Milky Ways are 3.5g of fat for the bar, but they're not within the 5% fat rule as the bar is not 100g in weight, Milky Ways are actually 16% fat.
The thing with the tablets though is that it's all trial and error, and what might give someone a side effect, it might have no effect whatsoever in someone else. Things like walkers baked crisps are great, but they're actually over the 5% rule too ( they're between 7 and 8 % fat), so again some people might get a side effect, some one else might not.
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