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Russian Roulette with the Heart

The connection between smoking, drinking, and an unhealthy heart

A Tar-Covered Road to the Heart

Why do we spend thousands on something that makes us stink, forces us to stand shivering in pub doorways in the winter cold, and causes us to die an early and unpleasant death? Why do we smoke, when it puts our cardiovascular system under extreme stress?

It’s all the fault of dopamine, the pleasure and reward hormone in our brain. In our head, every cigarette is like a wonderful reward; it feels to a tobacco addict like a shot feels to a heroin junkie. This may be a simple answer, but it’s no help to someone trying to give up smoking. Thankfully, however, we have public health warnings such as: ‘Smoking causes ageing of the skin’. Boom! That really hits home! After reading that horrific warning for the first time, I felt awful, and my next cigarette was no pleasure at all. But was this any help to me? Of course not, because in such cases, addicts will simply increase the dose of the drug to force their brains to give them the reward that they crave, to make them feel better about the bad news.

I must admit that I set an extremely bad example myself when it comes to smoking. In anatomy lectures as a medical student, I saw smokers’ lungs that were as black as a tarmacked road, and, working as a paramedic, I met people whose smoking habit had left them confined to a wheelchair or bedridden with severe chronic lung disease. But all this was not enough to put me off enjoying the occasional cigarette in the pub — despite the fact that smoking really is one of the few habits that brings absolutely no benefits; although those of a rather cynical frame of mind have argued that smoking benefits the state pension system by causing smokers to die an early, if medically expensive, death. Smokers are playing a game of Russian roulette, only without passing the revolver on, since the lungs are far from being the only organs affected by the more than 4000 toxins contained in tobacco smoke.

What exactly happens when we smoke, and how can it be so damaging to our bodies? Cancer! That’s the first thought that springs to mind. Of all the substances we breathe in when we smoke, at least 40 are known to cause cancer. The biggest risk is that of developing the kind of tumour known in common parlance as lung cancer, which doctors refer to by the much more elegant-sounding term ‘bronchogenic carcinoma’. This happens when some cells in the bronchial tubes begin to mutate and, with time, are no longer able to perform their normal function. The affected cells then try to make up for that loss by constantly reproducing. They divide and multiply incessantly, creating a tumour that eventually impairs the functioning of the lung. If these cells then also find their way to other organs via the bloodstream — when we say the tumour has ‘spread’ — our entire body is affected, and death is the final result. If we know all this, how can we be so stupid as to keep on smoking?

Nicotine is the guilty culprit. In small doses, it causes a moderate release of adrenaline, the well-known stress hormone that stimulates us, suppresses hunger pangs, and increases alertness. What a wonderful natural drug! However, nicotine’s main effect is to cause the brain to release dopamine, the pleasure hormone we met above. Nicotine also causes both heart rate and blood pressure to rise.

When I was 18, I did an experiment on myself to observe the constrictive effect of cigarette smoke on our blood vessels. A friend of mine happened to own a thermal-imaging camera, so I used it to film my own hand while smoking. Before I lit up my cigarette, the surface temperature of my skin was 32 degrees Celsius. But even after only one puff, that temperature fell to 30°C. And after I had smoked the entire cigarette, the temperature of my hand was fluctuating around the 28–29°C mark.

So nicotine and tobacco smoke are addictive substances whose effects on our body are not only long-term; they have some pretty immediate impacts. Causing our blood vessels to constrict can be very serious: if a smoker already has a narrowing of one of the coronary arteries, a single cigarette may be the straw that breaks the camel’s back, causing the artery to close completely — and the smoker to keel over with a massive heart attack.

As well as nicotine, two other important substances contained in tobacco smoke are tar and carbon monoxide. The latter is a colourless, odourless gas that binds to the red blood cells, greatly reducing their ability to take up oxygen. They are able to do this because erythrocytes (you remember them, I’m sure — the RBCs) take up carbon monoxide much more easily than oxygen. In the most serious cases of carbon-monoxide poisoning, the gas displaces oxygen from the blood corpuscles to such an extent that the resulting lack of oxygen is life-threatening. This explains why many people who want to kill themselves choose to do so by deliberately inhaling the exhaust fumes of a running car engine, which contain carbon monoxide.

Smokers will notice dark-coloured mucous when they cough. The substance responsible for this discolouration is tar, which blankets the cilia in our lungs. Cilia are the little hair-like structures whose job is to wave constantly back and forth (looking for all the world like a field of corn in the wind) to transport mucous and any inhaled foreign particles, such as dust, out of the lungs and into the nose and throat area. The smoke from just one cigarette leaves the cilia paralysed for several minutes. So frequent smoking throughout the day means rather a lot of unwanted material collects in the lungs, making our breathing apparatus more susceptible to infection and other causes of illness.

