Good news if you already consume tuna on a regular basis, itâs high in niacin compared to many other foods. Itâs also a good source of omega-3s as well as protein. There are concerns about the mercury content, so you may not want to rely on tuna for your daily niacin consumption, but itâs nice to have once in awhile. Serving Size (100 grams), Niacin (5.8milligrams), 184 calories.
At the end of the spinal column is the coccyx or tailbone. Most people have 33 vertebrae in total, although there may be 32 or 34. Variations are usually found in the lumbar or sacral regions.
Here you can see the vertebral bodies with the discs in the front of the spine and the facets in the rear. The nerve roots exit through the sides of the spine. (Click to Enlarge Image) This is a side view (sagittal) MRI of a large disc herniation in the cervical spine (neck). The arrow points to the herniation.