The eminent Muslim scholar and renowned Da`iyah, Sheikh `Abdel Khaliq Hasan Ash-Shareef, states: “There is no doubt that even if Islam has permitted eating of what is on earth with the exception of anything regarding which there is a textual proof prohibiting it, Muslim scholars differentiate between what is generally permissible and what is permitted for a certain person.
Although Almighty Allah permits eating what is on earth with the exception of anything regarding which there is a textual proof prohibiting it, but being permitted for man is decided based on what may result from eating it. If it is proven that a certain food may cause harm to a certain person, then in such a case it would not be permissible. For example, sweets and candies are permitted for eating but they are not permitted for a diabetic person. So, the ruling of permissibility changed because eating such a food or candies may cause harm to this diabetic person. The same ruling applies to any kind of food that may result in causing harm to the person eating it.
Therefore, certain kind of foods may be prohibited on condition that there is certainty about its causing harm and this harm is not imagined as we should not expand in narrowing what Allah permits for His servants based on doubt or uncertainty.