Ultra-Processed Foods and Blood Sugar: What the Research Shows
You can eat "healthy" and still spike your blood sugar all day.
That's not a scare tactic — it's what the research keeps finding.
Granola bars. Whole-grain cereal. Flavored yogurt. Protein shakes. These foods sit in the "healthy" section of the grocery store, but they share something with soda and fast food: they're ultra-processed. And that processing — not just the sugar — is what's quietly driving glucose problems for millions of people.
Multiple large-scale studies now link ultra-processed food consumption to poorer blood sugar control, a higher risk of prediabetes, and increased rates of type 2 diabetes — even when researchers controlled for calories, exercise, and overall diet quality.
In other words: it's not just about the sugar. Something else is happening.
In this article, we'll break down exactly what ultra-processed foods do to blood sugar, what the latest research shows, and the practical steps you can take starting today.
Let's dive in.
What Makes a Food "Ultra-Processed"?
The term was coined by Brazilian researcher Dr. Carlos Monteiro, who developed the NOVA classification system — a framework that categorizes foods not by their nutrients, but by the degree of industrial processing they've undergone.
The four NOVA groups, from least to most processed:
- Group 1 — Unprocessed or Minimally Processed: Whole foods as close to their natural state as possible. Eggs, fresh vegetables, plain meat, fruit, dried legumes, nuts.
- Group 2 — Processed Culinary Ingredients: Substances extracted from Group 1 foods and used in cooking: olive oil, butter, salt, sugar, flour. Rarely eaten on their own.
- Group 3 — Processed Foods: Whole foods with added salt, sugar, or fat to extend shelf life. Canned fish, some cheeses, freshly baked artisan bread.
- Group 4 — Ultra-Processed Foods (UPF): Industrial formulations with five or more ingredients, including additives you'd never find in a home kitchen: emulsifiers, artificial sweeteners, colors, flavor enhancers, modified starches, high-fructose corn syrup, hydrogenated oils.
Ultra-processed foods make up more than half of all calories consumed by Americans. A 2023 study in Nature Communications estimated that roughly 70% of the U.S. food supply is ultra-processed — meaning the average grocery cart is dominated by Group 4 foods.
And the most surprising part? Many of them are marketed as "healthy."
Packaged protein bars, whole-grain breakfast cereals, flavored yogurt, veggie chips, instant oatmeal packets, diet sodas — all Group 4.
What the Research Actually Shows
Ultra-Processed Foods Are Linked to Higher Blood Sugar — Even in Healthy People
In 2024, researchers at the University of Texas at Austin published findings from the TX STRIDE clinical trial, studying blood sugar control in adults with type 2 diabetes.
The result was clear: the more ultra-processed food someone ate by weight, the worse their blood sugar control was. And the more whole or minimally processed food they ate, the better their HbA1c — the standard 3-month average blood sugar measurement.
Critically, the effect wasn't simply explained by the presence of sugar or salt. The researchers found that food additives — the emulsifiers, artificial colors, flavor enhancers, and preservatives that make UPFs shelf-stable and hyperpalatable — were independently tied to worse outcomes.
Study Spotlight:
A 2024 analysis from the Atherosclerosis Risk in Communities (ARIC) study tracked over 13,000 American adults and found that higher UPF intake was consistently associated with higher diabetes risk across nine subgroups of ultra-processed foods — from sugary beverages to baked goods to UPF meats.
The Risk Starts Earlier Than You'd Think
Most blood sugar research has focused on middle-aged and older adults. But a 2025 study from the University of Southern California followed 85 young adults (ages 17–22) over four years.
The findings: increases in ultra-processed food consumption were tied to elevated blood sugar and early markers of prediabetes — even in this young, otherwise healthy group.
This matters because prediabetes rarely causes obvious symptoms. It silently accelerates insulin resistance — the underlying mechanism that drives type 2 diabetes — and most people don't know they have it until significant damage has already occurred.
