Surviving Above the Clouds


SOLITUDE, majestic scenery, and opportunities to enjoy walking, climbing, and skiing attract many vacationers to the mountains. In addition, millions of people live permanently in valleys and on plateaus that are higher than many cloud formations. However, living so high up may have strange effects on people’s health or their motor vehicles and may also affect their cooking. What is the source of these problems, and how can they be dealt with? First, are there really so many people living high in the mountains?

Many highland areas have become economic growth zones. The teeming millions of Mexico City live at over 7,000 feet [2,000 m] above sea level. Denver, Colorado, U.S.A.; Nairobi, Kenya; and Johannesburg, South Africa are at elevations of more than 5,000 feet [1,500 m]. Millions of people in the Himalayas live at  over 9,000 feet [3,000 m]. In the Andes several large cities are over 11,000 feet [3,300 m] above sea level, and people work mines there that are 20,000 feet [6,000 m] up. With so many living in the highlands, the study of how the body adapts to life there has gained importance. What has been learned can deepen your appreciation for your body’s marvelous design.

What to Expect

The way Doug felt on arriving high in the Andes is typical. He says: “When handling our suitcases at the airport, I suddenly felt dizzy and nearly fainted. Although that soon passed, for the first week or two, I suffered from headaches and disturbed sleep. I would suddenly wake up with the feeling that I was suffocating. Then, for a couple of months, I had little appetite, tired easily, and needed more sleep.” Katty adds: “I used to think that all the talk about altitude problems was in people’s imagination. Now I know it isn’t.”

Doctors call the disturbed sleep that Doug experienced periodic breathing. It is common among people who have recently arrived at high altitude. But if it happens to you, you might call it scary. From time to time, while asleep, you may actually stop breathing for several seconds. At times, this might make you suddenly wake up, gasping for breath.

Some people have no problem at all after arriving in the altitude. A number of people experience unpleasant reactions at 6,000 feet [2,000 m], as do about half of newcomers at 10,000 feet [3,000 m]. Interestingly, high-altitude natives returning home after only a week or two in the lowlands often experience the same reactions. Why?

Why Altitude Affects Your Body

Most of the problems are caused by lack of oxygen. Because the atmospheric pressure is lower the higher you go, at 6,500 feet [2,000 m] above sea level, a given volume of air contains some 20 percent less oxygen, and at 13,000 feet [4,000 m], air contains 40 percent less oxygen. Lack of oxygen affects most of your bodily functions. Your muscles can do less work, your nervous system can take less stress, and your digestive system cannot handle fat as well. Normally when your body needs more oxygen, you automatically breathe more heavily and fill the need. Then why doesn’t this happen when you arrive at a high altitude?

Just how your body controls your rate of breathing is a wonder that is not completely understood. But when you exert yourself, heavy breathing is not triggered simply by lack of oxygen. Rather, the carbon dioxide buildup in the blood produced by the muscle activity seems to be a key factor in making you breathe more. You do breathe more heavily when at a higher altitude but not enough to compensate for the persistent oxygen shortage.

What causes the headaches? A speaker at the First World Congress of High Altitude Medicine and Physiology, held in La Paz, Bolivia, explained that many of the symptoms of mountain sickness result from an accumulation of fluid in the brain. In some people this causes pressure inside the head. Apparently, because of the size of their cranium, some people do not experience these effects. Nevertheless, in rare cases a life-threatening condition can develop. Loss of muscular control, blurred vision, hallucinations, and mental confusion are signs that warn you to seek medical help immediately and get down to a lower altitude.

Wise Precautions

The effects of high altitude reach their peak about the second or third day, so a few days before and after arrival, it is best to take only light meals, especially at night. After arrival, you should eat carbohydrates, such as rice, oats, and potatoes, rather than fatty foods. You may do well to pay attention to the advice, “Eat breakfast like a king, but eat supper like a beggar.” Also, avoid physical exertion, as it can bring on a bad attack of mountain sickness. Perhaps because young people  tend to disregard this advice, they are often the ones who suffer most.

“Slip on a hat, and slop on some sunblock cream” is good advice here too, since there is less atmosphere to protect you from the dangerous rays of the sun. Those rays can irritate or even damage your eyes, so use good sunglasses. The thin mountain air also dries up your tears, causing further eye irritation. The advice is to drink plenty of fluids.

Doctors have warned people who are seriously overweight or who have such conditions as high blood pressure, sickle-cell anemia, or heart or lung disease to have a careful medical evaluation before deciding on a trip above the clouds. * If you have a bad cold, bronchitis, or pneumonia, it may be wise to delay your trip, since high altitude together with a respiratory infection or heavy physical exercise can sometimes cause a dangerous buildup of fluid in the lungs. Respiratory complaints can cause even lifelong highlanders to become oxygen starved and experience serious health problems. On the other hand, asthmatics often feel better living higher up. In fact, a group of Russian doctors reported to the First World Congress of High Altitude Medicine and Physiology that they take patients with certain complaints to a high altitude clinic as therapy.

