Warnings issued over deadly DNP 'diet drug'

“Tragedy of the gifted rugby player, 18, who died after buying deadly 'fat-burning' pills online,” the Daily Mail reports. It is just of one of many newspapers and websites who have reported on the death of Chris Mapletoft, who died after taking 2,4-Dinitrophenol (DNP). This is a banned substance that has been marketed on the internet as a "wonder slimming aid".

DNP has also been linked with the deaths of students Sarmad Alladin and Sarah Houston earlier in 2013.

What is DNP?

DNP is a combination of compounds that was widely used during the early 20th century in a range of industrial processes.

In 1933, an American researcher discovered that when taken by humans, DNP dramatically speeds up the metabolism leading to rapid weight loss. It was subsequently marketed as a weight loss drug. It was quickly withdrawn from the market, however, after it was found to be highly toxic, causing significant side effects and in some cases, deaths.

In 1938 the American Food and Drug Agency issued a statement saying DNP was “extremely dangerous and not fit for human consumption”.

It appears that DNP has becoming increasing popular during the last decade among bodybuilders for its "quick-fix" ability to lead to rapid weight loss. Presumably this information was spread both by word-of-mouth as well as via internet forums and message boards.

Why is DNP so dangerous?

One of the risks of DNP is that it accelerates the metabolism to a dangerously fast level. Our metabolic system operates at the rate it does for a reason – it is safe. Speeding up the metabolism may help burn off fat, but it can also trigger a number of potentially dangerous side effects, such as:

  • fever
  • dehydration
  • nausea
  • vomiting
  • restlessness
  • flushed skin
  • excessive sweating
  • dizziness
  • headaches
  • rapid breathing
  • rapid or irregular heartbeat

The combination of these side effects can have an extremely damaging effect on the body and can result in coma and, as we have seen, death.

Long-term use can lead to the development of cataracts and skin lesions and may cause damage to the heart and nervous system. There is also evidence from animal studies that DNP is carcinogenic (cancer causing) and increases the risk of birth defects.

Is DNP legal?

No. It is illegal to sell DNP as a weight loss drug and doing so could place you at risk of criminal sanctions.

What is being done about DNP?

The Food Standards Agency (FSA) is actively working with the police and local authorities to stamp out the illegal sale of DNP to consumers, focusing on stopping internet sales. The FSA is supporting local authorities to help with this work.

However, many websites that offer DNP for sale are based in foreign countries meaning that cutting supply of the drug is difficult. Despite the best efforts of the UK authorities, people determined to buy DNP can do so with ease.

Because it is so easy to access supplies, there is only so much the authorities can do to protect you. It takes only a few seconds to find sites selling DNP on the internet. Some of these sites offer such illegal products alongside perfectly legitimate weight loss drugs, which adds to the potential for confusion.

Personal responsibility must play a part, as Rod Ainsworth, FSA director, said: "It’s really important that people understand quite how dangerous DNP is. We have been working hard to raise awareness of the dangers of DNP and to encourage people to let us know if they are sold products containing this chemical. If people are offered DNP they should not take it and should instead contact the FSA or their local authority."

Anyone with information about the illegal sale of DNP should report this by email to and the police.

NHS Attribution