Re 'deserving' lunch.
I think there's a few things to unpack there.
I think we tend to eat today through habit more than anything because of an abundance and easy access to food.
There is a shop on every corner selling it and we can store it more easily. It also has long shelf lives. In the past, you couldn't just help yourself to food on every single hunger pang. Because you didn't have any (your cupboards were bare for whatever reason) and it wasn't easy to just get more immediately. You had to wait.
This means the ideas of self control and advertising are very much linked.
This ties in with the social convention of having 3 meals a day which is very modern. No we do not NEED to have lunch. We want lunch. We don't ever deserve lunch. Lunch is a desire in our modern world. We only need food if we are hungry. We have forgotten this. Instead we timetable food rather than deciding whether we need it.
This ties in with the concept of portion size too. It's fascinating how attitudes to clearing the plate are cultural and change around the world. The British attitude is we much always clear out plate - so this comes ahead of whether we are hungry or not. This is a hang over from food shortages in the past. If you go to the US, leaving food on the plate is much more accepted and normalised. Then we have how plate sizes have changed. It never fails to amaze me when I visit friends how attitudes to food are so often linked to the size of plate people have. This is where psychology comes in. People eat with their eyes and their cultural attitudes. So people fill a larger plate more because 'it looks right' and then clear the plate. Simply switching your plate size down can reduce your calorie intake and is a 'diet' plan which is one of the most successful and sustainable. Simply because you don't have to change what you eat.
This also brings me to quantity of food. People vastly over estimate how much they should be eating. When you look at how much was recommended daily in terms of the size of the amount of meat / cheese etc in the 40s, 50s, 60s its vastly different to what it was. People have no idea. Then you have things like ready meals which are based on an average 2000 calories for women. Well that's fine except half of women are below average by definition. They shouldn't be clearing their plates! Also see restaurants and customer expectations of portion size. (Ironically the posher you go, the smaller the portion on your plate). Add to that how ready meals are actively designed to be moreish to encourage more purchases. If you have a homemade meal of the same size compared to a ready meal of the same thing, one will leave you feeling like you one more because of food technology. Also see serving suggestions. They don't match what you'd consider normal consumption. Even recipes 'go large'.
Then there's the invention of the car. Parents don't walk their kids to school anymore. I get 5000 steps a day from popping my son to school. The woman two doors down puts her kids in the car and drives. I arrive before her. She has weight and health issues - but this is definitely partly a product of her reliance on the car and the need to park as close to the door as possible. You can see it in the supermarket car park. Those people who drive around to get the spot closest to the door and usually not stick thin. It's an attitude. Could I walk to the shops 10 mins away or is it easier to jump in the car? Repeat a 100 times. Or how easy is it to get a packet of crisps? Put the Crisps upstairs and see if that changes how often you can be bothered to get them.
Which brings me to having snacks in the house full stop. Eating between meals is a new concept. It's a marketing invention. We don't need food as a reward.
Then compare all of thisbhow historically we laboured in the fields and that would burn thousands of calories more than we do now. And we had periods of lack of food where you would go hungry and your body was designed to compensate this over the course of a year with how it stored calories. Genetically that hasn't changed but culturally we have. We need to be conscious of it.
I think one of the biggest things here is the process of thinking about how we eat, not just putting what we are given in our mouths at a set time, which is what so many people do without a second thought because its easy.
The reality is that people who do not put on weight, don't necessarily work at keeping the weight off, they merely think better about how they don't put it on in the first place.
In terms of strategising for that you have to set people up for life from childhood. What is normalised at home really does make a difference here too because you have an inter generational problem now set in. And this makes it much more difficult to resolve. Often this is closely tied to cultural attitudes to food and celebration.
Its always interesting to reflect on how much people eat at Christmas in this context. The average person has 10000 calories on Christmas day. Then wonders why they've put on weight over Christmas. It's perfectly possible to have a good Christmas with all the food you like without going that far over board.
You just have to think about it and break the habits of convenience and automatic eating merely because you can. All these little things add up. Even tackling one can make a difference without 'going on a diet'. I think I'd like to see a TV show doing something on this better.