Settling in the Altitude

There is no need to fear living at high altitudes. In fact, some highland areas such as the Caucasus Mountains are famous for the number of natives who have lived unusually long lives. And some people have endured extremely high altitudes for years. An Awake! reader in the Andes relates: “I lived and worked for 13 years at a mine 6,000 meters [19,500 feet] high, near the top of a volcano. Breaking up blocks of sulfur with a sledgehammer was hard work. Yet, at day’s end, we used to play soccer!” The human body is endowed with such remarkable abilities to adapt to new conditions that we marvel at the Creator’s wisdom. How does your body cope with the lack of oxygen at high altitudes?

Your body’s first reaction on exposure to high altitude is to make your heart and lungs work faster. Then you shed plasma from your blood, thus concentrating the oxygen-carrying red cells. In a short time, extra blood is being diverted to your brain, where it is most needed. And within only a few hours, your bone marrow is already manufacturing  extra red blood cells, which may have an increased affinity for oxygen. All this means that although becoming fully accustomed to the high altitude can take months, within just a few days, your heartbeat and breathing can return to normal.

Problems With Motoring and Cooking

It isn’t just your body that is oxygen starved, however. Your motor vehicle will seem lethargic too. Even though your local mechanic may adjust the fuel mixture and advance the ignition timing for you, your engine will still have less power. But what is happening in the kitchen?

A fallen cake, crumbly bread, beans that never cook, and a runny boiled egg are just some of the problems that might make a cook weep. Why do these occur, and what can you do about it?

Culinary disasters are more frequent and noticeable when you are baking. The lower air pressure causes the gases that lighten breads and cakes to expand more than at sea level. The tiny bubbles in the dough or batter become large, making the product crumbly, or worse still, the bubbles may burst causing the cake to go flat. But the problem is not difficult to solve. If the cake is lightened with whipped eggs, simply do not beat them as much. Or if the recipe includes a leavening agent, use less. The New High Altitude Cookbook recommends 25 percent less leavening agent at 2,000 feet [600 m] extending up to 75 percent less at 8,000 feet [2,000 m].

When making yeast breads, watch that the dough doesn’t more than double in size. Since eggs strengthen the cell structure of cakes, when adapting your recipes, use extra-large eggs. Too much sugar, on the other hand, weakens the cell structure, so use a little less, since low air pressure also concentrates the sugar in your batter by evaporating the water more quickly. Actually, most recipes require more liquid because the thin, dry mountain air robs food of its moisture.

Nearly all food takes longer to cook at high altitudes. For example, a boiled egg needs a minute extra at 5,000 feet [1,500 m] and three minutes extra at 10,000 feet [3,000 m]. You will find a pressure cooker invaluable. In fact, at higher altitudes, you cannot cook beans and peas without one.

So do not be fearful of a trip to the highlands. You may have to huff and puff for a while, your sponge cake may look more like a pancake, and the car you are driving might respond like an arthritic tortoise, but if you are in reasonably good health, you will probably find the experience exhilarating.


^ par. 16 Some doctors prescribe acetazolamide to stimulate breathing at very high altitudes. Other drugs for mountain sickness are advertised, but not all doctors recommend them.

[Diagram/Pictures on page 12, 13]

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Some High-Altitude Cities and Mountains Around the World

—30,000 feet—​ [9,000 meters]

Mount Everest, Nepal and China

29,035 feet [8,850 m]

—25,000 feet—​ [7,500 meters]

—20,000 feet—​ [6,000 meters]

Mount Kilimanjaro, Tanzania

19,341 feet [5,895 m]

Aucanquilcha, Chile

17,539 feet [5,346 m]

Mont Blanc, France

15,771 feet [4,807 m]

—15,000 feet—​ [4,500 meters]

Potosí, Bolivia

13,700 feet [4,180 m]

Puno, Peru

12,549 feet [3,826 m]

Mount Fuji, Japan

12,387 feet [3,776 m]

La Paz, Bolivia

11,900 feet [3,625 m]

—10,000 feet—​ [3,000 meters]

Trongsa Dzong, Bhutan

7,867 feet [2,398 m]

Mexico City, Mexico

7,347 feet [2,239 m]

Mount Washington,

New Hampshire, United States

6,288 feet [1,917 m]

Nairobi, Kenya

5,495 feet [1,675 m]

Denver, Colorado, United States

5,280 feet [1,609 m]

—5,000 feet—​ [1,500 meters]

—Sea level—​

[Picture on page 10]

La Paz, Bolivia 11,900 feet [3,625 m]

[Picture on page 10]

Johannesburg, South Africa 5,740 feet [1,750 m]