Marmite could be illegal in Denmark if it fails to meet safety requirements.
By law, Danish authorities must give their approval for food fortified by vitamins or minerals before sale.
The Danish Food & Veterinary Administration says products with such additives need to be assessed for any potential dangers.
The procedural checks needed before a final decision is reached could take up to six months.
Denmark has previously banned several popular items, including Ovaltine and some breakfast cereals.
The BBC reports a shop in Copenhagen was recently asked to remove its supplies of Marmite following a phone call from Danish authorities.