At first the entire group – Viagra – and placebo-takers – suffered from altitude sickness. Blood pressure, which is a fairly good measure of how well you are acclimatising, rose 29 per cent. But by the sixth day, something interesting happened. While the placebo group’s blood pressure remained 21 per cent higher than normal, the Viagra group’s blood pressure was 6 per cent lower than during earlier low-altitude testing. Although both groups got breathless during exercise, the Viagra group had faster recovery rates during exercise than the placebo group.
Ancient and modern medicine has failed to really get to grips with altitude sickness. The German health service refuses to prescribe Diamox – a sulfa drug that most high-altitude climbers use. Dr Peter Hackett of the Institute for Altitude Medicine disagrees with the Germans. The source of this lack of a unified approach lies in the holistic nature of the illness; every part of the body suffers when oxygen levels drop, so specialists in one area can be at a loss because they cannot grasp the whole picture. My own experience taught me how nuanced control of the ailment is: small adjustments made at the right time seemed to have a big effect.
Those who are ‘adapted to altitude’ could be marginally superior in lots of areas – all of it adding up to greater efficiency overall. They could be efficient at removing water from the interstitial lung area, thus improving oxygen uptake. They could be better adapted to wet breathing, not using so much energy to warm and moisten incoming air (which takes up a lot of energy). They could be less sensitive to cold – which also takes a lot of oxygen. They could be supremely fit, so that excess work at altitude does not take such a toll – though this is by no means as crucial as it sounds; plenty of supremely fit people are bad at altitude. They are likely to be ‘good breathers’, meaning that in any single breath they manage to maximise the extraction of oxygen, which results in dilated rather than constricted blood and air vessels. This hinges on being relaxed as much as adequate CO2 levels. We will later hear of Tibetan monks who can increase their skin temperature by up to 6 degrees, and plenty of biofeedback dabblers can raise hand temperature and heart rate at will. There is no question that we can interfere with autonomous bodily functions in a negative way through fear and anxiety; could we not also benefit from imposing relaxation and calm?
On each occasion that I went to altitude, my experience was different. This is far from uncommon – most of the accounts of Himalayan climbers relate occasions when they had a bad time at altitude and on other climbs were in ‘perfect condition’. Certainly, Harold ‘Bill’ Tilman suffered at altitude at first (despite farming land in Kenya at 2,000 metres for over ten years) but later became very well adapted. I wonder if there is a parallel with diving, where beginners panic and gulp air; this results in too much of a reduction in CO , which leads to vasoconstriction – similar to an asthma attack – which then requires a further panicky deep breath. The cycle is broken by gradual relaxation. Divers become more efficient at breathing without really trying; they simply know they want their air to last longer. Similarly, climbers become better and more efficient at breathing at altitude – they learn not to indulge in activity that leaves them breathless because this will set off the vasoconstriction cycle.
I found that any excess exercise at altitudes above 3,000 metres was punished – unless I was already acclimatised. In my experience, the best way to acclimatise is not to exercise at all, just focus on very gently moving higher up the mountain each day. If you can sleep at only 300-metre increments each day and never get out of breath while doing it, I think the process will be as efficient as any other. Often I went over 1,000 metres in a day. What I noticed was that I would feel fine until lunchtime, but after a heavy lunch cooked by a willing Nepali, I would find the afternoon a struggle. We forget just how much energy is used in digesting food. Protein takes the most energy, then roughage, followed by fat and carbohydrates. It is interesting that the people most adapted to altitude living – Tibetans – put butter and salt in everything they can. They also tend to eat porridges and teas, which are much easier to digest than solid food. Salt is vital for remaining hydrated and melted butter is a good way to take on fats, which require less energy to digest than other foods easily available.
Those people who live year round above 4,000 metres – Tibetans and Andeans – have over time evolved to deal with altitude. Though they are not immune to altitude sickness, they are very much happier high up and crucially can do more work than an acclimatised non-native can.
