Vaping, smoking and even using nicotine gum and patches could increase the risk of deadly heat exhaustion, new research suggests.
The warning was issued as Britain braces for a “mini heatwave” this weekend, with the mercury expected to hit 31C in some areas. It also comes as new figures show one in ten adults are currently vaping.
An international team of researchers established a link between nicotine and heat exhaustion. To do so, they recruited 10 men who neither smoked nor vaped and gave them a nicotine patch to wear overnight.
The men were then asked to cycle non-stop for 60 minutes in rooms heated to 20°C and 30°C.
The volunteers’ temperatures were then taken, both internally, using a temperature-testing “pill” that is swallowed and then wirelessly transmits data to an app, and externally, on the skin.
The warning will be a particular concern for the one in ten adults who now vape, according to the latest figures published this week (file image)
Although it was initially promoted as a way to quit smoking, research shows that many of those who now vape have never smoked. Earlier this year, World Health Organisation (WHO) chiefs ruled that vaping cannot be recommended as a way to quit smoking as so little is known about the harms and benefits.
The forecast has prompted the UK’s Health Security Agency to issue a 54-hour heat health warning for large swathes of Britain.
The next day they were given a patch that did not contain nicotine and repeated the entire exercise.
This experiment was repeated four times and neither the participants nor the researchers knew when they received active or inactive patches.
Two participants had to withdraw from the 30°C nicotine trials because one had “reached the maximum ethical limit for gastrointestinal temperature” and the other dropped out due to “nausea and chills”.
Overall, the team concluded that nicotine use increases “thermal stress” during exertion, leading to heat exhaustion, by reducing blood flow to the skin.
Drawing on studies showing that ex-smokers tend to gain weight when they quit, physiologist Professor Toby Mundel of Brock University in Canada, who led the study, said: “Nicotine appears to speed up a person’s metabolic rate, basically increasing the number of calories they burn.”
Other studies also found that nicotine constricts blood vessels, so less blood flows to the skin.
Blood flow to the skin allows the body to release heat and provides the fluid for sweat. If this is restricted, the body can overheat, he added.
A yellow weather warning has been issued for 54 hours from 5pm on 18 July until 20 July, with the highest temperatures recorded in London, the south-east and east of England, and the East Midlands.
The warm weather comes after a wet start to July that saw the country inundated with 97 percent of the month’s usual average rainfall.
South-east England and London will be hardest hit by the heat, with temperatures likely to reach 31°C.
The weather is forecast to be milder on Sunday, but the Met Office warned of “minor impacts on the health and social care sector” that could “increase the risk of mortality among vulnerable people” before then.
Around one in five Britons is thought to smoke or vape, with rates of the latter habit rising dramatically, particularly among those under 25.
Although it was initially promoted as a way to quit smoking, research shows that many of those who now vape have never smoked.
Earlier this month, the heads of the World Health Organization (WHO) ruled that vaping cannot be recommended as a way to quit smoking as too little is known about the harms and benefits.
The world body’s decision contradicts NHS advice that the devices are an effective way to quit the habit, which is one of the biggest causes of illness and death in the UK.
In a world-first guide setting out possible interventions to help people stop using tobacco products, the WHO has described the evidence surrounding e-cigarettes as “complex”.
Vaping “may” be recommended as an aid to quit smoking “in the future as evidence accumulates,” he added.
Instead, health officials should support “behavioural” support, such as counselling or smartphone apps and nicotine replacement therapy, to help people quit smoking.
Professor Mundel said his team’s findings linking nicotine to heat exhaustion also raised concerns for the upcoming Olympics, which begin in Paris next week, because, paradoxically, many athletes smoke or vape.
Through urine tests collected during international sporting events between 2012 and 2020, Professor Mundel found that a staggering 55 percent of baseball players, 43 percent of hockey players and 42 percent of football players were nicotine users, based on elevated levels in their samples.
The last Summer Olympics in Tokyo, Japan, “were the hottest and most humid on record,” but the upcoming Games are predicted to potentially break those records once again.
“Holding the Olympic Games in an urban environment with limited green space and a lot of pavement and concrete – which absorbs heat – increases the risk of heat exhaustion for athletes and the viewing public,” he said.
Earlier this year, independent research revealed that one in five professional footballers, both male and female, use nicotine pouches containing snus, which they place in their mouth.
Professor Mundel said the results of his study are not only relevant to athletes, but also to other people working in high-temperature environments, including the military, firefighters and some industries.
Everything you need to know about electronic cigarettes
How much nicotine is in an e-cigarette?
There are many different brands of e-cigarettes, which contain different levels of nicotine.
The legal amount of nicotine in e-liquid in the UK is 20mg/ml, which equates to between 600 and 800 puffs.
The Elf Bar 600, one of Britain’s most popular vaporizers, is advertised with nicotine strengths of 0mg, 10mg, and 20mg.
How many cigarettes are in an electronic cigarette?
The Elf Bar 600 contains the equivalent of 48 cigarettes, analysts say.
It provides 600 puffs before you have to throw it away, meaning that, in theory, every 12.5 puffs is equivalent to one cigarette.
Experts say that for many e-cigarettes, 100 puffs is equivalent to ten regular cigarettes.
Elf Bars are a brand of e-cigarettes that are often sold in bright colors and with kid-friendly names and flavors, such as Blue Raspberry Lemonade and Green Gummy Bear.
Is vaping better for your health than cigarettes?
According to the NHS, vaping products are considered better than cigarettes as users are exposed to fewer toxins and at lower levels.
The health service adds that vaping instead of smoking cigarettes reduces exposure to toxins that can cause cancer, lung disease and heart and circulation diseases such as strokes and heart attacks.
Public Health England, now defunct, published an independent expert review in 2015 that concluded e-cigarettes are about 95 percent less harmful than traditional cigarettes.
However, vaping is not risk-free, as although levels in tobacco products are much higher, e-cigarettes still contain harmful toxins, according to a study by researchers at the Medical University of Silesia in Poland.
And Dr Onkar Mudhar, a London dentist who posts videos on TikTok, said Elf bars can cause inflammation, swelling and bleeding of the gums.
He said this is because nicotine dries out the mouth and reduces saliva, causing irritation due to the buildup of bacteria and food that cannot be washed away.
In 2022, there were nearly 350 hospitalisations in England for vaping, believed to be mainly due to respiratory problems such as shortness of breath, chest pain, lung inflammation and, in severe cases, respiratory failure.