [ 8 ]. In addition to the mint flavor, menthol can produce a bitter taste when applied to certain areas of the tongue, similar to capsaicin [ 25 ].
Menthol-flavored chewing gum elicited higher amounts of saliva compared with nicotine-containing gum and placebo gum in a study of 25 nonsmokers [ 26 ]. In summary, the sensory and physiologic impacts of menthol as it is inhaled are complex. As menthol and nicotine are inhaled together, both will activate sensory nerve endings in the oral, nasal, and pulmonary mucosae [ 3 ]. Menthol stimulates thermoreceptors and nociceptors, as well as olfactory, taste and trigeminal sensory receptors [ 8 ].
The varying effects of menthol—cooling and warming, irritating and analgesic, depressed ventilation and ease of inhalation—depend on concentration and formulation, duration of exposure, and temporal factors.
Taste and flavor are also given as reasons for smoking menthol cigarettes [ 2 , 28 ]. Levin et al [ 29 ] analyzed how chemosensory flavor cues affect preference in a group of menthol and non-menthol smokers. Five different types of flavors were added to a cigarette substitute, two menthol-like and three tobacco-like. The addition of flavors, especially mint, increased the acceptability of cigarette substitutes.
In addition, both types of smokers liked the menthol flavors more than the placebo. The authors hypothesized that flavor and cooling sensations may provide a substitute for the tracheal stimulation involved in cigarette satisfaction [ 29 ].
Publicly available internal tobacco industry documents indicate the anesthetic properties of menthol are used to reduce pain sensations, mask the irritation of smoke, and enable initiation and increase uptake [ 10 ]. According to a review of publicly available tobacco industry documents, research associated with the tobacco industry found that menthol or mint-like flavor appears to be a main contributor to why some smokers choose menthol cigarettes [ 30 ].
Focus groups conducted by the tobacco industry found that non-menthol and menthol smokers define smoothness differently; non-menthol smokers look for absence of throat impact and tobacco taste, whereas menthol smokers define smoothness by absence of throat irritation and bitter flavor [ 30 ]. A total of eight studies contained information on smoking topography, including research on puff volume, puffs per cigarette, and other topography measures.
Seven studies have quantitatively investigated differences in puff volume with relation to cigarettes type or menthol smoker status. Two studies failed to find any association between menthol cigarettes and puff volume, and one found that menthol cigarettes was associated with an increased puff volume. Smoking topography studies comparing puff volume among menthol and non-menthol cigarette smokers. Both of these studies allowed women to smoke their usual brand of cigarette ad lib while a flowmeter cigarette holder attached to a differential pressure transducer measured puffing topography.
In the first study with 37 participants, women were equally stratified by ethnicity and menthol-smoking status. The second study of 95 women using the same parameters allowed to smoke brand of preference ad lib; equally stratified by race and menthol status found that menthol smokers had significantly larger puff volumes compared with non-menthol smokers Because these two studies allowed women to smoke their usual brand of cigarette, it is unclear how nicotine and tar yields may have affected topography measurements between the menthol and non-menthol groups since these yields were not controlled for.
Three small, experimental cross-sectional studies involved male participants only. Jarvik et al [ 33 ] recruited 10 Black and 10 White men from the Veterans Administration Medical Center; half of the participants in each group smoked primarily menthol cigarettes.
Study participants had two sessions, one week apart. In the first session, they smoked a commercially available non-menthol cigarette; in the second, they smoked a commercially available menthol cigarette. The test cigarettes had equivalent nicotine, tar, and carbon monoxide levels. Subjects smoked cigarettes as they normally would while topography measurements were taken on a smoking apparatus fitted with a Fleisch pneumotachygraph.
Thus, these differences appear to be due to smoker, rather than cigarette, characteristics. A similar study recruited 29 men 11 menthol smokers and 18 non-menthol smokers from an inpatient drug and alcohol treatment center [ 34 ].
In this within-subjects study, the subjects had two smoking sessions, one week apart, and were randomly assigned to smoke either the menthol or non-menthol cigarette first. The test cigarettes were commercially available brands chosen for their similar yields of tar, nicotine and carbon monoxide. Participants smoked the cigarettes under a rapid-smoking procedure, taking puffs every 15 seconds.
