- Zincatest is a simple non-invasive test, which gives an indication of zinc status - Zincatest can also be given as a zinc supplement - Ideal for those who find tablets and capsules difficult to swallow Up to one in three adults in the UK receives less than the Reference Nutrient Intake (RNI) for zinc. This is largely a result of refining processes which remove up to 90% of the available zinc content from cereal grains, along with the trend to eat less animal-derived protein.