Long ago, these foods would have mainly been fruit

Stuart’s observations explain these mysteries. All four observations (liking for sweetness, separation of main course and dessert, sweet things taste bad when hungry, dessert after dinner but not lunch) make sense if we have evolved mechanisms to push us to eat sweet foods near bedtime. Because sleep is so important for health, there would be powerful selection for anything that improved sleep.

Basic physiology

4. The brain runs on glucose. In my brain tests, sugar drinks, cupcakes, and other sugar-rich foods make an obvious difference 30 minutes to 2 hours later. (I get faster.) And the brain controls sleep, an enormously complicated and time-sensitive process. Too little blood sugar during sleep could easily disrupt sleep.

5. Basic nutrition. Honey is half glucose, half fructose. When you eat it, the glucose enters the blood quickly and would supply glucose to the brain in the first half of the night. In contrast, the fructose turns into glucose and enters the blood slowly (fructose has a low glycemic index). This would supply glucose to the brain in the second half of the night. Many fruits, such as bananas, figs, and grapes, have a similar composition (similar amounts of fructose and glucose). Most fruits have plenty of fructose and glucose. A glucose/fructose mixture makes honey near the start of sleep a good source of blood glucose over an extended period without food. Notice that you need both – glucose and fructose – in roughly equal amounts to get a roughly steady supply over six or seven hours.

6. Basic engineering. When you are asleep, there can be no “course correction”. You must subsist for the next six or so hours without any behavioral help, such as drinking water when thirsty. So it makes design sense to do something shortly before sleep that will provide a relatively steady supply of glucose throughout the night (“time-release”). That won’t be a lot of glucose at once. You need a food that is a mix of sugars.

Why https://hookupdate.net/it/mingle2-review/ is sugar consumption often correlated with poor health?

7. Support for general idea. A few weeks ago a woman told me that when she ate very low-carb her sleep suffered, so she ate more carbs and her sleep got better. This supports the general idea behind what Stuart found – that the brain needs a certain amount of glucose to work well during sleep and it is best if it gets at least some of it from carbohydrate.

8. Explanation of correlation of sugar and bad health. This is easy to explain: sugar at the wrong time is the problem. Too much sugar during the day interferes with the bedtime benefit (and may also interfere with sleep in general). Stuart found exactly this: Eating lots of sugary foods during the day disturbed his sleep and eliminated the honey effect (“if I eat a lot of sugar during the day . . . then I don’t feel refreshed [when I wake up] regardless of the honey”). Too much sugar during the day could make it harder to get optimal glucose levels during the night. For example, too much sugar during the day might raise insulin levels, causing too-low blood sugar at night and/or causing a fructose/glucose mixture eaten at bedtime to be digested too quickly. Anything that harms sleep will increase disease. Good health, good sleep and good immune function are closely connected. An example of the evidence is that shift workers get more cancer than non-shift workers.

9. Reichenbach’s Common Cause Principle, in my paraphrase, is lightning doesn’t strike twice in one place for different reasons. If two rare events might have the same cause, they probably do. In this case, lightning has struck three times in one place. 1. Huge sleep improvement from tiny dietary change. 2. Huge strength improvement from tiny dietary change far from time of exercise. 3. Evolutionary explanation of why sugars taste good, why dessert exists and follows the main course, and so on. Before this, no one has come close to a plausible evolutionary explanation. The absence of an explanation is remarkable because two of the phenomena – sweetness tastes good, sweets are eaten separately after the rest of the meal – are so obvious.