Can Instant Coffee Raise Blood Sugar? The Full Explanation

December 14, 2025 •

3 min read

According to a study involving nearly 188,000 adults, long-term moderate coffee consumption has been linked to a reduced risk of cardiometabolic diseases like type 2 diabetes. However, when asking if instant coffee can raise blood sugar, the answer is more complex and depends on individual factors and what you add to your cup.

Quick Summary

Instant coffee’s effect on blood sugar is nuanced; caffeine may cause a short-term spike, but long-term use can improve glucose metabolism. The most significant blood sugar impact comes from sweeteners and creamers, not the coffee itself.

Key Points

Caffeine's Dual Effect: Caffeine can cause a temporary, short-term blood sugar spike, but long-term, coffee's antioxidants may help improve insulin sensitivity.
Additives are Key: Sugars, syrups, and high-carb creamers are the primary cause of blood sugar spikes associated with coffee, not the instant coffee itself.
Decaf is Safer: For those highly sensitive to caffeine's effects on blood sugar, switching to decaffeinated coffee may provide benefits without the acute glucose rise.
Mindful Add-Ins: To minimize impact, drink instant coffee black or use low-carb, unsweetened alternatives like stevia and almond milk.
Track Your Response: People with diabetes should monitor their blood sugar levels after drinking instant coffee to understand their body's individual reaction.
Long-Term vs. Short-Term: Acute caffeine intake can impair insulin sensitivity, but studies show long-term coffee drinkers have a lower risk of type 2 diabetes.

The Dual-Edged Sword of Caffeine

Caffeine, found in instant and brewed coffee, can temporarily increase blood sugar by triggering the release of stress hormones. These hormones signal the liver to release glucose. This effect is usually minor for healthy individuals, but can cause a more noticeable spike in those with insulin resistance or type 2 diabetes. Research shows that even regular coffee drinkers with type 2 diabetes may still experience this.

The Long-Term Paradox: Health Benefits

Despite short-term effects, long-term studies link habitual coffee drinking to a lower risk of type 2 diabetes. This applies to both caffeinated and decaffeinated coffee, suggesting other compounds are beneficial. Coffee contains antioxidants like chlorogenic acid, which may improve insulin sensitivity and reduce inflammation, potentially counteracting caffeine's immediate effect over time.

The Real Culprits: Added Sugars and Creamers

Significant blood sugar spikes from coffee are often due to additives, not the coffee itself. Sugary syrups, creamers, and even large amounts of milk add carbohydrates and fat, leading to rapid blood glucose increases. One study found that adding sugar and creamer increased the likelihood of poor A1C management compared to drinking black coffee. Some milk alternatives like oat milk can also be higher in carbs.

The Differences Between Instant and Brewed Coffee

Instant coffee is dehydrated brewed coffee, which slightly alters its composition. Brewed coffee might have higher levels of beneficial compounds like chlorogenic acid. However, studies suggest both instant and brewed coffee can help prevent type 2 diabetes long-term.

Practical Tips for Managing Blood Sugar with Coffee

Mindful choices allow individuals to enjoy instant coffee while managing blood sugar.

Monitor your glucose: Diabetics should check blood sugar after coffee to understand their personal response.
Drink black or unsweetened: Plain black coffee is best. Use a calorie-free sweetener if needed.
Choose creamers wisely: Opt for low-carb, unsweetened plant-based milk instead of dairy or sugary creamers.
Hydrate first: Drinking water before coffee supports glucose metabolism.
Pair with food or activity: Having coffee with a meal or exercising afterward can help manage potential blood sugar changes.

Comparison Table: Additives and Blood Sugar Impact


Additive	Carbohydrates	Sugars	Calories	Blood Sugar Impact
Plain Black Instant Coffee	Low/Negligible	0g	Low	Minimal to temporary slight increase (from caffeine)
Sugar	High	High	High	Significant and rapid spike
Sweetened Syrups	High	High	High	Significant and rapid spike
High-Sugar Creamers	High	High	High	Significant and rapid spike
Unsweetened Almond Milk	Low	0g	Low	Minimal/Negligible
Unsweetened Soy Milk	Low	0g	Low	Minimal/Negligible
Oat Milk	Moderate	Moderate	Moderate	Moderate increase (depending on amount)
Artificial Sweeteners (e.g., Stevia)	0g	0g	0g	Minimal to no impact (but individual response varies)

Conclusion

While instant coffee's caffeine can cause a temporary blood sugar rise, especially in diabetics, the long-term benefits of coffee, including a lower risk of type 2 diabetes, are notable. The main factor influencing blood sugar from coffee is the addition of sugars, syrups, and creamers. Choosing black or unsweetened options allows individuals, including those with diabetes, to enjoy instant coffee with minimal impact on blood sugar control. Consulting a healthcare provider for tailored advice is always recommended.

Frequently Asked Questions

Plain, black instant coffee has a minimal effect on blood sugar. Any slight, temporary rise is due to the caffeine content, which affects individuals differently, especially those with diabetes.

Caffeine stimulates the release of stress hormones like adrenaline, which can signal the liver to release stored glucose into the bloodstream, causing a temporary rise in blood sugar.

While the fundamental effects are similar, brewed coffee may contain slightly higher levels of beneficial antioxidants like chlorogenic acid. However, large studies indicate both can lower the long-term risk of type 2 diabetes.

Artificial sweeteners do not typically raise blood sugar. However, some foods containing them may have other ingredients that do, so it's best to read labels. Individual responses can also vary.

To enjoy coffee without a significant blood sugar spike, drink it black, opt for decaf, or use low-carb, unsweetened add-ins like almond milk and stevia. Monitoring your personal glucose response is also crucial.

Some studies suggest that regular, moderate coffee consumption is associated with a lower risk of developing type 2 diabetes over the long term, due to compounds like antioxidants.

The main issue for blood sugar control lies with common, high-sugar additions like syrups and creamers, not the instant coffee powder itself. These additives can cause rapid and significant blood sugar increases.