Does Pizza Have a Low Glycemic Index? I Fell For It And I'll Tell You What Happened

I’m going to tell you an embarrassing story before turning into technical content. I fell for a myth so well wrapped that I kept eating wrong for months even feeling in my body that something didn’t add up.

If you identify with this, relax: there’s good science explaining why. And more importantly — a way not to repeat it.

The Video That Got Me

I was scrolling the feed and up popped a fitness influencer (6 million followers, virtual lab coat, colorful graphs) saying:

“You think pizza is the villain? Surprise: the glycemic index of margherita pizza is LOWER than white rice, ripe bananas, and even most whole-grain breads. Whoever said pizza makes you fat lied to you.”

There was a table. There were numbers. There was “science.” And I, going through a bad insulin moment, with food issues, wanting to go back to eating “clean without paranoia,” bought the whole narrative.

I started allowing pizza more frequently. “It’s fine, it’s low GI, low impact, I can adjust my calories.” I trusted.

What Actually Happened to Me

Italian restaurant. Large margherita, thin crust, fresh pomodoro, buffalo mozzarella. It was supposed to be the “queen of healthy pizzas” according to the video. I ate with the calm of someone making an intelligent choice.

Result in the next 4 hours:

+30 min:  Apparent satiety, but with the urge for "one more slice"
+45 min:  Ate 2 more slices beyond what I'd planned
+1h:      Heavy stomach, strange tired feeling
+2h:      Total brain fog, couldn't reason
+3h:      Deep lethargy, wanted to lie down, no energy
+4h:      Woke from the "coma" hungry again (?!)

The part that pissed me off was this: I kept eating even feeling bad. As if an external force were pushing. I ate 6 slices when I’d planned 3.

I didn’t have a “lack of discipline.” I had been tricked by a wrong metric and my brain was responding exactly as it was programmed to respond.

I went to investigate. And what I found left me outraged.

The Trick: The Influencer Was Technically Right

Here the con gets refined: he didn’t lie. He just chose the metric that seemed favorable and ignored the other 4 that mattered more.

Metric 1: Glycemic Index (GI) — The One He Showed

The Glycemic Index measures how much 50g of carbohydrate from a food raises blood glucose in 2 hours, compared to pure glucose.

Pure glucose ............ 100 (reference)
White bread ............. 75
White rice .............. 73
Boiled potato ........... 78
Ripe banana ............. 62
MARGHERITA PIZZA ........ 60 ← "Look at that!"
Al dente pasta .......... 50

Really — by isolated GI, margherita pizza appears more “calm” than rice and bread. The scientific explanation is even pretty:

The fat in the cheese slows gastric emptying
The dough fermentation creates slightly more resistant starch
The fiber in the tomato sauce helps
The protein in the cheese modulates carb absorption

All of this is true. That’s why the metric favors pizza.

But GI is the wrong metric for evaluating a real meal.

Metric 2: Glycemic Load (GL) — The One He Hid

GI is per 50g of carb. But you don’t eat 50g of carb, you eat the whole plate.

The Glycemic Load (GL) corrects this. It’s the formula:

GL = (GI × grams of actual carbohydrate) / 100

Compare:

50g of cooked rice (small portion):
GI 73 × 14g of carb / 100 = GL 10 (LOW)

Whole large margherita pizza (8 slices):
GI 60 × 180g of carb / 100 = GL 108 (EXTREME)

Same “low GI” pizza has a glycemic load 10x higher than a decent portion of rice.

In practical terms: you threw 180g of carbohydrate into your organism in one meal. The fact that the GI is 60 instead of 73 is irrelevant when the volume is massive. It’s like saying “this candy is less sweet” while eating the whole bag.

Metric 3: Insulin Index (II) — The One He Doesn’t Know

In 1997, researcher Susanne Holt at the University of Sydney published a study that shook nutrition (and is still largely ignored today): the Insulin Index.

The idea: what if we measured the response of insulin instead of glucose? Would they be the same?

Result: many foods have an insulin response much greater than the GI suggests. Mainly:

FOODS WITH INSULIN INDEX > GI:
- Dairy (milk, yogurt, cheese)
- Lean meats
- Combinations of starch + dairy + protein
- White bread with butter > white bread alone

And do you know which combination has a DISPROPORTIONATELY high insulin index? Guess.

Wheat dough + melted cheese + animal protein.

That is: pizza.

Pizza can have moderate GI, but II is high because:

The amino acids in the cheese (leucine, isoleucine, valine) stimulate insulin directly
The combination starch + protein + fat triggers incretins (GLP-1, GIP)
Incretins amplify the insulin response by 50-70%

In modern studies with continuous glucose monitor (CGM) + insulin dosage, pizza gives an insulin response sustained for 4-6 hours — even when the glucose peak looks well-behaved.

Glycemia looks calm on the device. Insulin is sky-high. You just feel the effect.

That lethargy that you (and I) felt? That’s exactly it. High insulin pulls nutrients into cells, drops glucose available to the brain, activates orexin-suppression, and you become a zombie.

Metric 4: Bliss Point and Hyperphagia — The One No One Talks About

And to close, there’s the neurological aspect that no GI influencer mentions.

