What Happens When You Consume Too Much Cornstarch?

November 4, 2025 •

4 min read

According to the USDA, one cup of commercial cornstarch contains 488 calories, primarily from carbohydrates, but lacks significant nutritional value. This absence of key nutrients is a major reason why consuming too much cornstarch, especially raw, can lead to numerous negative health consequences.

Quick Summary

Excessive cornstarch consumption, particularly in its raw form, is linked to health issues including rapid blood sugar spikes, increased risk of heart disease, and digestive problems. It also contributes to weight gain due to its high-calorie, low-nutrient profile. In some cases, a craving for cornstarch can signal the eating disorder pica, often associated with nutrient deficiencies.

Key Points

Blood Sugar Spikes: High consumption of cornstarch, a refined carbohydrate with a high glycemic index, can cause rapid and significant increases in blood sugar levels.
Digestive Issues: Raw cornstarch is difficult to digest and can lead to problems such as bloating, gas, stomach pain, and constipation due to its lack of fiber.
Lacks Nutrients: The processing of cornstarch removes most of the corn kernel's nutrients, resulting in a product that provides calories and carbohydrates but very little protein, fiber, or essential vitamins and minerals.
Weight Gain Risk: With nearly 500 calories per cup and a lack of satiating nutrients like fiber and protein, excessive cornstarch consumption can contribute to weight gain and obesity.
Linked to Pica: A persistent craving for cornstarch can be a symptom of pica, an eating disorder often linked to underlying nutritional deficiencies like iron or zinc.
Harm to Heart Health: Diets high in refined carbohydrates from sources like cornstarch are associated with an increased risk of heart disease due to factors like higher triglyceride levels.
Consider Alternatives: For thickening or gluten-free baking, healthier alternatives like oat flour, whole wheat flour, or almond flour offer more nutritional benefits and less risk of adverse health effects.

Nutritional Profile of Cornstarch

Cornstarch, a white powdery substance, is extracted from the endosperm of the corn kernel through a process called wet milling. This process strips away the kernel's valuable bran and germ, which contain most of its fiber, protein, vitamins, and minerals. What remains is a highly refined carbohydrate, consisting almost entirely of starch. While useful as a thickening agent in small quantities, its nutritional emptiness is a primary concern when consumed in large amounts.

The Dangers of Excess Carbohydrate Intake

Consuming a significant amount of cornstarch means flooding your body with a large dose of refined carbohydrates. Unlike whole grains, which contain fiber to slow digestion, cornstarch is broken down and absorbed very quickly.

Rapid blood sugar spikes: Cornstarch has a high glycemic index (GI), ranging from 77 to 88, meaning it can cause a rapid and significant increase in blood glucose levels. This rapid fluctuation is particularly dangerous for individuals with diabetes or insulin resistance but can affect anyone over time.
Increased risk of chronic diseases: A diet high in refined carbohydrates, like cornstarch, is associated with a greater risk of developing chronic health problems. These include heart disease, type 2 diabetes, and high blood pressure.
Heart health concerns: Regularly consuming a diet heavy in refined carbs can lead to higher levels of triglycerides, a type of fat in the blood. Elevated triglycerides increase the risk of heart disease.

Digestive System Complications

Eating too much cornstarch can wreak havoc on the digestive system. The lack of fiber is a major contributing factor, but it also depends on whether the cornstarch is cooked or raw.

Bloating, gas, and pain: When consumed raw, cornstarch is particularly difficult for the body to digest. The undigested starches can ferment in the gut, leading to excess gas, bloating, and stomach pain.
Constipation: Because cornstarch contains virtually no dietary fiber, it does not promote healthy bowel function. In some cases, consuming large amounts can lead to constipation, especially if water intake is insufficient.
Risk of foodborne illness: Raw cornstarch carries a small but present risk of carrying harmful bacteria. While heating and cooking typically eliminate this risk, raw consumption can potentially expose you to pathogens.

Potential for Weight Gain and Pica Disorder

Cornstarch is very calorie-dense but nutritionally sparse. One cup can contain nearly 500 calories, all from carbohydrates, with no balancing fiber or protein. This makes it a potential contributor to weight gain and obesity if consumed in excess without proper dietary management.

