The past week has been filled with spectacular victories and heartbreaking failures for Everest climbers. Our favorite guy on Snapchat, Cory Richards, made his first summit without supplemental oxygen Tuesday morning. Lhakpa Sherpa broke her own record for the most summits made by a woman, bagging her seventh on Friday. But many climbers’ dreams of reaching the top of the world’s tallest mountain have been squandered by altitude sickness, frostbite, and death. Four climbers have died in the span of four days on the mountain, including Maria Strydom, an Australian climber and lecturer at Monash Business School in Melbourne.
Strydom, a vegan, set out to summit Everest as a demonstration that a vegan diet is not a handicap for extreme athletics. But following her death — which was attributed to high-altitude pulmonary edema (HAPE), which caused fluid to build up in her brain — many questioned the message Strydom was attempting to validate.
But there's just no connection between high-altitude pulmonary edema and any kind of diet. “I can’t imagine that a vegan diet is to blame,” says Dr. Robert Roach, director of the Alpine Research Center in Aurora, Colorado. “It is more about whether or not you’re eating enough calories — of any sort — while climbing at high altitudes. Pulmonary edema can occur when fluid, instead of air, accumulates in the lungs. This exact thing happens in high altitudes when the rate of ascent, the altitude attained, and your level of physical exertion at these altitudes can contribute to the illness.
That's not to say that a bad diet isn't a risk on Everest. The heavy exercise, heat generation, and acclimatization that summiting Everest entails requires a huge energy expenditure. You have to replace those calories — whether it’s with nuts or meat doesn’t matter. What matters is caloric intake.”
Just as nutritional practices for marathon running has changed over the decades (we now know that you don’t need a huge pasta dinner before a race, and that Paleo dieters can successfully run a 26.2), practices for proper fueling during extreme outdoor expeditions are highly individualistic. So instead of focusing on what climbers are consuming, it’s more important to target the quantity and scheduling of food to ensure safety and good health at high altitude.
“Tolerability of specific diet is extremely individual,” Roach says. “The priority is knowing how many calories you need and eating those calories on a proper schedule. When you are on a mountain like Everest and you are getting in at 6 p.m. and beginning a summit attempt at midnight after spending the night in a windstorm without getting any sleep, it’s easy to find yourself in a situation where you go hours and hours with little calorie intake and no water. That’s the recipe for disaster.”
Roach suggests that the best nutritional plan of action for mountaineers is using the buddy system for meal scheduling. At high altitudes, appetite is suppressed and climbers commonly experience short-term memory loss, making it easy to not eat enough or to forget the last mealtime. Research shows that the most successful expeditions have been those where climbing partners encourage one another to eat beyond their natural cravings for food. “You can find yourself at an energy deficit very easily, which is why it’s crucial to go into a climb knowing how many calories you need to be consuming a day, and with a scheduling plan to take in those calories that you can hold yourself and your team to,” Roach says.
It’s easy to plan for, but at 29,000 feet, nothing is easy. “The top of Everest is unlike any place you would visit regularly. Everything you do is a challenge and everyday routines – such as eating – become tasks. You get behind on eating, and you get behind on keeping yourself alive. It’s not like going to Aspen and getting a headache.”