The smoker could determine the size of the puff, but maximum volume was cc only one subject consistently reached this point. Topography measurements were taken in a similar apparatus to Jarvik et al [ 33 ]. The mean puff volumes were lower when participants smoked menthol cigarettes than when they smoked non-menthol cigarettes Because of the unusual smoking regimen puff every 15 seconds , and because the study population was drawn from a treatment center, it may be difficult to generalize these findings.
A study by Miller et al [ 35 ] used a similar protocol, but with investigator-applied menthol one of three doses to the test cigarettes. Subjects were recruited from an in-patient substance abuse ward. Twelve Black men six menthol smokers and six non-menthol smokers were recruited.
Subjects took part in three trials, 1 week apart, with each trial testing a different level of menthol. Using a smoking apparatus, subjects took puffs every 30 seconds puff volume was set at a maximum of cc. All the smokers took in a cumulative 1, cc of smoke before they stopped. The order in which the 12 subjects smoked the menthol levels was counterbalanced by menthol dose to control for order effects. A racially diverse pool of male and female smokers participated in a smoking topography study by Strasser and colleagues [ 36 ].
Smoking topography data were collected while subjects smoked their usual brand of cigarette. Menthol smokers were not significantly different from non-menthol smokers when comparing total puff volume or mean puff volume [ 36 ]. Finally, Nil and Battig [ 37 ] recruited fifteen smokers 11 women and four men from a Swiss population. During six different sessions, the subjects smoked six different cigarettes: high 0.
Puff volume and puff interval were measured under natural smoking conditions and also under forced conditions, in which participants took 30 puffs with a new half-length cigarette presented after every third puff. Usual brand cigarettes were smoked in the last session as a reference.
Under natural conditions, puff volume per cigarette was higher in low-yield cigarettes compared with high-yield cigarettes, as is expected due to compensatory smoking.
Puff volume was greater in both high- and low-yield blond tobacco compared with high-yield menthol tobacco. There were many methodological differences that may impact generalizability of these findings, including small study sizes, use of only men or only women in a study, differences in study design with regard to smoking as usual ad libitum smoking vs. These methodological differences make it difficult to make comparisons and draw firm conclusions.
Seven studies measured the effect of mentholation on number of puffs per cigarette puff frequency and the data for number of puffs per menthol cigarette vs.
Published research studies comparing number of puffs per cigarette among menthol and non-menthol cigarette smokers. However, a study of 37 women that compared type of smoker menthol versus non-menthol found no difference between their number of puffs per cigarette [ 31 ]. Similarly, the dose-controlled trial by Miller et al [ 35 ] found that the number of puffs did not differ between menthol and non-menthol smokers and menthol dosage did not influence number of puffs for either type of smoker [ 35 ].
Strasser et al [ 36 ] also failed to find any menthol versus non-menthol differences in number of puffs when menthol smokers were compared with non-menthol smokers. A seventh study by Caskey and colleagues [ 38 ] recruited 28 men from an inpatient drug and alcohol treatment center, including in 12 menthol smokers nine Black, three White and 16 non-menthol cigarette smokers eight Black, eight White.
Subjects participated in two rapid-smoking trials, either with a non-menthol or menthol cigarette, one week apart. Smoke was manually withdrawn from the cigarette via a syringe, and the smoker inhaled 40 cc of this smoke every 15 seconds until he or she could no longer continue.
Although the researchers hypothesized that menthol cigarettes would allow smokers to take more puffs, no difference was found in the mean number of puffs between the two cigarette types; however, the authors concluded they did not have enough power to detect even a large effect size because of their small sample size.
In summary, three studies show menthol cigarette smokers taking significantly fewer puffs, while four studies showing no significant difference in number of puffs between menthol and non-menthol cigarettes. As with the studies of puff volume, there are several methodological weaknesses, including small study sizes, use of only men or only women in a study, differences in study design with regard to smoking as usual ad libitum vs. Methods used in published studies comparing topography measures amongst menthol and non-menthol cigarette smokers.
