Aluminum

Aluminum

Aluminum is a metal used in some vaccines in the form of aluminum salts (such as aluminum hydroxide or aluminum phosphate). These compounds are engineered to be poorly soluble so they remain in the body after injection. In vaccines, aluminum functions as an adjuvant, meaning it enhances the immune response to the antigen.

Unlike dietary aluminum, injected aluminum bypasses normal digestive processing and enters the body directly through muscle tissue. From there, it can be transported by immune cells and distributed to organs and tissues. This difference in form and route of exposure is central to how aluminum behaves biologically in the context of vaccination.

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