Pepsi Ingredients: A Taste that Kills 12 Minutes of Life

Last reviewed: October 2026. Reflects the current U.S. 12 fl oz Pepsi formula. Pepsi Zero Sugar, Diet Pepsi, and the Pepsi Prebiotic Cola launched in fall 2025 are compared below.

Pepsi has eight ingredients, and the only one that separates it from Coca-Cola on paper is a second sweetener: Pepsi lists both high fructose corn syrup and sugar. Everything else — the caramel color, the phosphoric acid, the caffeine, the “natural flavor” — is the same cast in a slightly different order, and the result is 41 g of sugar in a can, two more than Coke. Here’s all Pepsi ingredients, what it does, what the research says, and how the zero-sugar versions differ, because Pepsi’s two diet colas use completely different sweeteners.

Quick answer: what’s in Pepsi?

The full Pepsi ingredients list

Two things to notice. Sweetener appears twice — corn syrup at number two, sugar at number four — which is how Pepsi gets to 41 g; by weight there’s more sweetener than anything but water. And there’s no preservative: that much sugar in that much acid is already hostile to microbes, which is why the diet versions have to add potassium benzoate.

Pepsi ingredients explained

Carbonated water Fine

Filtered water with dissolved CO₂. The bubbles contribute a little carbonic acid; the phosphoric acid below is what sets the pH.

High fructose corn syrup Flagged

The primary sweetener. HFCS-55 is about 55% fructose and 45% glucose, nearly identical to table sugar’s 50/50 split, and your body treats the two almost the same way — head-to-head trials find no meaningful difference in blood sugar, insulin, or weight at equal doses. The problem isn’t that it’s corn syrup; it’s the dose. Daily sugar-sweetened soda is one of the most consistent dietary predictors of weight gain, type 2 diabetes, and fatty liver in large studies, and the association is strongest for liquid sugar because it doesn’t trigger fullness. Our high fructose corn syrup breakdown covers the research.

Caramel color Flagged

Cola brown. Pepsi uses Class IV caramel, made with ammonia and sulfite compounds, which produces the byproduct 4-MEI. California listed 4-MEI under Proposition 65 in 2011 after it caused tumors in mice at high doses, and both Pepsi and Coke reformulated in 2012 to stay under the warning threshold. Pepsi’s reformulation lagged Coke’s outside California for a while — a 2014 Consumer Reports test found Pepsi cans in New York well above the threshold — but current levels are low. Cosmetic ingredient, low concern. Our caramel color breakdown has the 4-MEI history.

Sugar Flagged

The second sweetener — cane or beet sucrose, listed separately from the corn syrup. Pepsi has used the blend since the 2000s; it’s why Pepsi tests slightly sweeter than Coke in blind tastings and why its sugar number is higher. Same metabolic story as HFCS. The two together are the 41 g.

Phosphoric acid Flagged

The cola bite, and the most direct harm in the can: pH around 2.5, enough to soften enamel, with the damage tracking how long you sip. Observational studies link daily cola — specifically cola, which points at phosphoric acid — to slightly lower bone density in women and higher kidney-disease risk at two-plus cans a day. In every Pepsi, regular or diet. Our phosphoric acid breakdown covers the research.

Caffeine 38 mg

38 mg per 12 oz — a little more than Coke’s 34, about a third of a cup of coffee, and well under the FDA’s 400 mg daily guidance. Caffeine-Free Pepsi exists.

Citric acid Fine

The ingredient Coke doesn’t have. It adds a sharper, more citrus edge and is the main reason Pepsi and Coke taste different despite near-identical labels. Same molecule as in lemons; it adds a little to the enamel issue and nothing else.

Natural flavor Undisclosed

The proprietary cola blend — generally believed, like Coke’s, to involve citrus oils, vanilla, and spices. “Natural” means plant- or animal-derived, not simple or disclosed.

Pepsi nutrition facts

The caffeine column has the surprise: Pepsi Zero Sugar has 69 mg, nearly double regular Pepsi and double Coke Zero. Prebiotic Cola figures are from PepsiCo’s launch materials and may vary by flavor.

Pepsi vs. Coke: is one healthier?

No, in any way that matters. Pepsi has 2 g more sugar and 4 mg more caffeine; Coke has 15 mg more sodium. Both have caramel color and phosphoric acid; neither has preservatives, dyes, or artificial sweeteners. The real difference is citric acid, which is why Pepsi reads as sweeter and sharper and Coke as rounder. If you’re choosing between them on health grounds, you’re choosing between 39 and 41 g of sugar, and the answer is to choose how often rather than which. The one honest edge: Pepsi’s sugar is partly cane sugar, which some people prefer for taste — and which, as the cane sugar Coke launch showed, makes no nutritional difference.

Pepsi Zero Sugar, Diet Pepsi, and Prebiotic Cola

Pepsi is unusual in selling two zero-sugar colas with different sweeteners, which matters if you’re avoiding one in particular.

• Pepsi Zero Sugar uses aspartame plus acesulfame potassium (reformulated in 2023 to taste closer to regular Pepsi) and carries 69 mg of caffeine — the highest of any mainstream cola. It has the phenylalanine warning.
• Diet Pepsi has been aspartame-free since 2020, using sucralose plus Ace-K. 35 mg caffeine. It’s the choice for people avoiding aspartame specifically; sucralose has its own research questions.
• Pepsi Prebiotic Cola, launched in fall 2025 after PepsiCo bought Poppi, has 5 g of cane sugar, stevia, and 3 g of prebiotic fiber in a 12 oz can. Far less sugar than regular Pepsi; the “prebiotic” claim rests on a fiber dose below what the gut-health research typically uses. Our Poppi breakdown covers the same question in detail.

Is Pepsi bad for you?

The concerns, ranked by evidence:

1. Sugar. 41 g is above the AHA’s daily added-sugar limit for both women (25 g) and men (36 g) in a single can.
2. Phosphoric acid and teeth. The clearest direct harm; sipping makes it worse. Drink with food, rinse after, wait before brushing.
3. Bones and kidneys. Associations at two-plus colas a day; not proven causal, consistent enough to take seriously at that intake.
4. Caramel color. 4-MEI is real, reduced since 2012, low per can.
5. Caffeine. 38 mg is minor for adults; matters for kids, and jumps to 69 mg in Zero Sugar.

Pepsi for keto, diabetes, and kids

Keto: no — 41 g of carbs. Pepsi Zero Sugar or Diet Pepsi are zero-carb.

Diabetes: fast liquid sugar with nothing to slow it; close to the worst-case drink for glucose control, and why half a can is a standard hypoglycemia treatment.

Kids: the AAP’s limit is under 25 g of added sugar a day; one can is 41. Caffeine adds a second reason.

Cleaner alternatives

Same list as for Coke: Zevia Cola (stevia, no caramel color) or Olipop Vintage Cola (stevia, 2 g sugar, real fiber) if you want cola without artificial sweeteners and without the sugar; Pepsi Prebiotic Cola is PepsiCo’s own answer in that category. If you want Pepsi, have a Pepsi, with a meal, not every day.

This article is for informational purposes and is not medical advice. Talk to a doctor or registered dietitian about your individual nutrition needs.