Howard Moskowitz, psychophysicist at Harvard, was hired by the ultra-processed industry in the 80s to find what he called the “bliss point”: the exact combination of salt + fat + sugar (or starch) that makes the brain turn off satiety.

The bliss point recipe is a specific multisensory combination that activates the reward system (dopamine) more strongly than satiety (leptin, CCK). Result:

FOODS WITH BLISS POINT ACTIVATED:
- Pizza (salt + fat + starch + cheese umami)
- Burger with cheese
- Ice cream (fat + sugar + cold)
- French fries
- Bag chips

NEUROLOGICAL EFFECT:
- Dopamine rises
- Brain asks for MORE, not less
- Satiety stays suppressed
- You eat beyond physiological need

I didn’t eat 6 slices because I’m weak. I ate 6 slices because pizza is precise food engineering to make me eat more than I need. It’s industrial design, not lack of willpower.

The Final Damage Bill

Combining the 4 metrics, here’s what really happened when I ate that “healthy pizza”:

REAL DAMAGE OF A LARGE MARGHERITA PIZZA:

GI of pizza ............... 60 (medium, "ok")
GL total .................. ~108 (EXTREME)
Insulin Index ............. ~80 (high)
Calories .................. ~1800-2200
Sustained insulin ......... 4-6h elevated
Hyperphagia activated ..... Yes → ate 2 extra slices
Post-meal brain fog ....... 3-4h
Rebound hunger ............ 4h later (insulin still high)

Conclusion: catastrophic. But the influencer said "low GI."

What I Learned (So You Don’t Fall)

This episode changed how I read any nutritional claim. Today I apply 5 questions before accepting any “fitness truth” from the internet:

1. What specific metric is he citing?

If it’s just one (GI, “low carb,” “high in protein,” etc.), be suspicious. Real food is multidimensional.

2. What actual portion am I going to consume?

GI of 50g is different from glycemic load of 200g. Always convert to GL in the context of YOUR meal.

3. What’s the insulin response, not just glucose?

Dairy, lean meats, and macro combinations have a high insulin index independent of GI. For someone with insulin issues, II > GI.

4. Is this food bliss point engineering?

If it was designed to make you eat more (pizza, fast food, ice cream, ultra-processed), the amount you think you’ll eat is NOT the amount you’ll eat. Treat as exception, not as routine.

5. What’s the insulin AUC over the next 6 hours?

This is the most important metric and almost no one measures it. It’s the central concept I covered in Fasting, Autophagy and Insulin: Why the Big Meal Cancels the Benefits — if you haven’t read it yet and have insulin issues, it’s required reading.

What I Do Today

I didn’t cut pizza out of my life. I ate it the week before last — the difference is that now I know what I’m doing:

HOW I EAT PIZZA TODAY:

1. Reserve it for specific occasions (not weekly routine)
2. Eat 3-4 slices, not 6-8 (knowing the bliss point)
3. Pair with a giant salad before (satiety + fiber)
4. Don't combo with soda (insulin index doubled)
5. Don't eat fasting (amplified insulin response)
6. Walk 30 min after (muscle pulls glucose without insulin)
7. Next meal: 5-6h later, light and protein-rich

Result: zero brain fog, zero lethargy, zero rebound hunger. Same pizza. Different strategy.

The Most Important Lesson

The influencer didn’t lie to me. He spoke an isolated truth and let me build the wrong conclusion myself. This is the most sophisticated con of the information era:

The half-truth is more dangerous than the whole lie. Because you can defend it with “sources.”

Pizza GI is 60. That’s a fact. The isolated fact is useless — worse, it’s harmful. You need the whole context: GL, II, volume, neuroscience, your metabolic condition, your day, your training, your bedtime.

If you’re reading this and identified, you’re not weak and you weren’t stupid. You were a perfect target for food marketing disguised as science. The difference between those who repeat the mistake and those who learn is understanding the game.

And the game is this: a single metric never tells the full story of what’s happening in your body.

To go deeper into the metabolic mechanism that explains the “post-pizza brain fog”:

→ Fasting, Autophagy and Insulin: Why the Big Meal Cancels the Benefits — where I explain the metric of 24h insulin AUC that no one tells you about, and why it’s what really counts.

References:

Holt SH, Miller JC, Petocz P. “An insulin index of foods: the insulin demand generated by 1000-kJ portions of common foods.” American Journal of Clinical Nutrition. 1997;66(5):1264-1276.
Bao J, et al. “Food insulin index: physiologic basis for predicting insulin demand evoked by composite meals.” American Journal of Clinical Nutrition. 2009;90(4):986-992.
Atkinson FS, Foster-Powell K, Brand-Miller JC. “International tables of glycemic index and glycemic load values: 2008.” Diabetes Care. 2008;31(12):2281-2283.
Moss M. Salt Sugar Fat: How the Food Giants Hooked Us. Random House. 2013.
Hall KD, et al. “Ultra-Processed Diets Cause Excess Calorie Intake and Weight Gain.” Cell Metabolism. 2019;30(1):67-77.
Holst JJ. “The physiology of glucagon-like peptide 1.” Physiological Reviews. 2007;87(4):1409-1439.