Tibetans have been living on the Tibetan Plateau, which varies between 3,500 and 5,000 metres, for over 30,000 years. Andean tribes are considered to have been altitude dwellers for perhaps 11,000 years. These two groups have taken different evolutionary paths. Andeans have bigger lungs, more haemoglobin and more erythropoietin than sea-level dwellers. This means more air is processed to extract more oxygen. Tibetans don’t have big lungs or more haemoglobin – actually, they have a little less than people living at sea level. What they do have is more nitric oxide. They breathe faster than others at altitude, but this doesn’t result in vasoconstriction because of the high nitric oxide levels in their blood (up to 200 times higher than in the general population). Nitric oxide is a vasodilator, used as a supplement by body builders through the precursor argenine found in such foods as spinach, sesame seeds, crab and shrimp. But Tibetans have it naturally. One can read accounts online of people using nitric oxide supplements to ease altitude sickness – anecdotally, it seems to work.
The evolution of these traits probably involves a well-known aspect of living at altitude: fertility rates are lower and people don’t have so many children. Those with a slight advantage – and Tibetans have two genes associated with lower haemoglobin – will tend to proliferate. Over time. It took fifty years after Spaniards moved to the Andes for the first child of Spanish-born parents to be conceived and survive childbirth. Even among natives of Tibet, fertility is lower than elsewhere. There is a reason why high mountain areas aren’t overpopulated. This may explain the prevalence of polyandry in Tibet and other enclaves at altitude – it improves the chances of conceiving if a woman has three husbands instead of one. In a highly fertile population, a woman with many husbands would be exhausted by childbirth; in the mountains, she may need several lovers just to get pregnant.
So not only does going higher expose us to dangers, it also reduces the number of offspring we can produce – strong Darwinian reasons to stay in the valleys. And, mostly, we have.
Why does one feel nausea at altitude? Before eating, it is due to changing pressure in the digestive system and the many imbalances caused by a change in oxygen at the cellular level. After and during eating, nausea can result because one doesn’t have enough oxygen available to digest the food properly – the body is shutting down superfluous activities to send oxygen to where it is most needed: the brain. This is one reason to eat only the food you want to at altitude. Steer clear of stodgy unpalatable food, thick candy bars, ‘trail mix’; go for easy-to-digest soups and drinks. The item that runs out quickest on a trek is usually hot chocolate. Followed closely by cigarettes.
One of the curious things about altitude is the prevalence of high-altitude smokers. Stephen Venables, arguably one of the greatest high-altitude climbers ever, was still smoking the odd roll-up cigarette when he climbed Everest without oxygen. The great pre-war climbers were often photographed at base camp holding a pipe. Excessive smoking is obviously counterproductive, but smokers have higher CO2 levels – which means less vasoconstriction and more efficient oxygen uptake. A smoker who stops smoking within a few days of starting a climb will also tend to have more haemoglobin, thus smoothing the transition to altitude. Smokers’ bodies are also accustomed to running on lower amounts of oxygen – even at the cellular level – which makes getting all the body’s systems into alignment easier than for someone whose body has never experienced a sustained drop in oxygen levels.
There are a number of unexplored avenues in altitude studies. One is the i
ntriguing possibility that the way you breathe has a big effect on how you acclimatise and how you deal with altitude. The body is relatively good at dealing with low oxygen levels, once all its systems are in alignment; what it is bad at is handling high levels of CO2 – and overreacting to low levels of CO2. A number of breathing methods, pioneered with asthma sufferers, seek to increase CO2 levels so that an overreaction leading to further hypoxia is avoided. Asthmatics are taught to breathe through the nose, hold the breath to the count of five or ten, then breathe in again. This helps reduce ‘overbreathing’, a problem whereby the asthma sufferer sucks in a lot of air through their mouth, which scrubs out all their CO2, leading to vasoconstriction and poor oxygen intake.
Another unexplored link would be the use of certain supplements which we know work against hypoxia at sea level. These include Coenzyme Q10, typically given to heart-attack patients suffering mild hypoxia, and nitric oxide, which, as we have seen, allows Tibetans to breathe more deeply with vasoconstriction. In a way, the altitude drug Diamox, which alters blood acidity thus signalling that there is more CO2 in the blood than there really is, fools the brain, which equates acidity with C02 presence; this triggers deeper breathing and more oxygen. Essentially, it performs the same function as nitric oxide – though Diamox is much more powerful.
