The actual studies done on DNP, had obese subject on DNP for months at a time. However this was at a low dose, I believe around 200mg per day give or take. The doses used to lose lots of fat quickly are generally much higher and present many more side effects, making it very hard to stay on for extended periods of time. Due to the extreme nature of the drug I would personally not reccomend going over 10-12 days at a high dose (400-600mg).
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