# Diabetes logbook: log carbs and insulin next to your Libre

> Dulce's Logbook lets you record carbs, insulin (bolus or basal, kept apart) and fingerstick glucose in seconds, from the Logbook tab or the Carbs and Insulin buttons on the home screen. Every entry sits on the same timeline as your sensor readings, so a spike has its reason right next to it. The Logbook is free; Dulce Pro is only needed to read data from Apple Health.

URL: https://dulceglucosa.com/en/blog/diabetes-logbook-carbs-and-insulin  
Author: Giorgi Khimshiashvili  
Published: 2026-10-19  
Updated: 2026-10-22

Your sensor measures glucose by itself, but it doesn't know what you ate or how much insulin you took. Without that, a mid-afternoon spike is just a line going up. Logging is what turns the chart into something you can understand, which is why it has to be quick: if it's a chore, it doesn't happen.

![Dulce Logbook with insulin and carb entries and the add-entry sheet set to 5.5 units of insulin](https://dulceglucosa.com/guides/logbook.jpg)

*The Dulce Logbook and the add-entry sheet.*

## What you can log

From the **Logbook** tab, or with the **Carbs** and **Insulin** buttons on the home screen, you can add:

- **Carbs**, in grams, with an optional note on what you ate.
- **Insulin**, in units, marked as bolus or basal.
- **Exercise**, in minutes.
- **Manual glucose**, for example a fingerstick reading to check your sensor.
- A free-text **Note**.

## Log it in seconds

1. **Tap + or a quick button**: In the Logbook tap **+**, or use Carbs or Insulin on the home screen.

2. **Pick the amount**: Slide the ruler to the amount or tap one of the shortcuts to add to it.

3. **Say when**: Now, 15 minutes ago, 30, 1 hour ago or another time. So it doesn't matter if you log it late.

4. **Save**: Tap **Save**. The entry shows up instantly in your Logbook and as a marker on the chart.

Made a mistake? Tap any entry to edit or delete it.

[Start your logbook in Dulce](https://apps.apple.com/app/apple-store/id6770694596?pt=127601978&ct=blog_logbook&mt=8)

## Everything on one timeline

The Logbook puts what you log and your sensor readings in order, day by day, with the period's time in range, average and GMI at the top. You can look at today or the last 7, 14 or 30 days.

If you use other apps that save insulin or carbs to Apple Health (a smart pen or a food app, for example), Dulce can read them and show them here too, marked with where they came from. See the [Apple Health guide](https://dulceglucosa.com/en/blog/freestyle-libre-and-apple-health).

## What it's good for in practice

- **Understanding a spike.** Did you go up after lunch because the bolus was late, or because there were more carbs than you counted?
- **Bringing data to appointments.** Your care team understands a week with meals and insulin far better than a curve with no context.
- **Spotting patterns.** Together with the time-of-day view in the [Trends tab](https://dulceglucosa.com/en/blog/glucose-trends-time-in-range-gmi), it's easy to see which meal or time keeps repeating.

> Dulce is a logbook, not a dose calculator: it doesn't recommend how much insulin to take. That decision is yours and your care team's.

## FAQ

**Do I need Dulce Pro for the Logbook?**

No. The Logbook and the Trends tab are in the free version. You only need Pro to read data from Apple Health.

**Can I keep bolus and basal apart?**

Yes. When you log insulin you choose bolus or basal, and it shows that way in the Logbook.

**What if I use mmol/L?**

Manual glucose is entered in whichever unit you chose in Settings, mg/dL or mmol/L.