Three of the studies looked at topography parameters other than puff volume and puff frequency. Similarly, Ahijevych and Parsley [ 32 ] found no significant differences in mean puff duration, mean interpuff interval, or total puff duration between menthol and non-menthol smokers. Moolchan et al [ 38 ] looked at puff volume, puff velocity, puff duration, and CO boost increase in exhaled CO following smoke inhalation in a group of adolescent Black and White menthol smokers.
Topography measures and CO boost did not differ between the groups. Although topography is generally measured with quantitative measurements, three studies asked qualitative questions regarding menthol cigarette use. Menthol and non-menthol smokers reported similar puff frequencies, depths of inhalation, and length of cigarettes smoked [ 40 ]. A baseline questionnaire given to smokers in a cessation trial, however, found that menthol smokers believed menthol cigarettes to be more soothing to the throat than non-menthol cigarettes, and they felt they could inhale menthol cigarette smoke easier and deeper than smoke from non-menthol cigarettes [ 28 ].
In addition to measuring topography, Jarvik et al [ 33 ] found that subjective ratings of harshness did not differ between cigarette type menthol or on-menthol or between menthol and non-menthol smokers. This section focuses specifically on menthol, nicotine, and tar yields as they relate to smoking topography. Three studies have looked at the effect of menthol content or smoke yield on smoking topography or cigarette preference. The Ministry of Health in Chile , a country with high use of menthol cigarettes, particularly among women, tried to introduce a menthol ban under an existing law in Menthol cigarettes were initially exempted from a flavour ban in Canada in Evidence showed that menthol cigarettes were used by nearly a third of high school aged smokers.
Later the same year California passed a similar law, although some cigars and pipe tobacco were exempt. Moldova, an non-EU country in the lower middle income category with a high smoking rate, was also due to ban menthol cigarettes in May After protests against the TPD from the tobacco industry, and an ultimately unsuccessful legal challenge by Poland at the European Court of Justice , supported by Romania, implementation of the ban on menthol cigarettes was postponed to While the ban applied to cigarettes, some tobacco products were exempt: cigars, cigarillos and pipe tobacco.
Menthol accessories that were not sold within the same packaging as the tobacco or cigarettes were also excluded.
A leaked Philip Morris International PMI document from indicated that it opposed flavour bans and identified the European menthol ban as a threat to its business. See below for a description of the range of tactics used by tobacco companies to exploit loopholes in the legislation, and circumvent the EU menthol ban. An evaluation of a menthol cigarette ban in Ontario, Canada enacted in January found that having a ban in place was associated with a reduction in menthol and total cigarette sales, while this effect was not observed for a Canadian state without a ban.
Where neighbouring countries do not implement a ban, it has been suggested that there is a risk that smuggling will increase. However, the risk associated with the movement of illicit tobacco is often exaggerated by the tobacco industry.
Euromonitor International produces data on cigarette market share by volume of capsule cigarettes i. Note that Euromonitor receives project funding from Philip Morris International. However, regional distribution varies. According to market research data the figure was much higher in , nearly 1. When the revised TPD was approved, industry and retailers were given a 4-year delay to prepare for the menthol ban. Two exceptions were the UK and Poland, two markets with high proportions of menthol sales.
However, when approached by trade publication Better Retailing in April, less than a month before the ban, BAT refused to give further details. Infertility issues and weak immune systems are also more prevalent in smokers than non-smokers. Even in terms of mental health, while smoking is commonly known to relieve stress and help people relax, it has been shown to increase anxiety levels, and smokers are at an increased risk of clinical depression.
It is important to monitor your tobacco and nicotine intake and if you do find yourself getting addicted to tobacco products and want to quit, reach out to a healthcare professional or a support group to not only aid you in your journey of quitting, but also deal with withdrawal symptoms in a safe and healthy manner and reduce chances of relapse. So, sign in RN to get your daily dose of wellness.
Self Care. Smoking flavoured cigarettes, especially menthols, might give you that much-needed kick—but they can also do you more harm that regular smoking. Dr Tilak Suvarna 78 Likes. Login Sign Up.
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