Corn Syrup and the Low FODMAP Diet
You have probably read that HFCS (high fructose corn syrup) is not recommended while following the low FODMAP diet but perhaps you have wondered what about “regular”corn syrup? Is it low FODMAP? Is it the same thing?
Is Corn Syrup Low FODMAP?
Yes, corn syrup is considered low FODMAP, because it is predominately made of glucose.
Is High Fructose Corn Syrup Low FODMAP?
High fructose corn syrup is typically about 55 percent fructose and 40 percent glucose, making it high FODMAP.
Corn syrup and HFCS are not the same product.
What is HFCS?
I am sure you have read many articles railing against high-fructose corn syrup. The main thing to know is that it is not the same as regular old corn syrup, such as the Karo, shown above.
High-fructose corn syrup begins as corn syrup but it is then further processed and modified. It is broken down enzymatically to create two different forms of sweeteners: fructose and glucose and results in the fructose being in higher proportion, making it off limits for FODMAPers.
HFCS was originally developed as a lower cost substitute for sugar, which is why you see it in the ingredient lists of so many junk foods. It is the fructose that has been linked to obesity as well as other health related issues such as Type 2 diabetes, all of which can increase the risk of heart disease.
Controversy exists even for those not following the low FODMAP diet. And of course, if you react to fructose, you will not want it in your diet. “Regular” corn syrup, like the Karo mentioned, does not have this stigma attached.
Karo Brand & History of High Fructose
We use Karo brand, which contains no high-fructose corn syrup. If you read their website’s articles carefully they say that the brand did not contain any high fructose syrup when they introduced the product in 1902, and they do not now.
There was, however, an interim period during which their Karo syrup contained high-fructose corn syrup. I am not sure of those dates, as they have not disclosed them. This might be why some are confused, thinking that their product contains high-fructose corn syrup now. It does not.
High Fructose Corn Syrup Is High FODMAP, BUT…
High fructose corn syrup (HFCS) is considered high FODMAP, yet ketchup containing HFCS is given a Green Light by Monash, and in fact used to show the same low FODMAP serving size as ketchup made with sugar, however, subsequent lab testing actually shows the HFCS ketchup to have a slightly larger serving (18 ml vs 16 ml)! The diet is all about serving sizes and thresholds. Read more in our article, What Is A Low FODMAP Serving Size?
My focus here is to help you understand what these two ingredients are – corn syrup and HFCS – and how best to use them, or not!
We Use Corn Syrup, But Not HFCS
You will find recipes on FODMAP Everyday calling for corn syrup – such as in Pecan Pie or Hot Fudge Sauce. As an invert sugar (low FODMAP) it prevents crystallization and is very useful in some recipes.
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You May Want To Read: Understanding Fructose Intolerance, A Lesser Known Dietary Trigger
What Corn Syrup Does in Recipes
Corn syrup appears in many recipes not just for sweetness, but because it changes how sugar behaves during cooking and baking. In many cases it is used for texture, stability, and moisture rather than flavor.
It Prevents Sugar Crystallization
Granulated sugar (sucrose) naturally wants to form crystals when heated and cooled. That can make sauces, frostings, and candies turn gritty. Corn syrup is mostly glucose, and those glucose molecules interfere with sucrose lining up and forming crystals. Even a small amount can keep caramel, fudge, pecan pie filling, and candy smooth and glossy.
It Creates a Softer Texture
Corn syrup is hygroscopic, meaning it attracts and holds water. This helps baked goods and candies stay tender rather than drying out or becoming brittle. That is why it is common in chewy cookies, marshmallows, caramels, and nougat. Try our Low FODMAP Chewy Peanut Butter Cookies.
It Adds Body Without Too Much Sweetness
Corn syrup is less sweet than table sugar, which lets recipe developers add thickness and moisture without making desserts cloying. In recipes like pecan pie filling or caramel sauce, it provides structure and shine while keeping sweetness balanced.
It Helps Foods Stay Fresh Longer
Because corn syrup holds onto moisture, foods made with it tend to stay soft longer. This is one reason it is widely used in commercial baking and packaged foods.
It Helps Candy Cook Predictably
Candy making depends on precise sugar chemistry. Corn syrup helps sugar mixtures cook more reliably and reduces the chance of grainy or overly brittle results.
Glucose-Fructose
On labels in certain countries, such as Canada, you might find an ingredient listed on a prepared product as “glucose-fructose”. This is high fructose corn syrup and should be avoided.
In Europe, HFCS might be listed as isoglucose. In Germany, the fructose content in glucose-fructose syrup is usually between 9 and 35%, while the glucose content is 30 to 45%.
The fructose content in glucose-fructose syrup can vary depending on the specific syrup and its production methods. In some cases, the fructose content may be as low as 42% in the U.S., but there is no way to know.
Our suggestion is that if you see the words “glucose-fructose” that you steer clear, if fructose is an issue.
What To Know About Sugar, Corn Syrup & FODMAPs
- Over consumption of sugar of any sort is not recommended. Practice moderation and if you are following the low FODMAP diet, understand the FODMAP content of the foods that you do choose to eat.
- We think the biggest issue is with hidden sugars – in sodas, snack foods, even commercially prepared bread! High-fructose corn syrup is often used in this way. Become a label reader. You don’t want these in your diet whether you are a FODMAPer or not.
- Moderation is key and we have no problem using regular corn syrup in our occasional cooking and baking.
We would rather have a slice of real low FODMAP pecan pie or drizzle hot fudge sauce on lactose-free ice cream than to find out that we ate the equivalent of sugars from ketchup, bread and other processed foods.