In my subsequent visits to altitude I was much more gentle in the way I approached higher and higher levels. I spent days running around at 1,800 metres in Darjeeling – lower than the level at which altitude problems start, but still a place where the amount of oxygen available to breathe (due to lower air pressure) is 20 per cent lower than sea level. If you can exercise without generating an excessively low CO2 response with all the bad effects of vasoconstriction, then running at lower altitudes is a very effective way to build up some immunity to mild AMS. The runners Adrian and Richard Crane, who famously ran the Himalayas at altitudes ranging from 2 to 5,000 metres, were very rarely incapacitated despite running each day.
But once I got above 2,500 metres I took it very easy, trying to establish rhythms of exercise rather than sudden bursts. Keeping going without getting out of breath is THE best way to avoid altitude problems, because you never engage in the overbreathing associated with low CO2 and vasoconstriction.
Nepalis and Tibetans emphasise eating vasodilators such as garlic, and salt is loaded into each meal – which helps water uptake. Wearing sunglasses helps too; there may be some obscure connection yet to be discovered between vasoconstriction and bright sun glare – I know that walking fully covered in the desert one can keep going far longer than if bright sunlight gets into your eyes. There is also anecdotal evidence that hay fever sufferers benefit from wearing dark glasses. We’ll see later that early Himalayan climbers thought that sun blindness contributed to mountain sickness. Perhaps it brings on vasoconstriction, which in turn exacerbates features of Acute Mountain Sickness. Being well hydrated, wearing full-cover sunglasses, eating easy-to-digest food and never over-exerting oneself is a good start to acclimatising.
Shamans go higher: the less oxygen you have, the more you focus on what is right in front of your nose. Mindfulness becomes obligatory. ‘Higher’ thoughts occur naturally. As you struggle to breathe, you think about your life, where it is going.
I am at 16,000 feet when I cross a huge dried-up lake. Frosted over, it looks like a snowy desert. The path I am on is cut into the rocky cliffside. It is steep and every forty paces I stop to rest. Then I go on too fast and have to rest again, after thirty paces, then twenty paces. I am still not practising the lesson of Bert’s researches: work is penalised exponentially at altitude. For every step you go faster than you should, you are docked two steps’ worth of oxygen. But within me surges something more than mere pain, more than simply wanting to show I can make it to the ‘top’. I sense the benefit of the focus I am achieving. And it is all down to the fact that I am, at last, listening to my breathing.
Instead of thinking about where the others are, looking at my watch, counting my paces, I am simply listening to my breathing. I slow my pace to a point where my breathing can keep up. Some sort of inner regulator kicks in. I know instinctively what speed I can walk at and seemingly keep it up for ever. Every time I scramble over a rock, I slow right down. You can only maintain this level of activity by moving very slowly.
Listening to my breathing, I am reminded of the great noise the air makes going in and out when one is diving with a regulator and compressed air bottle. Acting coaches claim that the single key way to improve performance when on stage or interacting with others is to be aware of your breathing. It is the mainstay of many spiritual exercises. Listening to your breathing is not just good for presenting, it’s good for being present. Your ‘centre’ goes from being up in the abstract world of your head to firmly within your body. You shift to living in the now.
As you get higher, your senses make less sense, and you pay less attention to them. Sight becomes less crucial as you fix your eyes on the ground a mere three feet ahead. That’s partly for safety – to see where you should tread – and partly because it is too painful to see how far you have to go. But you listen to your breathing. Maybe you are getting into alignment with something beyond the petty confines of the body. I remember when I wanted to help my children sleep when they were tiny I used to synchronise my breathing with theirs and very quickly they would drop off. So would I, if I wasn’t careful.
