It isn't any lower in syns as I think they have to add more fat to stabalise the lack of sugar. The sugar substitute is also a mild laxative, so it would be better not to eat too many!!!!!
If you are diabetic, thorntons do a range:
Diabetic Dark Chocolate Bar, 75g bar (17½ syns) Diabetic Luxury Chocolates, Milk/Dark, 28g (5½ syns) Vanilla Diabetic Toffee, 28g (6 syns)
If you aren't diabetic, I would just stick with the regular stuff!
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