My patients often come to see me armed with blood tests ordered by their local G.P. The blood tests have been reported as ‘normal’ but my patient does not feel well – how can this be explained? There are a few reasons why this can happen. Firstly, ‘ordinary’ G.Ps are taught that all numbers in a range are ‘equally good’. The reference ranges are taken from patient results and out of one hundred results, the top five and bottom five are excluded, leaving a reference range of ninety percent. But this does not represent good or optimal, particularly when you realise that the blood tests to achieve this reference range are performed on unwell people!!
For example, if the range of ferritin (iron stores) is 15-200, then any result between these two figures is acceptable – this is nonsense!!
A level of 15 is inadequate and a person with such low iron will undoubtedly feel tired. I do infusions of iron in my surgery and the improvement in energy when someone has an iron less than 50 is remarkable. Similarly, the range for Vitamin D is 51-140 – but at 50 the patient is at risk of rickets, so just being slightly over the lowest number in the range cannot be optimal. Always question your doctor about what would be OPTIMAL rather than whether something is just ‘in the range’.
Another problem with ‘ordinary’ G.P. blood tests is that tests may not probe deeply enough to give enough information. Thyroid tests are a good example, where ordering ‘thyroid function tests’ will provide the G.P. with just thyroid stimulating hormone, which is a pituitary hormone, not secreted by the thyroid gland at all. Thyroxine, and certainly free T3 and reverse T3 are vital to make an accurate assessment, and the G.P. has to specifically request them.
The third challenge that G.Ps have is acquiring adequate knowledge of available tests. There are many blood, saliva and urine tests which I utilise in my practice which medical centre G.Ps may be unfamiliar with. They provide valuable and sometimes vital information and inform treatment protocols. The internet can provide a lot of information about available tests so that patients can arm themselves before visiting their G.Ps.
Remember, when it comes to blood tests – ‘in the range’ does not mean OPTIMUM health!!!