Chewing coca leaves is not straightforwardly healthy or harmful. The practice delivers a mild stimulant effect along with notable nutrients, but it also introduces cocaine into your bloodstream at low levels and may impair cognitive function over time. In October 2025, the WHO concluded that traditional coca chewing does not pose major public health risks, while also noting that long-term safety data remains limited.
What Happens When You Chew Coca Leaves
When you chew a wad of dried coca leaves (typically 5 to 10 grams), cocaine is absorbed through the lining of your mouth and enters your bloodstream almost immediately. Plasma concentrations peak somewhere between 10 and 150 nanograms per milliliter within about 20 minutes to two hours. For comparison, snorting a line of cocaine produces blood levels roughly 10 to 50 times higher. The cocaine from chewed leaves has an elimination half-life of one to two hours but can be detected in blood for over seven hours.
Coca leaves contain between 0.11% and 1.02% cocaine by dry weight, along with smaller amounts of related alkaloids. The slow, steady absorption through cheek tissue creates a gentle stimulant curve rather than the sharp spike associated with processed cocaine. This is the key pharmacological distinction between traditional chewing and recreational drug use.
Nutritional Content of Coca Leaves
Dried coca leaves are surprisingly nutrient-dense. Per 100 grams, they contain roughly 20 grams of protein, around 1,000 milligrams of calcium (nearly a full day’s requirement), 29 milligrams of iron (well above the daily recommendation), and significant amounts of magnesium and zinc. They’re also rich in beta-carotene, which your body converts to vitamin A, and contain vitamin E.
These numbers look impressive on paper, but context matters. A typical chewing session uses 5 to 10 grams of leaves, not 100 grams, and much of the leaf material is spit out rather than swallowed. So the actual nutrient intake from a chewing session is a fraction of those per-100-gram values. Coca leaves can contribute to the diet of Andean populations, but they’re not a replacement for whole meals.
Effects on Physical Performance and Energy
The most consistently reported benefit of coca chewing is improved physical endurance, which is why Andean laborers, miners, and farmers have relied on it for centuries. Studies on indigenous chewers at high altitude found that coca elevated internal body temperature and increased stamina during physically demanding tasks. Most users report reduced sensations of fatigue, hunger, and thirst.
The mechanism appears to involve how your body burns fuel. Research suggests coca compounds block a step in the normal glucose-burning pathway, pushing your muscles to rely more heavily on fat oxidation for energy. This metabolic shift could explain why chewers feel they can sustain physical effort for longer periods. It also helps explain the next finding.
Blood Sugar Regulation at High Altitude
A study of 28 Aymara adults on the Bolivian Altiplano found that coca chewers maintained more stable blood sugar during a glucose tolerance test compared to non-chewers. The non-chewers experienced a significant blood sugar dip at the two-hour mark, a common reactive hypoglycemia response. Coca chewers did not experience this drop, likely because coca’s metabolites counteract insulin’s effects and keep more glucose available in the bloodstream.
At high altitude, where the body already struggles with lower oxygen levels and is prone to hypoglycemia, this glucose-stabilizing effect could be genuinely protective. Whether this translates to a meaningful benefit at lower elevations, where hypoglycemia is less of a concern, is unclear.
The Altitude Sickness Question
Coca tea and leaves are widely offered to tourists arriving in high-altitude Andean cities like Cusco and La Paz, marketed as a remedy for altitude sickness. The scientific evidence here is less supportive than the reputation suggests. One controlled study found no significant differences in oxygen saturation, blood pressure, or pulse rate between coca chewers and non-chewers at altitude. The leaves did not improve how efficiently the body used oxygen.
What coca likely does is mask the discomfort of altitude sickness, reducing the perception of fatigue and nausea through its mild stimulant and appetite-suppressing effects, without addressing the underlying oxygen deficit. This is a meaningful distinction: feeling better and being physiologically better are not the same thing.
Cardiovascular Effects
Coca chewing raises your heart rate. In one study, resting heart rate jumped from about 60 beats per minute to 76 beats per minute during a chewing session. During exercise, chewers showed both higher heart rates and higher mean arterial blood pressure compared to non-chewers. For a healthy person doing occasional chewing, this is comparable to drinking a strong cup of coffee. For someone with existing heart conditions or high blood pressure, regular stimulant-driven increases in cardiovascular load are worth considering.
Cognitive Function Over Time
This is where the health picture gets less favorable. Short-term, coca chewing delays reaction time and reduces accuracy on tasks, similar to the effects of low-dose cocaine. More concerning are the long-term findings. Assessments of habitual chewers found they scored lower across eight different tests measuring attention, memory, abstract reasoning, and learning compared to non-chewers.
Researchers interpret these results as evidence that chronic coca chewing produces lasting changes in brain function that show up as cognitive deficits. The word “chronic” is key here. These studies looked at people who chewed daily for years or decades, not occasional users. Still, this is the most significant potential health downside identified in the literature, and it’s not well known outside of academic circles.
Legal Status and the WHO’s Position
Coca leaf remains under Schedule I of the 1961 Single Convention on Narcotic Drugs, meaning it is internationally controlled. In late 2025, the WHO’s Expert Committee on Drug Dependence completed a comprehensive review and recommended keeping coca leaf at this level of control. The committee acknowledged that traditional chewing and coca tea do not pose major public health risks, and it recognized the leaf’s cultural and therapeutic significance for Indigenous communities.
Crucially, the WHO did not recommend moving coca to the strictest control level, which would have prohibited traditional use entirely. National exemptions for traditional and cultural use in producing countries like Bolivia, Peru, and Colombia remain in place. Outside these countries, coca leaves are illegal in most jurisdictions, regardless of their traditional form.
The Bottom Line on Health
Coca leaf chewing occupies an unusual space: it delivers real nutritional value and measurable physical endurance benefits, particularly in the high-altitude environments where it has been used for thousands of years. It stabilizes blood sugar under hypoxic conditions and provides a mild, sustained stimulant effect without the intensity or crash of processed cocaine. At the same time, it does put cocaine in your blood (at low levels), raises heart rate and blood pressure, and appears to erode cognitive sharpness with years of daily use. The WHO’s summary captures the ambiguity well: not a major public health risk, but not enough long-term safety data to call it definitively safe either.