What Happens If You Eat a Large Amount of Cornstarch?

October 22, 2025 •

4 min read

According to research, cornstarch is a highly refined carbohydrate with very little nutritional value. So, what happens if you eat a large amount of cornstarch? Consuming excessive amounts can lead to significant health issues, including blood sugar spikes, digestive problems, and potential long-term harm to heart health.

Quick Summary

Eating too much cornstarch can cause severe digestive problems, drastic blood sugar fluctuations, and lead to nutrient deficiencies due to its lack of fiber, protein, and vitamins. It may also indicate an underlying eating disorder known as pica, which warrants medical attention. Excessive, non-medical intake is not recommended and carries multiple health risks.

Key Points

Blood Sugar Spikes: Eating a lot of cornstarch can cause a rapid increase in blood sugar levels due to its high glycemic index and lack of fiber.
Digestive Issues: Consuming large quantities, especially raw, can lead to bloating, gas, stomach pain, and altered bowel movements because the body has difficulty digesting it.
Nutrient Deficiency: Cornstarch is calorie-dense but nutritionally empty, and replacing nutrient-rich foods with it can cause nutritional deficiencies over time.
Weight Gain: The high caloric content and low satiety can contribute to rapid and unhealthy weight gain if consumed in excess.
Heart Health Risks: Regular consumption of large amounts of refined carbohydrates, like cornstarch, can increase triglycerides and harm heart health in the long run.
Sign of Pica: A strong, persistent craving for cornstarch may be a symptom of pica, an eating disorder often linked to iron or zinc deficiency.

Immediate Consequences: Blood Sugar Spikes and Digestive Distress

When a person consumes a large amount of cornstarch, especially in its raw form, the body quickly processes this refined carbohydrate. Unlike whole grains which contain fiber to slow digestion, cornstarch is rapidly broken down, leading to a quick and significant spike in blood glucose levels. This is particularly dangerous for individuals with diabetes or insulin resistance, but it can negatively affect anyone's metabolic health over time.

Another immediate effect is the impact on the digestive system. Raw cornstarch is difficult for the body to digest, often leading to unpleasant gastrointestinal symptoms. The resistant starch in cornstarch passes into the large intestine where it is fermented by gut bacteria, producing gas and other byproducts. This can cause a range of discomfort, including:

Bloating
Gas
Stomach cramps
Diarrhea or constipation

Nutritional Deficiencies and Weight Gain

Cornstarch offers virtually no nutritional benefit beyond calories and carbohydrates. It is stripped of fiber, protein, vitamins, and minerals during processing. Replacing nutritious foods with large quantities of cornstarch can lead to significant nutrient deficiencies over time, as the body is not receiving the essential building blocks it needs to function properly. Furthermore, the high calorie content of cornstarch, combined with its lack of satiety, can lead to rapid and unhealthy weight gain. This weight gain is often due to an excessive intake of empty calories rather than balanced nutrition.

Potential Long-Term Health Risks

Sustained, excessive consumption of cornstarch can lead to more severe health problems. The chronic blood sugar spikes caused by cornstarch can contribute to insulin resistance and increase the risk of developing Type 2 diabetes. Additionally, diets high in refined carbohydrates have been linked to higher triglyceride levels, which are a known risk factor for heart disease. Over time, this dietary pattern can negatively impact heart health and contribute to systemic inflammation.

Psychological and Behavioral Factors: The Role of Pica

A persistent, compulsive craving for and consumption of non-food items like cornstarch is a recognized eating disorder called pica. The specific craving for starch is known as amylophagia. Pica is often a symptom of an underlying condition, such as iron-deficiency anemia, zinc deficiency, or other psychological factors. It is particularly common among pregnant women and individuals under high stress.

Consuming cornstarch as part of a pica habit can mask the underlying nutritional deficiency, delaying a proper diagnosis and treatment. If you or someone you know has a persistent craving for cornstarch, it is crucial to seek a medical evaluation to identify and address the root cause.

Cornstarch vs. Healthier Alternatives

When considering cooking or thickening agents, it is helpful to compare cornstarch with more nutritious options. This comparison table highlights the stark differences in nutritional profiles.


Feature	Cornstarch	Whole Wheat Flour	Oat Flour
Processing	Highly refined, stripped of nutrients	Contains germ and bran, retaining more nutrients	Made from whole oats, retains significant fiber
Glycemic Index	High, causes rapid blood sugar spikes	Lower than cornstarch due to fiber content	Much lower than cornstarch, stabilizes blood sugar
Fiber	Trace amounts	Significant amount	High in soluble fiber
Protein	Virtually none	Contains protein	High protein content
Vitamins & Minerals	Lacks essential micronutrients	Contains iron, folate, and B-vitamins	Rich in potassium, phosphorus, magnesium
Use Case	Powerful thickener, adds no flavor	Standard thickener, baking ingredient	Gluten-free alternative, baking, thickening

The Risks of Raw Cornstarch

While cooking cornstarch helps make it digestible and safe for consumption in small amounts, eating it raw carries additional risks. The texture is often unpalatable, and it can harbor harmful bacteria that are only killed during the cooking process. This increases the risk of foodborne illnesses, though reputable sources state this risk is generally low. The primary risk remains the high glycemic impact and poor digestibility when consumed raw in large quantities.

Conclusion

Eating a large amount of cornstarch is not recommended and can have several negative health consequences, both in the short and long term. The immediate effects include rapid blood sugar fluctuations and uncomfortable digestive issues. In the long term, regular, excessive intake can lead to nutrient deficiencies, weight gain, and increase the risk of chronic conditions like heart disease and Type 2 diabetes. Furthermore, a persistent craving for cornstarch, known as amylophagia, may be a sign of an underlying medical issue, such as pica, that requires professional evaluation. For cooking purposes, cornstarch is safe in moderation, but for any individual considering eating large quantities, it is vital to consult a healthcare provider to address any potential underlying causes and to seek healthier, more nutritious alternatives.

For more information on digestive issues caused by carbohydrates, consider reviewing resources like this comprehensive guide on resistant starch.

Frequently Asked Questions

Eating a lot of cornstarch is unhealthy because it is a highly processed, refined carbohydrate that can cause blood sugar spikes, contribute to weight gain, and lead to nutrient deficiencies due to its lack of fiber, protein, and vitamins.

Yes, eating too much cornstarch can cause weight gain. It is high in calories and carbohydrates but lacks fiber and other nutrients that promote a feeling of fullness, making it easy to consume an excess of calories.

A persistent craving for cornstarch can be a medical concern, as it is a form of pica, an eating disorder often linked to nutritional deficiencies like iron-deficiency anemia.

It is not recommended to eat raw cornstarch in large quantities. While small amounts in processed foods may be safe, raw consumption can cause digestive issues and, in theory, carries a slight risk of harmful bacteria.

Yes, cornstarch has a high glycemic index and contains no fiber, which means it is digested quickly and can cause a rapid and significant increase in blood sugar levels.

The long-term effects can include an increased risk of Type 2 diabetes, insulin resistance, and heart health issues due to high triglyceride levels, all stemming from a diet high in refined carbohydrates.

Yes, eating large amounts of cornstarch can cause digestive problems like diarrhea, as the body struggles to process the large amount of resistant starch, leading to fermentation by gut bacteria and irritation.