How your stomach level works
Your stomach level is Surplus’s estimate of how full you’re likely to feel right now, and when you’ll have room for your next full meal. It’s worked out from what you’ve logged. It isn’t a measurement of your body, and it’s not medical advice.
What goes into it
- What you ate, compared with a meal for you. Surplus splits your daily calorie target across the day’s meals. A meal that size counts as one meal’s worth. A bigger plate counts for more, a snack for less. So the same food fills the bar more for someone with a smaller target.
- Meals add up. Everything you’ve eaten recently adds to the level, and each item fades on its own. A snack after lunch adds a little to what’s already there. It never makes room come sooner.
- Fat holds you a little longer. When a food’s fat is known, a fattier meal fades a bit more slowly.
- Drinks fade a little faster. A shake from your quick snacks, or anything you add to the Shake meal yourself, settles a little sooner than a plate with the same calories.
- It fades quickly at first, then slowly. The feeling of fullness eases most in the first hour or so after eating, so the bar moves soonest then.
When there’s room
Surplus says you should have room for a full meal once the level has come down far enough. It never says this sooner than an hour and a half after you last ate, and never later than three and a half hours (four and a half on I digest slower). Your reminders use the same time, so Surplus won’t nudge you to eat before there’s room.
When you’re too full for a plate but not for something drinkable, the page tells you a shake will still go down.
The graph
The graph starts at 6am, or an hour before your first meal once you’ve had it, and shows about four hours ahead: four hours past now, or past the time you should have space to eat. It grows through the day until it shows the whole day, up to midnight. The solid line is how your level has gone so far. The dashed line is where it’s heading if you eat nothing more. The shaded part marked “Space to eat”, from the time printed on the bottom edge, is when you should have space for a full meal: the line is down near Empty by then. Anything you eat moves it. Before you’ve eaten, it’s a flat line.
Why it runs a little ahead of you
Surplus is built for people who find it hard to eat enough. If you’ve been eating too little for a while, it’s common to feel full sooner and for longer. A model that matched that exactly would tell you to eat less often, which is the opposite of what you’re working towards. So the level is set to say there’s room a little before you might feel it yourself, to help you build the habit of eating more often.
Before your first meal
The day starts at 4am. Until you’ve eaten, the level says Ready, not Hungry. Many people aren’t hungry in the morning, and that’s normal. Eating your first meal anyway is what builds a morning appetite.
Changing how quickly it goes down
On the Stomach page, Digestion has two settings:
- Normal suits most people. Start here, and give it a week or two.
- I digest slower: if you still struggle to eat when Surplus says there’s room. Room comes later, by about 50 minutes for an ordinary meal: one that gave you room after about two and a half hours gives it after about three hours twenty.
Room still comes no sooner than an hour and a half after you last ate, and no later than three and a half hours on Normal or four and a half on I digest slower.