Ethan BrooksBy Ethan Brooks

Updated November 2026

Non fructose energy gels are gels that rely mainly on glucose, maltodextrin or other glucose-based carbohydrates instead of fructose. Many runners with gut sensitivity find these easier to digest during hard efforts. The key label check is the carbohydrate list: if fructose or high-fructose corn syrup appears near the top, the gel is not fructose-free.

Why Fructose Causes Stomach Problems

Your small intestine absorbs glucose through a transporter that works quickly and tolerates high volumes. Fructose uses a slower, separate pathway. When you take in more fructose than your gut can absorb in a given window, the excess moves into the colon, where bacteria ferment it. That fermentation produces gas, bloating, cramping and, for some athletes, urgent bowel movements. The problem gets worse under exercise, because blood flow shifts away from the gut toward working muscles.

Shopping for one? See our guide: Honey Stinger Energy Gels Review (2026): Pros and Cons.

What to Look for on the Label

Several factors determine whether a gel will sit well with you:

  • Carbohydrate source: Maltodextrin and glucose syrup are glucose-based. Fructose, agave, honey and high-fructose corn syrup are not.
  • Total carbohydrate per gel: Most gels provide roughly 20 to 25 grams. A gel with lower total carbs can be easier to tolerate in a single sitting.
  • Sugar alcohols and fiber: Some formulas add sorbitol, xylitol or inulin. These can cause the same issues as fructose in sensitive people, so check the full ingredient list.
  • Caffeine and sodium: Added caffeine or electrolytes can irritate some stomachs on their own, independent of the carbohydrate blend.

How to Test a Gel Before Race Day

Never try a new gel for the first time on race morning. A safer approach is to build tolerance during training:

  1. Start with one gel during a 60- to 90-minute run at your planned race pace.
  2. Take it at the same point in the run you plan to use on race day, typically around 45 minutes in.
  3. Follow it with the water volume you would actually carry or drink on race day.
  4. Repeat on at least two long runs before you commit to a gel for your goal event.
  5. If you have ongoing gut symptoms, such as frequent diarrhea or pain during exercise, see a doctor or sports dietitian before changing your fueling plan.

For timing and dosing ideas once you have a gel you trust, see When to Take Energy Gels: A Marathoner's Timing Guide. If you want background on the glucose-based carbohydrate often used in these products, Why Is There Maltodextrin in Energy Gels? Purpose and Trade-Offs explains the role it plays.

What We’d Use

Look for a glucose-based gel with a short, clearly labeled ingredient list, such as a maltodextrin-based formula from a sports nutrition brand that publishes its carbohydrate breakdown. View on Amazon

If you prefer a simpler option with fewer additives, a plain glucose gel with electrolytes can be a practical choice for training and racing. View on Amazon

FAQ

Are all energy gels with maltodextrin fructose-free?

Usually, but not always. Check the full ingredient list, because some formulas blend maltodextrin with fructose or fruit concentrates.

Can I switch to non fructose gels during a race?

It is safer not to. Switching fuel on race day adds an unknown variable. Test any new gel in training first.

Do I still need water with a non fructose gel?

Yes. Glucose absorption depends on fluid, so take each gel with the water volume you practiced with, and follow the manufacturer’s directions on the package.

Ready to choose one?

Ethan Brooks

About Ethan Brooks

Ethan Brooks is part of our editorial team and reviews and edits our marathon & half-marathon guides, checking product details against manufacturer specifications and owner feedback.