What is DNP (dinitrophenol)?

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DNP is an industrial chemical used in dyes and explosives; it is a poison that makes cells leak their energy as heat, dangerously raising body temperature.

What is DNP (dinitrophenol)?
A chemical sold as a 'fat burner'
Online, a substance called 'DNP' is sold as if it were a fat-burning drug. But DNP is an industrial chemical that no country has approved as a human medicine. What exactly is it, and why is it so dangerous?
In short
An industrial chemical used in dyes and explosives
DNP is short for 2,4-dinitrophenol, a yellow chemical used to make dyes, wood preservatives, explosives and more. When people swallow it, they lose weight, but their body temperature can rise out of control and they can die.
Background
ATP, the cell's energy packet
The cells in our body store the energy from food in a substance called ATP and then use it. ATP is an energy packet that cells can use right away, and it supplies most of the energy cells need to do their work. ATP is made mainly in tiny structures inside cells called mitochondria.
What it does in the body
Energy leaks out instead of being stored in ATP
Mitochondria move the energy from food into ATP. DNP punches a hole in this process, so the energy cannot be stored in ATP and leaks out as heat. The fuel gets used up, yet the cell ends up short of ATP to use. Scientists call substances that make energy leak this way 'uncouplers'.
Why weight drops
The body burns more fuel to make up for missing ATP
When ATP runs short, the body burns more fat and carbohydrate. That is why weight drops quickly. But much of the burned energy becomes heat, so body temperature rises, and if the body cannot shed this heat, its temperature climbs out of control.
History
A diet drug of the 1930s
In 1933, researchers at a US university reported that taking DNP made people lose weight, and DNP was soon sold as a diet drug without a prescription. But cases of cataracts, where the inside of the eye turns cloudy and vision blurs, and deaths kept coming. In 1938 the US declared DNP 'extremely dangerous and not fit for human consumption'.
It came back
Sold illegally online
In recent years DNP has been sold illegally online for dieting and bodybuilding. In the 2010s, DNP poisoning cases reported to poisons centers in many countries rose sharply. The World Anti-Doping Agency, which decides which drugs are banned in sport, treats DNP as a substance not approved as a human medicine and bans it at all times.
Signs of poisoning
High fever and a racing heart
The typical signs of DNP poisoning are high fever, a fast heartbeat, heavy sweating and fast breathing. The skin, the whites of the eyes and the urine can turn yellow. As body temperature keeps rising, the muscles stiffen and the heart and blood vessels give out, and the person dies.
Deaths
More than one in ten known poisoning cases died
Among DNP poisonings reported to poisons centers in many countries, more than one in ten of the cases with a known outcome ended in death. Poisons center data from the UK and the US also showed similarly high death rates. Medical records have noted deaths from DNP steadily since the early 1900s.
A real case
Two pills bought online
A healthy young woman came to the emergency room after taking two DNP pills she had bought online to lose weight. Doctors rushed to cool her body, but her temperature kept rising until it reached 41.5 degrees Celsius. In the end her heart stopped and she could not be revived.
Common myth
Does it burn only fat?
No. DNP is sold as a 'fat burner', but it does not pick out fat to burn. It makes cells leak their energy as heat, so the body burns more carbohydrate too, and the heat produced dangerously overheats the body.
Summary
A poison that makes energy leak as heat
DNP is an industrial chemical used in dyes and explosives that makes cells' energy leak out as heat instead of being stored in ATP. It is not a drug that burns only fat but a poison that raises body temperature out of control, and poisoning can kill. Related terms: ATP, mitochondria, clenbuterol.