We’re hearing a lot nowadays about how sugar is fattening – and so it is. Sugar plays a major role in serious obesity, but for most of us, it’s not the main or only reason we get fat.
What’s the reason then? The real reason many of us get fat is because of plain overeating. Almost all foods can make us fat when we overeat. That’s it in a nutshell so to speak. Overeating has become a massive problem and as a result obesity rates have tripled since 1980.
It’s not just sugar, but fats and grains also. Figure 1 shows how increasing calorie intake has matched our increasing weight.
So why do we overeat?
We overeat because so many different foods give us pleasure. When we’ve eaten to satiety with one kind of food we are easily tempted by appetising food of a different taste and texture, such as, bread, cake, biscuits, chocolate, meat, yoghurt, salted nuts, chips, soft drinks. Often we take in more than half as many calories again, even though we were full a few minutes ago.
Human Experiment
To prove this fact, a group of test subjects were housed for a week in a place where all their food came from a giant vending machine.
It was stocked with a great variety of foods, most of them calorie-dense and appetising to the eye – biscuits, cake, hamburgers, chocolate, muesli bars, chips, soft drinks, etc. All of them were free – a large selection of nice tasting foods to choose from for 7 days.
Result
Over the week these subjects over ate their normal calorie requirement, on average by more than 50% and gained an extra 2.2 kg in weight.
Mice Experiment
A similar week long experiment was carried out using mice. The mice were divided into 3 groups. One group ate regular rodent chow. The second group was fed human junk food, but only one type. The third group was fed human junk food, but in a variety of different types – like that available to the human volunteers in the former experiment.
Result
The weight increase of the mice is shown in figure 2. The mice eating the single type junk food, gained more weight than the mice on standard food – they were 6% heavier. However the mice that had a variety of junk foods to choose from, gained more than twice as much weight again and ended up 13% heavier than the control mice. In human terms about 9 kgs, in just one week.
Hunger is only one reason we eat
Suppose we are in a restaurant one evening and have eaten our main course to satiety and we feel comfortably full. Then out comes a tasty dessert and is placed before us on the table – something we really enjoy.
Will we eat it? Very likely yes, unless we have an iron will, perhaps doubling our calorie intake for the evening. What if a plate of boiled potatoes were brought out – would we eat that? Unlikely.
Studies have shown that when foods taste nice, have lots of calories and the variety is increased, on average we eat 44% more calories. The variety of foods available in our supermarkets has almost tripled since the 1980’s. We even eat an average 8% more calories on weekends than weekdays.
Another surprising research finding – the more people eating with us, the more we eat. Would you believe an incredible 70% more calories when eating with five people, than when eating alone? I have to admit all these findings ring true for myself, despite being a self-confessed health fanatic.
Cheap eat-out and take-away foods
Since the 1980’s, spending on high-sugar, high-fat, eat-out foods has increased 80%. Before 1980 around 90% of weekly food money was spent on food eaten at home. Now 50% of food money is spent away from home, mostly on a variety of fast, high calorie foods (USA figures).
Stress, boredom and habit-appetite
Stress and boredom can also increase our calorie intake, typically around 40%. Although under stress, a third of people eat less, or skip meals. However, stressed people do tend to choose calorie-dense comfort foods or alcohol.
Alcohol can result in poor food choices, as can lack of sleep – both may often lead to poor eating decisions.
Another cause of overeating is habit, habits are powerful. If it’s mealtime or snack time, most of us will eat, even when we’re not hungry, because that’s what we normally do at that time of the day.
How do they sell lots of high calorie food?
Make it nice tasting and addictive – ie, add fat, sugar, starch and flavour enhancers like glutamates (MSG)
Minimise fibre and protein (which trigger satiety, or a feeling of fullness)
Make it cheap
Make it convenient
Present it attractively
Make it seem healthy
Expose people to it
I’ll just exercise it off
Every time we eat extra calories, the fat (stored calories) can accumulate around our hips and belly for years. We tell ourselves we’ll exercise it off one day, but exercise is a painfully slow way to lose fat, and normally our appetite increases correspondingly to compensate (our brain is programmed to retain fat).
To burn off fat from a 70% increase in calories after just one binge meal, we’d have to walk for a solid three hours.