Standing at the base of Vinicunca, more commonly known as Rainbow Mountain, the air already feels thin. The vibrant stripes of mineral-rich sediment stretch upward into the Andean sky, a sight that draws thousands of hikers each year. But what many don’t anticipate is the sheer physical challenge of ascending to 5,000 meters above sea level. At this altitude, every step feels heavier, every breath shorter. That’s where the debate over oxygen cans comes into play—a small, portable lifeline that can make or break the experience.

The journey to Rainbow Mountain begins long before the first step on the trail. Most hikers depart from Cusco, a city already sitting at 3,400 meters, where acclimatization is crucial. Even those who spend days adjusting may find themselves gasping for air during the steep, three-hour climb to the summit. The locals, of course, move with an ease that seems almost superhuman, their lungs adapted over generations to the thin air. For visitors, though, the struggle is real. Headaches, dizziness, and nausea are common companions on this trek.

This is where oxygen cans enter the picture. Sold in shops throughout Cusco and even by vendors at the trailhead, these cans promise a quick boost of oxygen to combat altitude sickness. They’re lightweight, easy to use, and marketed as a must-have for high-altitude hikes. But do they live up to the hype? The answer isn’t straightforward. Some hikers swear by them, claiming the cans provided immediate relief when they felt on the verge of collapse. Others argue they’re little more than a placebo, a psychological crutch for those unprepared for the demands of the climb.

The science behind portable oxygen cans is simple: they deliver a concentrated burst of oxygen, typically lasting a few minutes per use. For someone experiencing acute altitude sickness, this can be enough to stabilize their condition and allow them to continue. However, experts caution that they’re not a substitute for proper acclimatization. Relying solely on oxygen cans without giving your body time to adjust is a risky gamble. The best approach is a combination of gradual altitude exposure, hydration, and—if needed—supplemental oxygen as a temporary aid.

On the trail, the sight of hikers pausing to take deep pulls from their cans is common. The cans themselves are unassuming, often resembling small aerosol containers with a plastic mouthpiece. Using one is intuitive: press the nozzle, inhale deeply, and wait for the effects. For some, the difference is immediate—a sudden clarity, a return of energy. For others, the relief is subtler, a slight easing of the pounding headache or the tightness in their chest. The variability in responses highlights how individual altitude tolerance can be.

One factor often overlooked is the psychological benefit of carrying oxygen. Knowing it’s there, tucked into a backpack, can provide a sense of security that alone helps mitigate anxiety. Altitude sickness is as much a mental battle as a physical one, and the reassurance of having a backup can be invaluable. This is particularly true for those attempting the hike without a guide, where the safety net of experienced support is absent.

Yet, there are drawbacks. Oxygen cans aren’t cheap, and their effects are fleeting. A single can might provide only five or six uses, hardly enough for the entire trek. Some hikers report feeling dependent on them, reaching for a boost at the slightest hint of discomfort rather than pushing through. There’s also the environmental concern—discarded cans littering the trail, a growing problem as tourism to Rainbow Mountain surges.

For those considering whether to bring oxygen cans, the decision ultimately comes down to personal preference and preparedness. Seasoned hikers with prior high-altitude experience might forego them entirely, relying instead on slow pacing and rest breaks. Beginners or those prone to altitude sickness, however, may find them a worthwhile investment. The key is to view them as one tool among many, not a magic solution.

Rainbow Mountain remains one of Peru’s most breathtaking destinations, a place where the earth itself seems painted in surreal hues. The challenge of reaching its summit is part of what makes the experience so rewarding. Whether with or without oxygen cans, the journey demands respect for the altitude and an honest assessment of one’s limits. After all, the view from the top isn’t just a spectacle of nature—it’s a testament to perseverance.