Study Spotlight:
A 2024 study in The Lancet Diabetes & Endocrinology found that replacing ultra-processed foods with less-processed alternatives meaningfully reduced type 2 diabetes risk — confirming the relationship runs both ways. Eating fewer UPFs actually lowers risk.
Why Ultra-Processed Foods Wreck Blood Sugar
The glucose-spiking effects of UPFs aren't a mystery. Several mechanisms are now well-documented.
1. Destroyed Food Structure = Faster Glucose Absorption
When grains are refined and extruded — as in instant oatmeal packets, mass-produced bread, puffed cereals, or crackers — the physical structure of the original food is broken down. The bran layer that surrounds whole grains is removed. The fiber that slows glucose absorption is destroyed.
What's left digests almost immediately, sending glucose flooding into the bloodstream.
This is why a bowl of instant oatmeal can spike blood sugar nearly as fast as table sugar, even though it's "oatmeal."
Key Insight:
Whole oats and instant oats contain the same basic ingredients. But whole oats maintain their fiber matrix, slowing digestion and producing a gradual glucose response. Instant oats — steamed, rolled flat, and pre-cooked — lose that structure entirely.
2. Fiber Is Largely Absent
Dietary fiber is one of the most effective blood sugar regulators that exists. It slows glucose absorption, feeds beneficial gut bacteria that support insulin sensitivity, and promotes the kind of fullness that prevents overconsumption.
Ultra-processed foods are notoriously low in fiber. Eating a diet heavy in UPFs almost inevitably means a diet low in fiber — and that gap has direct consequences for glucose control.
3. Additives May Disrupt the Gut Microbiome
Several common food additives — including emulsifiers like polysorbate 80 and carboxymethylcellulose, artificial sweeteners, and certain preservatives — appear to alter the gut microbiome in ways that may impair insulin signaling and glucose metabolism.
The gut microbiome plays a larger role in metabolic health than most people realize. Disrupting its composition, even subtly and repeatedly, can affect how efficiently cells respond to insulin.
4. These Foods Are Engineered to Be Overeaten
In a landmark 2019 inpatient feeding trial, participants on an ultra-processed diet consumed an average of 500 more calories per day than those on an unprocessed diet — despite being matched for macronutrients on paper. They ate faster, felt full later, and stopped eating later.
When you combine foods that spike blood sugar rapidly with foods that are difficult to stop eating, you get a predictable outcome: chronic glucose volatility, insulin overwork, and eventual insulin resistance.
On "Diet" Foods:
Artificially sweetened beverages and reduced-fat UPF snacks are often assumed to be blood sugar–friendly. But research increasingly suggests that artificial sweeteners may still trigger insulin responses and microbiome changes — and that reduced-fat UPFs typically compensate with more sugar or modified starch to maintain palatability.
Still Seeing Spikes Despite Better Food Choices?
Diet changes help — but they're often not enough on their own.
Years of ultra-processed food can leave your glucose metabolism needing more support than food swaps alone can provide. That's why many people add a targeted blood sugar supplement to support the process — especially in the early stages of making dietary changes.
CinnaChroma by Barton Nutrition is a doctor-formulated supplement with six clinically studied ingredients designed to work together to support healthy glucose metabolism:
- 10:1 Cinnamon Bark Extract: Mimics insulin action and supports glucose uptake
- Chromium Picolinate: Enhances insulin sensitivity and carbohydrate metabolism
- Vanadium: Supports healthy insulin response
- Vitamin D3 & K2: Support glucose balance and inflammation response
- Selenium: Key antioxidant support for healthy metabolism
Formulated by Dr. Scott Saunders. 90-day money-back guarantee.*
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Practical Steps: What to Do With This Information
The goal isn't perfection — it's progress. Research consistently shows that even partial reductions in ultra-processed food intake produce meaningful improvements in blood sugar markers.
