What can a blood test pick up can it pick anything serious up

A blood test, ordered by your doctor, will alert him to possible conditions that might occur, such as prediabetes, and autoimmune diseases. However your doctor can order up a general blood test and unless he thinks there is something wrong in these areas, will order additional categories.

Can it pick up cancer

Some doctors order "cancer markers" or "tumor markers" to detect possible cancer activity in the body. If cancer is present, it will usually produce a specific protein in the blood, that can serve as a "marker" for the cancer. CA 15.3 is the name of a protein used to find breast and ovarian cancers. CA125 may signal ovarian and breast cancer recurrence. TRU-QUANT and CA 27.29 are other examples of proteins associated with breast cancer, which your doctor may test for. CEA (carcinoembryonic antigen) is a marker for the presence of colon, lung, and liver cancers. This marker may be used to determine if cancer has spread to other areas of the body.