catstail - if you Google 'how many carbs in a Magnum' this is what you get:
Food Item: Magnum
Food Quantity: 1 Magnum
Carbs: 25g
Dietary Fiber: 0g
Net Carbs: 25g
Magnum Ice Cream and Diet
Not permitted on low carb diets, ice creams (like Magnum Ice Cream) are typically high calorie foods with no dietary fiber and not much nutrition. Very roughly, water accounts for about 60 percent of ice cream weight, protein about 4 percent, fat about 10 percent and carbohydrate (mostly sugar) about 25 percent. Because sugar is one of the major ingredients, ice cream can be high on the Glycemic Index, which means it can cause a rapid rise in blood-glucose levels, leading to excessive insulin production and a sudden drop in blood sugar. Other ice creams can be high in fats, including saturated fat. Bottom line: whether or not you are into low carb dieting, if you want to lose weight, manage your blood sugar levels and stay healthy, keep your intake of ice-cream and other sugary-carb foods to a minimum.
Honestly - don't do it to yourself! You may have got away with it this week, but you certainly won't lose weight if you carry on with the self-sabotage.
Ultimately it's up to you. If you want to lose weight ... 