In some cases, a compulsive craving to eat cornstarch may be a sign of a more serious issue known as pica. Pica is an eating disorder characterized by cravings for non-food items, and a sub-type called amylophagia specifically involves the consumption of starches. Pica is often linked to underlying nutritional deficiencies, particularly iron-deficiency anemia or zinc deficiency. It is most common in children, pregnant women, and individuals with certain mental health conditions. If you or someone you know experiences persistent cravings for cornstarch, seeking medical advice is crucial for diagnosis and treatment.

Healthier Alternatives to Cornstarch

For individuals looking to thicken a dish or seeking a gluten-free alternative, healthier options are available that offer more nutritional benefits. These alternatives can provide a better balance of fiber, protein, and micronutrients.


Feature	Cornstarch	Whole Wheat Flour	Oat Flour	Almond Flour
Nutritional Value	Minimal; mostly refined carbs	Fiber, protein, vitamins	Fiber, protein, potassium	Protein, fat, magnesium
Fiber Content	Minimal	High	High	High
Protein Content	Minimal	Higher than cornstarch	High	High
Glycemic Index	High (77-88)	Medium	Low	Low
Best For	Thickeners in small amounts	Baking, general cooking	Gluten-free baking	Low-carb, gluten-free baking

How to Safely Use Cornstarch

For most people, using cornstarch in small quantities as a cooking ingredient is perfectly safe. For instance, a tablespoon or two to thicken a large pot of soup or sauce will not pose a health risk. The key is to avoid using it as a major component of your diet or consuming it raw in large quantities.

Mix cornstarch into a 'slurry' with cold water before adding it to a hot liquid to prevent clumping.
Always ensure cornstarch is thoroughly cooked, as heating helps break down the starch and improves its digestibility.
For those with diabetes, consult a healthcare provider or dietitian to discuss appropriate usage and potential alternatives.

Conclusion

While cornstarch is a common and safe ingredient when used sparingly, its overconsumption can lead to serious health problems. The refined, low-nutrient nature of cornstarch makes it a poor choice as a dietary staple. Excessive intake can cause rapid blood sugar fluctuations, increase the risk of heart disease, lead to weight gain, and cause digestive discomfort. Furthermore, a persistent craving for it can indicate an underlying medical condition like pica. By understanding the risks and opting for healthier, more nutrient-dense alternatives when possible, you can make smarter dietary choices and protect your long-term health. Moderation is key when it comes to this popular thickening agent, ensuring it remains a helpful cooking tool rather than a dietary hazard.

What to Do If You've Consumed Too Much Cornstarch

If you have accidentally consumed too much cornstarch, particularly if it was raw, it's essential to stay hydrated by drinking plenty of water. Monitor for any digestive symptoms like bloating, gas, or constipation. If cravings for non-food items persist, or if you experience concerning symptoms such as severe abdominal pain or allergic reactions, consult a healthcare professional immediately.

Mayo Clinic provides valuable information regarding celiac disease and gluten intolerance, highlighting the need for vigilance when selecting gluten-free products and emphasizing cornstarch's utility in such cases.

Frequently Asked Questions

Yes, it is not advisable to eat raw cornstarch in large quantities. Raw starch can cause digestive issues like bloating and gas and carries a slight risk of harmful bacteria. Cooking breaks down the starch, making it easier to digest.

Yes, excessive consumption of cornstarch can contribute to weight gain. It is a calorie-dense, refined carbohydrate with no fiber or protein, meaning it adds calories to your diet without providing a sense of fullness.

Cornstarch causes blood sugar spikes because it is a refined carbohydrate with a high glycemic index and no fiber. This allows your body to digest and absorb the starch very quickly, leading to a rapid increase in blood glucose levels.

Yes, a persistent craving for cornstarch may be a sign of an eating disorder called pica. This is often linked to underlying nutritional deficiencies, such as iron or zinc deficiency, and requires a doctor's evaluation.

The most common digestive side effects include bloating, gas, and abdominal pain, especially from consuming it raw. Its lack of dietary fiber can also lead to constipation.

Consuming a diet high in refined carbohydrates like cornstarch can be detrimental to heart health. It is linked to higher triglyceride levels and an increased risk of heart disease.

Healthier alternatives include oat flour, whole wheat flour, and almond flour. These options offer more nutritional value, including fiber and protein, which help mitigate some of the negative effects of refined carbohydrates.