Near the summit, I do not rest. Instead, I ditch all my gear – heavy camera, coat, water bottle – and head off, unencumbered, up the rocky slope. I am rewarded handsomely for shedding weight. I am moving more easily despite the fact the slope has grown steeper. There is snow here and I inwardly rejoice. I am at last truly in the mountains. As a child, I loved snow and looked forward to playing in the stuff, no matter how thin the layer. But this snow is deep; sometimes I sink in up to my knees. Then it is past and I am back on the rocky path. This time I vow to never stop. If this means slowing to a virtual halt and walking like a slow-motion puppet, I’ll do that rather than race ahead and rest. The strategy works. The others up ahead are resting. I catch them up just before the final push to the pass. I can feel the burn in my legs but my breathing is fine. I can keep going like this for as long as I have to.
At the top, prayer flags flap. Printed on cheap polyester, the flags adorn every pass and summit in the Himalayas like bunting. Higher peaks are seemingly very close. They look like starched white sheets folded into peaks. I bow to the mountain and follow the guide’s prayer. Now we are no longer moving, it’s easy to breathe. I give thanks to all the gods.
10
A Cure for Altitude Sickness That Will Cost You
An eagle with clipped wings is not a dove.
Afghan proverb
As we’ve seen, there are natural cures for altitude sickness that are practised by Himalayan local people. Eating garlic, drinking a lot and walking at a steady pace can help lowlanders acclimatise to the high passes. But there are also drugs – which conveniently only grow in the place where they are most needed. Ophiocordyceps sinensis, or caterpillar fungus, is prized as a cure for altitude problems as it functions like nitric oxide (and Viagra) to maintain blood-vessel diameter as one went higher. But that same functionality also makes Cordyceps a natural form of Viagra – and for that reason, it is highly sought after in China.
In fact, it is so sought after, some are willing to kill in order to get their hands on it. In 2009 some Nepalese Gurkhas, trying to prove themselves and make a bit of money, targeted the Cordyceps fields of their neighbours – the more passive Buddhist Narpa people. Hindu Gurkhas are known for their fighting prowess as mercenaries, but they also provided support for the Maoist insurgency that dominated the late 1990s and 2000s. The Narpa tended to favour the monarchy and the status quo, living as they did in an isolated spot that did not have a jail, so rare was crime in their area.
The Gurkha lads were not expert Cordyceps thieves. They were spotted loitering – all seven of them �
� by a herder from the village of Nar. There was already bad blood between the two tribes – several years earlier a Nar elder had been beaten to death and the Narpa believed Gurkhas were responsible. It was a case of finally having a real reason for bashing their neighbours. The herder rushed into the village and something very ancient and atavistic happened: every household had to give up one member – not only to defend their land and the valuable crop, but also to ensure that all would be implicated in the crime they knew they were about to commit. The conversations were all in the Ng language, the almost secret tongue of the Narpa, which no other Nepalis speak. The Narpa had much to defend – most houses now had a solar panel capable of running a hot plate and three lightbulbs, which meant a much lower requirement for firewood or yak dung. The village made upwards of $65,000 a year from the fungus; take that away and you have a huge hole in the local economy.
Ophiocordyceps sinensis is the most expensive herbal supplement in the world – or it was in 2008, when this wild fungus that grows in only one place in the world fetched the astronomical price of $75,000 a kilogram. In other parts of the Himalayas – rural Tibet – 40 per cent of all cash income is estimated to come from the fungus, something over $225 million. Between 85-185 tons a year are harvested, which, for a very lightweight piece of dry fungus, is an awful lot of picking. Indeed, in Tibet, the bribe of choice isn’t cash, it’s a piece of Cordyceps fungus (or preferably several pieces). You have to be careful buying the wild product though; local collectors traditionally used sticks to hold the fruit of the mushroom in bundles, but in recent years they’ve taken to using a piece of solder wire instead. This adds to the weight, but also imparts a lead toxicity to the product.
Nepalese, Bhutanese, Tibetans and Chinese all search for Cordyceps in the high places of the Himalayas – it grows best above 4,000 metres, wherever the ghost moth, of the Thitarodes genus, also lives. Excavation must be careful – the tool of choice is often a spoon. A harvest of twelve to fifteen pieces a day is not unusual. Yaks are watched – where they are unusually lively, eating caterpillar fungus is generally the cause.
White Mountain Page 7