The sugar craving that hits you mid-morning did not start in the morning. It started with what you ate in your last hour.

This was the seventh issue this newsletter ever ran. It is worth another look, because the snack feels harmless and is not.

Eat something high on the glycemic scale late, a cookie, cereal, toast, and your blood sugar climbs fast. Sugar and refined starch reach the bloodstream almost at once.

Your body answers the spike with a large release of insulin. Insulin's job is to pull that glucose out of the blood and into your cells.

Here is the part that costs you. A big spike provokes a big insulin response, and the glucose can overshoot downward a few hours later.

So around 3am your blood sugar dips low. Not from fasting, but from the insulin you triggered at bedtime.

A glass of water by the bed is as ordinary as it gets. Scientists at the University of New Mexico looked at the water we drink every day.

They describe invisible shards that build up inside the brain and wear at the connections that keep memory sharp.

It is a strong claim, so hold it loosely. The researchers lay out what is behind it, and how to stop it.

>> See what the researchers found in everyday water

A low blood sugar reads as an emergency. The body releases adrenaline and cortisol to push the glucose back up.

Those are alerting hormones. They arrive in the deep middle of your night and pull you toward waking.

That is the 3am wake with the racing heart that nothing seems to explain. It was the snack, arriving on a delay.

The broken night and the glucose swing then set the next day's appetite. You wake under-rested and reaching for sugar, and the cycle restarts.

The anchor is the feeding research on the glycemic index, much of it from David Ludwig's lab. High-glycemic meals produce a sharp glucose rise, an outsized insulin response, and a later dip that can fall into the range that triggers those counter-regulatory hormones.

Lower-glycemic food, or the same carbohydrate paired with protein, fat, or fiber, flattens the whole curve. No spike, no overshoot, no 3am surge.

Here is the move, and the precision matters. The problem is not eating in the last hour, it is eating high-glycemic food in the last hour.

If you are hungry before bed, skip the sugar and the refined starch. Reach instead for something built on protein or fiber, a small bowl of plain yogurt, a boiled egg, a little cottage cheese.

Keep it small, enough to take the edge off hunger, not a meal. The goal is a flat overnight glucose line, not a full stomach. A late sweet snack spikes you at ten and wakes you at three.