I have been obese for many years and also now if I do not pay attention to what I eat I gain weight immediately.

Eventually I have learned to control exactly what I eat, in order to control my weight, but I no longer find this difficult, mainly because normally I eat only what I cook myself (with the exception of trips away from home).

When I experiment how to cook something that I have never cooked before, after I reach a stable recipe with which I am content, I measure carefully every ingredient, either with digital kitchen scales or with a set of volumetric spoons. Then I compute the relevant nutrient content, e.g. calories, protein content, fatty acid profile, possibly some vitamin and mineral content, in the cases when there exists a significant content of that.

While I do this carefully the first time and I record the results, whenever I cook the same later I do not need to pay attention to this, because I already know the nutrient content, so summing for all the portions of food that I plan to eat in that day I can easily estimate the daily intake for everything.

The essential change in my habits that enabled me to lose the excessive weight was that in the past I was eating without paying attention to quantity, until I was satiated, while now I always plan what amount of food I will eat during a day and I always cook the food in portions of the size that I intend to eat, which is always the same for a given kind of food, so I no longer have to repeat any of the computations that I have made when I have determined for the first time a recipe.

In a recipe, things like spices can be ignored, because they add negligible nutrients. Even many vegetable parts, like leaves or stalks, or even some of the roots or of the non-sweet non-fatty fruits, may be ignored even when used in relatively great quantities, because their nutrient content is low. So such ingredients may be added while cooking without measuring them.

For many vegetables and fruits, which are added to food as a number of pieces, I do not measure them when cooking, but when buying. I typically buy an amount sufficient for next week, which is weighed during buying. Then I add every day a n approximate fraction of what I have bought, e.g. 1/7 if used for cooking every day. Then for estimating the average daily intake, I divide by 7 what I have bought for the week.

What cannot be ignored and must always be measured during cooking, to be sure that you add the right amount, are any kinds of seeds or nuts or meat or dairy or eggs, anything containing non-negligible amounts of starch or sugar, any kind of fat or oil or protein extracts. Any such ingredients must always be measured by weight or by volume, to be sure that you add the right amount to food.

Nevertheless, measuring the important ingredients adds negligible time to cooking and ensures perfectly reproducible results.

I eat only what I cook myself and I measure carefully everything that matters, but the total time spent daily with measurements is extremely small. I doubt that summing all the times spent with measuring food ingredients during a whole day can give a total of more than one minute or two. Paring and peeling vegetables or washing dishes takes much more time.