Real CGM data from 1,381 members

Does pizza spike your blood sugar?

We looked at Vively members who ate pizza on its own while wearing a glucose sensor. Here is what happened, how it compares, and how to find out what it does to you.

A slice of margherita pizza
+1.6mmol/L
typical rise after pizza on its own
01234 mmol/L

Half of members rose between 0.8 and 2.6 mmol/L.

Peak at about 45 minStill raised at 2 hours

Short answer: Pizza raised blood sugar by a typical 1.6 mmol/L in 1,381 Vively members who wore a continuous glucose monitor (CGM) and logged it on its own. The middle half of members rose between 0.8 and 2.6 mmol/L. The peak was modest, but pizza kept members' glucose raised for longer than almost anything else we looked at.

The basics

Why a glucose spike matters

When you eat carbohydrate, your body breaks it down into glucose and your blood glucose rises. That is normal, because glucose is your body’s main fuel. Insulin then moves it out of your blood and into your cells, and your level comes back down.

You eatUsual levelPeak The risepeak minus yourusual level Back to baseline
How to read a glucose curve (illustration). The rise is the number we show for every food.

How you feel a few hours later

A big rise is sometimes followed by a dip below where you started. In a study of 1,070 people, those with bigger dips after breakfast felt hungrier sooner and ate more over the rest of the day.

How hard your insulin works

Bigger, more frequent rises mean your body releases more insulin. If your cells stop responding well to it (insulin resistance), your body has to make even more. Insulin resistance usually builds for 10 to 15 years before a standard glucose blood test picks it up.

Your long-term health

Studies of people without diabetes have linked higher glucose levels, including two hours after a sugary drink, with a higher risk of heart disease. Higher rises after meals are also often one of the first changes on the way to type 2 diabetes.

One rise is not a problem

Glucose is meant to go up after you eat. What matters is your pattern over weeks: how high you go, how often, and how quickly you come back down. That pattern is personal, so measuring it beats guessing.

If you have diabetes or take medicine that lowers glucose, talk to your doctor before changing how you eat.

Head to head

Pizza vs pasta

Two groups of members in the Sydney and Melbourne time zones, each eating one food on its own: 733 for pizza and 565 for pasta. These are their average curves. Drag across a chart to read it.

A slice of margherita pizza

Pizza

733 members
A bowl of spaghetti with tomato sauce

Pasta

565 members
33%

lower average peak for pasta

33%

less glucose under the curve for pasta

1.6 vs 1.3

typical rise in mmol/L, pizza vs pasta

Average curves look gentler than any one person’s, because people peak at different times. These are different groups of people, so treat it as a guide, not a verdict.

31% barely moved. After pizza on its own, 31% of members rose less than 1 mmol/L and 25% rose 2.5 or more. Which group are you in?

Test it on yourself
Everyone is different

Ten people, ten different results

Line up 1,381 members from smallest to biggest typical rise after pizza, then pick ten people evenly spaced along the line. Same food, very different curves.

+0.2
Person 1
+0.2
Person 2
+0.8
Person 3
+1.2
Person 4
+1.5
Person 5
+1.8
Person 6
+2.1
Person 7
+2.6
Person 8
+3.1
Person 9
+4.3
Person 10
31%

barely moved, with a typical rise under 1.0 mmol/L

25%

rose 2.5 mmol/L or more

Why pizza raises your glucose

Pizza combines a white flour base with a lot of cheese and often fatty meats. The fat slows digestion, so the rise starts later and lasts longer. Members' curves peaked around 45 minutes after eating and were still well above baseline nearly three hours later.

That long, slow tail is why pizza can look fine at the one-hour mark and still keep your glucose up for the evening.

Portion size, what you ate earlier, sleep, stress, movement and your menstrual cycle all change the curve too. That is why we built Vively around testing your own meals instead of handing out food lists.

Play

Guess the spike

Five quick rounds using our members’ data. How well do you know your pizza?

How it compares

Where pizza sits among 20 everyday foods

Typical rise in mmol/L when each food was eaten on its own. Every food has at least 30 members behind it. Tap a food to see its page.

See all 38 foods on our glucose spikes page.

Your turn

Three pizza experiments to run on yourself

Averages only get you so far. These are the tests our members run with their sensors.

Members’ result

Pizza vs pasta

Swap one for the other at the same meal on different days. In our members, the typical rise was 1.6 mmol/L for pizza and 1.3 for pasta.

Try it

Thin vs thick crust

Thin crust means less base. Add a side salad, stop at two or three slices, and compare.

Try it

Sit vs walk

After the same meal, sit one day and take a 10-minute walk the next. Compare how high you go.

Your pizza curve is yours alone

Wear a CGM with Vively and see the rise, the peak and the recovery for every meal you log. Then try a swap and compare the two curves side by side.

Get your CGM
Vively app meal screen showing a glucose curve next to a swap from the week before

Questions about pizza and blood sugar

Does pizza spike blood sugar?

It raises it for longer more than it spikes it. 1,381 Vively members wearing a CGM rose a typical 1.6 mmol/L after pizza, which is moderate, but their glucose stayed raised for nearly three hours. The middle half rose between 0.8 and 2.6 mmol/L.

Why does pizza keep blood sugar high for so long?

Pizza has a lot of fat from cheese and toppings, which slows how quickly your stomach empties. The carbohydrate from the base arrives gradually, so the curve is lower but longer.

Is thin crust pizza better for blood sugar?

It has less base, so less carbohydrate per slice, and would be expected to raise glucose less. Our members don't log crust type reliably, so this is a good one to test yourself.

What is a normal rise after eating?

There is no official cut-off for a spike in people without diabetes. In a 2019 study of healthy adults who wore CGMs, glucose stayed between 3.9 and 7.8 mmol/L for about 96% of the day. Rises after meals are normal. How high you go, how long you stay there and your pattern over weeks matter more.

How did you get these numbers?

We used meals logged in the Vively app by members wearing a CGM between January 2022 and October 2026, leaving out members who told us they have type 2 diabetes, and our own staff. The rise is the highest reading in the two hours after eating, minus the member’s average for the four hours before. If glucose fell, we counted the rise as zero. We took each member’s own median first, then the median across members. “On its own” means the food was the only item logged for that meal. The curves use members in the Sydney and Melbourne time zones, meals since January 2023 and each member’s three most recent meals of each kind. Data is de-identified and only shown when at least 30 members contribute. This is observational app data, not a controlled GI test, and portions vary.

More from Vively

Sources

  1. Vively member CGM data, de-identified and aggregated, pulled 12 and 13 October 2026.
  2. Shah VN et al. Continuous glucose monitoring profiles in healthy nondiabetic participants: a multicenter prospective study. Journal of Clinical Endocrinology and Metabolism, 2019.
  3. Wyatt P et al. Postprandial glycaemic dips predict appetite and energy intake in healthy individuals. Nature Metabolism, 2021.
  4. Levitan EB et al. Is nondiabetic hyperglycemia a risk factor for cardiovascular disease? A meta-analysis of prospective studies. Archives of Internal Medicine, 2004.
  5. Ceriello A et al. Guideline for management of postmeal glucose. Nutrition, Metabolism and Cardiovascular Diseases, 2008.

This is observational data from real meals, not medical advice.