Answered by Shaykh Yusuf Weltch
What is the verdict for a sister who has an issue of her gums bleeding when she brushes her teeth. Her gums stay red and inflamed for hours and even days and during that time there may be some blood around the gums but it doesn’t flow out. If she presses a tissue next to her gums, she sees that some traces of blood are on the tissue. While she is working on treatment, how should she eat food when one is not allowed to consume blood?
In the Name of Allah, the Most Merciful and Compassionate
Constant Blood in the Gums
If one is constantly dealing with blood in the gums and the blood does not flow, but merely gatherings around the gum lining, this blood does not invalidate the ablution (wudu) and is therefore, not impure at all. Only flowing blood is seen as impure. [Tahtawi/Shurunbulali, Hashiyat Maraqi al-Falah]
That said, the taste of blood while eating is pure and permissible.
Hope this helps
Allah knows best
[Shaykh] Yusuf Weltch
Checked and Approved by Shaykh Faraz Rabbani