What is Regular Sugar (Sucrose)?
Regular table sugar, or granulated sugar, is chemically known as sucrose. It is a disaccharide, meaning it is composed of two simpler sugar molecules, or monosaccharides, bonded together: one molecule of glucose and one molecule of fructose. Sucrose is derived from either sugarcane or sugar beets, which are refined to produce the familiar white, crystalline substance.
The refining process for regular sugar involves extracting the sucrose-rich juice from the plants, purifying it, and then boiling it to form crystals. The natural molasses is removed, resulting in a product that is almost entirely pure sucrose. When consumed, the digestive system breaks the bond between the glucose and fructose molecules before they can be absorbed into the bloodstream.
What is Corn Sugar?
The term "corn sugar" is more ambiguous and can refer to a few different products, primarily dextrose or high-fructose corn syrup (HFCS). Both are derived from corn starch through a multi-step enzymatic process.
Dextrose
Dextrose is pure glucose, a simple monosaccharide. Because it is a single sugar molecule, yeast can metabolize it directly, making it a popular choice in brewing. Dextrose is also used as a medical treatment for low blood sugar and as a supplement for athletes. In food manufacturing, it's used in products like baked goods and confectionery.
High-Fructose Corn Syrup (HFCS)
HFCS is not the same as corn syrup, which is almost entirely glucose. Instead, HFCS is produced by adding enzymes to corn syrup to convert some of the glucose into fructose. The most common types are HFCS 42 (containing 42% fructose) and HFCS 55 (containing 55% fructose), which are found in processed foods and sodas, respectively. Unlike the bonded molecules in sucrose, the glucose and fructose in HFCS exist as separate, free-floating molecules.
Processing and Cost
The fundamental difference in how these sweeteners are produced has significant implications for cost and application in the food industry. Regular sugar (sucrose) requires agricultural harvesting and a refining process involving boiling and crystallization. The price of sucrose is subject to agricultural factors and market forces.
High-fructose corn syrup, on the other hand, is made from corn, which is a highly subsidized crop in the United States. This makes HFCS a cheaper sweetener to produce than sugar, leading many food and beverage manufacturers to switch to it for economic reasons. The cost-effectiveness of HFCS has made it a prevalent ingredient in a vast range of processed foods and drinks.
Metabolic and Health Impacts
For practical purposes, consuming either added sucrose or added HFCS has a very similar effect on the body. While the molecules in sucrose are bonded and the molecules in HFCS are free, the digestive system quickly breaks down sucrose into its constituent glucose and fructose anyway, leaving your body to process the same two simple sugars.
However, it is the excessive consumption of added sugars from any source, including both corn and regular sugar, that is detrimental to health. Studies have consistently linked high intake of added sugars to several health concerns:
- Weight gain and obesity: Both HFCS and sucrose contribute calories that can lead to weight gain when consumed in excess.
- Type 2 Diabetes: Excessive sugar intake is linked to insulin resistance and a higher risk of developing type 2 diabetes.
- Fatty Liver Disease: The liver metabolizes fructose, and an oversupply can lead to fat accumulation in the liver, contributing to non-alcoholic fatty liver disease.
- Heart Disease Risk: High added sugar consumption is associated with increased triglycerides and other risk factors for heart disease.
One minor metabolic difference suggested by some studies is a potential for higher C-reactive protein (CRP), a marker of inflammation, with HFCS compared to sucrose, though findings are not conclusive. But given the similar fructose and glucose ratios in common HFCS and sucrose, most experts agree that from a health perspective, the source is less important than the total amount consumed.
What does this mean for consumers?
For the average consumer, focusing on reducing overall added sugar intake is more impactful than fixating on the specific source. Label-reading is essential, as HFCS is a common hidden ingredient in many processed products, not just obvious sweets. Ultimately, whether it's cane sugar or corn-based, sugar is sugar, and moderation is key for a healthy diet.
Comparison Table
| Feature | Regular Sugar (Sucrose) | Corn Sugar (Dextrose/HFCS) |
|---|---|---|
| Source | Sugar cane or sugar beets | Corn starch |
| Chemical Type | Disaccharide (glucose + fructose, bonded) | Monosaccharide (dextrose) or a mixture of free monosaccharides (HFCS) |
| Physical Form | Dry, granulated crystals | Crystalline powder (dextrose) or thick liquid (HFCS) |
| Common Use | Home baking, cooking, sweetening | Processed foods, sodas, baking (HFCS); brewing, medical use (dextrose) |
| Cost | Typically higher than HFCS | Generally cheaper due to subsidized corn |
| Metabolic Effect | Body breaks bond, absorbs glucose and fructose | Absorbed as free glucose and fructose |
| Health Impact | Harmful in excess, like all added sugars | Harmful in excess; effect on body largely similar to sucrose |
Conclusion
When examining the difference between corn sugar and regular sugar, the key takeaway is that both are composed of the simple sugars glucose and fructose. While they differ in their origin and chemical structure before digestion, the end result in the human body is remarkably similar. The decades-long debate over whether HFCS is 'worse' than sucrose has largely concluded that from a metabolic standpoint, the differences are minimal, and excessive consumption of any added sugar is the primary health concern. For consumers, this reinforces the importance of monitoring total added sugar intake rather than focusing solely on the source. Whether your sweetener comes from a cane field or a cornfield, moderation remains the most important dietary principle.
To learn more about the broader impact of added sugars on health, explore the Added Sugars and High-Fructose Corn Syrup information sheet from the UC Davis Nutrition Department.
