The accuracy of intolerance tests is difficult to calculate. It would entail people adhering to a strict elimination diet for several weeks or months. Unfortunately, that information isn’t available. When it comes to understanding 5Strands accuracy, there are two general things to know:
Negative results are accurate and reliable. In other words, having a negative result, but actually being intolerant, is highly unlikely. This is why 5Strands recommends eating only foods you have a negative result for as the basis of your elimination diet.
Allergy/intolerance tests tend to have high false-positive rates, though, up to 50-60%. This would mean having a positive result, but actually having no reactivity to the substance. That’s why it’s ok to try some of the foods again in a couple of months.
The other thing to consider about the 5Strands hair test is the testing method. 5Strands uses (and stands behind the accuracy of) bioresonance testing. It’s highly regarded by some, and called “pseudoscience” by others. Bioresonance testing is an alternative medicine practice based on analyzing energy patterns and wavelengths transferred between all living matters.