1. Read the Ingredient List (Not Just the Nutrition Label)
The nutrition facts panel won't tell you whether a food is ultra-processed. The ingredient list will. Watch for:
- Ingredients you wouldn't use at home: high-fructose corn syrup, modified food starch, hydrogenated oils
- Emulsifiers and stabilizers: polysorbate 80, carrageenan, lecithin in manufactured foods
- Artificial colors and flavors: Red 40, Yellow 5, "artificial flavor"
- Non-sugar sweeteners in packaged "diet" foods: acesulfame potassium, sucralose, aspartame
- The ingredient count itself: 15+ ingredients almost always means ultra-processed
2. Swap, Don't Eliminate
Research on dietary change consistently shows that swapping works better than restriction. Move one or two categories of UPFs toward less-processed alternatives:
- Instant oatmeal → rolled oats or steel-cut oats
- Flavored yogurt → plain full-fat yogurt with real fruit
- Packaged lunch meat → roasted or sliced whole cuts of meat
- Breakfast cereal → eggs (which stabilize blood sugar far more effectively)
- Soda and diet soda → sparkling water with citrus, or unsweetened iced tea
3. Prioritize Fiber at Every Meal
Because fiber is the primary mechanism by which whole foods slow glucose absorption, consciously adding fiber to each meal acts as a partial buffer — even if other food choices aren't perfect.
Legumes, non-starchy vegetables, avocado, nuts, and seeds are among the highest-fiber options that also have low glycemic impact.
4. Don't Overlook What You Drink
A 2025 study in Nature Medicine estimated that sugary drinks alone are associated with over 80,000 deaths from type 2 diabetes annually in the U.S., and link to roughly one in ten new type 2 diabetes cases.
Beverages often fly under the radar because people don't think of them as "food" — but liquid glucose hits the bloodstream extremely fast and produces pronounced spikes.
Final Thoughts
Ultra-processed foods affect blood sugar through multiple pathways at once: they destroy the food structure that slows glucose absorption, strip out the fiber that regulates it, and may disrupt the gut microbiome in ways that impair insulin sensitivity.
The research now includes tens of thousands of participants across multiple countries, using longitudinal follow-up and controlled feeding trials. The conclusion is consistent: the more ultra-processed foods make up your diet, the harder blood sugar control becomes — and the more you shift toward whole or minimally processed foods, the more your metabolic health tends to improve.
Here's your action plan:
- Read labels — the ingredient list tells you more than the nutrition facts
- Swap strategically — replace one or two high-impact UPFs at a time
- Add fiber — at every meal, every day
- Support your metabolism — give your body the nutrients it needs to do the work
When you do that, you don't just lower your blood sugar — you give yourself the energy, focus, and consistency to keep going.
Click here to learn more about CinnaChroma →
*These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
References
1. Hudson, E.A., et al. (2024). Degree of Food Processing is Associated with Glycemic Control in African American Adults with Type 2 Diabetes. Journal of the Academy of Nutrition and Dietetics. View study →
2. Li, Y., et al. (2025). Ultra-processed food intake is associated with altered glucose homeostasis in young adults. Nutrition & Metabolism, 22, 135. View study →
3. Stoltze Guldberg, L., et al. (2024). Ultra-processed food consumption and risk of diabetes: results from the ARIC study. Diabetologia. View study →
4. Dicken, S.J., et al. (2024). Food consumption by degree of food processing and risk of type 2 diabetes mellitus: results from the EPIC cohort. Lancet Regional Health Europe. View study →
5. Fang, Z., et al. (2025). Associations of sugary drinks with disease and death. Nature Medicine. View study →
6. Hall, K.D., et al. (2019). Ultra-processed diets cause excess calorie intake and weight gain. Cell Metabolism, 30(1), 67–77. View study →
7. Monteiro, C.A., et al. (2019). NOVA classification system. Public Health Nutrition. View study →
8. Martini, D., et al. (2023). Ultra-processed foods and the U.S. food supply. Nature Communications. View study →
