NUT incorporates an empirical equation from Dr. William Lands that relates polyunsaturated fatty acid consumption in a low-fat diet to resulting percentages of Omega-6 highly unsaturated fatty acids in tissue phospholipids over the long term. For a low-carb/high-fat diet, this equation overstates the amount of Omega-3 required. The NUT reference values are refigured every time you show an analysis screen and they take into consideration all the fatty acids in the diet.
The scatterplot at the right shows actual levels of highly unsaturated fatty acids in tissue phospholipids for a population sample, with the first number of the "Omega-6/3 Balance" value indexed on the bottom axis.
The following graph is meant to demonstrate that comparable results can be achieved by either adding Omega-3 or reducing Omega-6 in accordance with varying cultural food customs. The rationale is that excessive Omega-6 metabolites can cause an exaggerated inflammation response that leads to tissue damage and cardiovascular events which can be prevented by allowing Omega-3 to outcompete Omega-6 for positions in the tissue phospholipids.
The graph below shows tissue concentrations of Omega-6 highly unsaturated fatty acids plotted against population cardiovascular mortality.
Here is a nice ecological overview book chapter by Dr. Lands for the biologically-literate. And here is an excellent and understandable review by Dr. Lands with enough depth to further your comprehension of the importance of these fatty acids to how well you feel physically and mentally.
Experiment with various "Omega-6/3 Balance" values to get the main benefit of Omega-3, which is a lack of physical and mental suffering.