A quick note about tuna. Tuna makes a quick and easy snack, but you need to be careful when choosing canned tuna. I suppose it is the Dukan principles, avoid processed food, oils and buy basic ingredients and jazz it up yourself using Dukan-compliant ingredients.
Tuna canned in springwater is a better choice than tuna in brine as it minimises your salt consumption (which can lead to fluid retention). In general, I prefer the taste and appearance of Sirena branded tuna, and their springwater tuna is no exception.
Lately, for lunch, I have been draining a 185 g can, splitting it bewteen two screw top containers and adding natural no fat yoghurt (Tamar no fat is my favourite, but not available this week, so a small pack of Black swan was a substitute), lemon juice and pepper, and stirring it up. Works well. I have been taking one for lunch and storing the other for the next day.
