News Nutrition

Forget 2:1 Glucose Fructose gels, you really need 5:4

15 July 2021
the5krunner

Forget 2:1 Glucose Fructose Gels, You Really Need 5:4SiS 5:4 Maltodextrin to Fructose

Just when you thought it was safe to have a gel, SiS come and spoil your party. Like you, I have been blindly taking as true the not-so-old adage that “glucose:fructose ratios need to be 2:1 to maximise how your gut absorbs carbs”.

Well, 2:1 ratios are only able to allow 62% of ingested carbs to be oxidised. Change the ratio of maltodextrin:fructose to 5:4 and that’s boosted to 74%…a 20% increase.

These new ratios are contained in SiS’s reformulated Beta Fuel.

Here is the research by O’Brien, Stannard et al which concludes:

Enhanced high-intensity endurance performance with a 0.8 ratio fructose-maltodextrin-glucose drink is characterized by higher exogenous-CHO oxidation efficiency and reduced endogenous-CHO oxidation.

 

Sis sell the stuff in 3 formats

  • Energy Drink Powder – to minimise GI distress
  • Gels – with nootropics for improved cognitive function
  • Chew bars – an easy-to-chew formula 

My Personal Take

If you are a high-level athlete competing on the edge this will probably make a difference. To you and me …less so.

If we are competing in Olympic distance events or shorter I guess there’s no point either

That said I didn’t know that energy drink powders aided GI distress and might switch to that next year when my gels have run out. I do get GI distress if I fuel only with gels and my current strategy is to alternate them with something solid, which seems to help.

Check Out How Much It Costs

It’s not crazily expensive and comes in at £2 a gel, probably about $/Eu2.50/gel

 

Forget 2:1 Glucose Fructose Gels, You Really Need 5:4

 

 

 

Last Updated on 25 January 2026 by the5krunner

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2 thoughts on “Forget 2:1 Glucose Fructose gels, you really need 5:4”

  1. So SIS are now admitting that all their marketing about 2:1 being optimal was bollocks!
    Wonder what the magic ratio will be next time they decide they need to increase sales 😉

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