Nicotine and tobacco smoke also reduce the concentration of ‘good’ HDL cholesterol in the blood, and increase that of ‘bad’ LDL cholesterol.^* Furthermore, they thicken the blood and damage the inner wall of the blood vessels. This is one of the main causes of arteriosclerosis,^† a real roundhouse punch with negative consequences for our cardiovascular system. It’s no wonder, then, that in Germany alone, 110–140,000 people die every year from the effects of smoking. In the US, the figure is 480,000; in Britain, it’s 100,000; while in Australia, it’s 15,000.

If, to make matters even worse, these effects are combined with other risk factors for heart attacks, such as high blood pressure, increased blood-cholesterol levels, and life as a couch potato who’s on first-name terms with every McDonald’s employee in town, the risk of cardiovascular disease can reach enormous proportions. In addition, smoking is one of the main causes of peripheral arterial occlusive disease (PAOD), known to most non-medics as smoker’s leg.

In this condition, the blood vessels of the legs become so damaged by deposits of fat and plaque that the patient has difficulty walking any distance. Sufferers have to take a break every few metres. Since this behaviour resembles that of a window-shopper, stopping regularly and often to admire window displays in town, it is sometimes known as ‘window-shopping disease’. A walk round the shops is supposed to be a pleasant experience, but in serious cases of PAOD, the undersupplied tissue can die off, and must be surgically removed.

Furthermore, tobacco smoke also affects our immune system, weakening it enormously. Men may smoke more and be more likely to suffer from vascular disease, statistically speaking, but that doesn’t mean that smoking isn’t also extremely dangerous for women. Especially women who take the birth-control pill. The contraceptive pill can increase the risk of the blood vessels becoming blocked by blood clots — a condition known as thrombosis. If a woman smokes while she’s on the pill, she is combining two risk factors and thus hugely increasing the likelihood of negative medical consequences.

All this means that, when it comes to smoking, there can be only one sensible decision: to kick the habit as quickly as possible. Even long-time smokers will really be doing their bodies a favour by quitting, since many studies show that an ex-smoker’s body will begin to regenerate soon after that last cigarette — slowly, admittedly, but continuously. Ah, that last cigarette; it really is the best one!

The first positive changes kick in just 20 minutes after the final puff. In that time, the ex-smoker’s blood pressure will have returned to the level it was at before that last cigarette. The body’s blood circulation and temperature begin to return to normal. After about half a day, the amount of carbon monoxide in the ex-smoker’s blood will have sunk to a safe level. This allows the blood corpuscles to deliver pure oxygen to our cells once again. After just one day, therefore, giving up smoking will already have helped the heart. And that considerably reduces the risk of a heart attack.

Two days after quitting, we begin to smell better, and I don’t just mean our body odour, but also, more importantly, our sense of smell. At the same time, our sense of taste begins to regenerate, which increases our quality of life immensely. The taste of ripe Italian tomatoes can now really blow your socks off!

After two weeks, our lungs begin to perform better, and even after just a month, the cilia will have regained their pre-smoking functionality. This means much less coughing to expel mucous and dust from our breathing apparatus. The result is that we suck more fresh air into our lungs with each breath we draw.

Once six months have passed since that final cigarette, the risk of suffering a heart attack will have sunk by half. And if an ex-smoker holds out for another six months — so, a whole year in total — then his or her risk of dying due to the effects of smoking will be about half as high as it was immediately after that last cigarette. Then the worst is over, although the danger of slipping back into old ways remains present for years.

I know this from personal experience. In my final years at high school and during my paramedic’s training, I no longer smoked. But when I went to Vienna to study, one single drag on a cigarette was all it took to put me back where I was at the time I stopped smoking. Unfortunately, we humans have an excellent memory when it comes to addictions. Even years after we quit, our body remembers how great the feeling was when we indulged our addiction. By contrast, the negative effects are soon forgotten. The simple fact is that our brains are greedy for dopamine.

Luckily, human beings also have the capacity to conquer their urges. For those who manage to quit permanently, their risk of suffering a heart attack will fall to the same level as a non-smoker within 15 years. It really is worth doing more than just thinking about quitting.

There’s also no reason to be afraid of withdrawal symptoms after quitting smoking. It is true: lack of concentration, increased irritability, and often bouts of sweating and nausea make life difficult at first; but, when you think about it, these are positive signs! They show that the body is adjusting to the new, altered circumstances it now finds itself in. So the best thing to do is simply grin and bear it, and to make sure you never have to go through it again!

Bomb Shots for the Heart