I am not a nutritionist but after my own recent visit to one, due to health problems, I do know that craving sugar is a massive indicator of low blood sugar level. Ironically, eating sweet things means your blood sugar will rise and then fall very swiftly afterward, leading to further cravings, so in fact eating sugary food is the worst possible thing you can do if you suffer from low blood sugar!
You simply won't crave sweet things if you eat regularly and keep your blood sugar stable. To do this you need to eat lower and medium GI foods at very regular intevals, of say two to three hours, all day, rather than eating higher GI food but not with large periods of time elapsing betwen snacks. Find the Glycemic Index on line:
http://www.glycemicindex.com/ and look at the foods you should be eating little and often. It works.
You will lose your sweet tooth too, because it is a learned response anyway - we are not born liking sweet things. The only reason we learn to like sugar is because sugar companies have major deals with nearly all food manufacturers so that there is white refined sugar in nearly every non-homemade food that most people eat - all breads, almost all breakfast cereals (Tesco do not sell one single whole grain breakfast cereal without sugar in it - even their 'no added sugar' muesli contains dried fruit which is coated with sugar - I had to go to a health food shop), baked beans, pickles and relishes, ready made pasta sauce, nearly all ready-meals etc.
If you follow a lower GI diet and stick to wholegrain foods (ie. wholemeal breads, wholemeal pasta, long grain brown rice, wholegrain breakfast cereals such as shredded wheat or whole oats have not only more fibre but also less sugar in them - a lower GI and calorific value) you will lose weight without being hungry, simply because you will be eating food all day, but with a much lower calorie content. You will avoid feeling like you need a sugar fix because your blood sugar will be more stable with eating lower sugar and wholegrain foods.