How to calculate Syns

[bilsat]

Is there a formula to calculate Syns, if so what is it.
An example I have is:

Caleries per 100g= 139
Protein per 100g= 19.4
Carbs per 100g= 9.5
Fat per 100g= 2.6

Syns = 3.5 syn

So how is it worked out?

 

[ruthiebusybee]

It depends on whether there is free food allowance so you can't really work it out, as it will depend on many factors in that case.

If there is no free food allowance, general rule of them is 1 syn per 20 calories.