Just found this...
Syns
Syns are everything that don't fit into the category of free food or healthy extra - it's not just "treats" like chocolate, wine, sweets, biscuits etc.(although these do have a syn value). It can be things like gravy, butter, stuffing, additional Healthy Extra's like cheese, milk and bread. Syns are there so you don’t feel deprived or have to cut anything out. We all like a nice treat, whether it be a big bar of chocolate or gallons of gravy on our Sunday dinner, but too much causes weight gain.
Everything that isn’t a Free Food or used as a Healthy Extras has a syn number; the number depends on how calorie dense it is. I.e. how many calories it has for its volume, and how quickly it turns to energy. Don’t think that because of the name all syns are bad foods, as mentioned above it could be anything. For example a Morrisons Eat Smart French-Style vingerette isn’t a ‘bad’ food – but it’s 1/2 syn per tbsp. Also don’t get tripped up by fat-free, low calorie or diet foods (especially yoghurts). They might be low in fat, but high in sugar, or low in sugar but high in fat, or they might be low in sugar, low in fat, low in taste but high on syns – always check.
The reason peoples weight loss slows down, or they start to gain when the try not to have any syns, is because the body isn't getting enough calories to function and goes into starvation mode and hold on to everything - what you've got and what you give it.
Please use your syns, they are there to be used and that way you won't feel deprived like you might on other plans. I didn't use any of my syns in my first week and didn't lose any weight, the following week I used 10-15 a day and lost 4lbs the following week.... the plan works trust me

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