Why a 1:1 glucose-to-fructose ratio?

Honey dripping from a dipper beside a jar of maple syrup and honeycomb

Glucose and fructose are absorbed through different routes in the gut, so a gel with both can deliver more usable fuel per hour than a gel with only one. That is the whole reason ratios show up on gel labels.

Two doors instead of one

Glucose crosses the gut wall through one type of transporter, and that route can only move so much per hour. Fructose uses a different transporter. Feed both sugars and you're using two doors instead of crowding one. Researchers call these "multiple transportable carbohydrates".

What the studies found

In a 2008 study, eight trained cyclists rode for two hours and then did a time trial. When they drank glucose plus fructose, they finished the time trial 8% faster than when they drank the same amount of glucose alone.

A 2015 review pulled together 14 studies of efforts lasting 2.5 to 3 hours. Drinks with fructose-to-glucose ratios between 0.5:1 and 1:1 improved power by 1% to 9% compared with glucose-only drinks carrying the same calories. Mixes between 0.7:1 and 1:1 were absorbed fastest, and a ratio near 0.8:1 did best at high intake rates.

Where 1:1 fits

A 1:1 ratio sits inside the range that research supports, at the fructose-rich end. It is also close to what honey and maple syrup supply on their own, which is why we didn't need to add refined sugars, maltodextrin or other fruit concentrates to get there.

What the research doesn't say

  • It matters most when you're eating a lot. The benefit of mixed sugars is clearest at high intakes over long efforts. At 30 to 60g an hour, most carbohydrate types work.
  • Most studies used drinks, not gels, and most participants were male cyclists.
  • No single ratio is proven best for everyone. The studies compare ranges, and individual tolerance varies.

These studies tested glucose and fructose mixes in general. They were not tests of RANN.

What to do with this

If you fuel at more than about one gel an hour, check that your gel contains both glucose and fructose sources. Then test it in training, because how your own stomach responds matters more than a number on a label.

This article is general information, not medical advice.

Sources

  1. Gatorade Sports Science Institute. Dietary carbohydrate and the endurance athlete: contemporary perspectives. Sports Science Exchange 231, 2022. View article
  2. Currell K, Jeukendrup AE. Superior endurance performance with ingestion of multiple transportable carbohydrates. Med Sci Sports Exerc, 2008. View abstract
  3. Rowlands DS, et al. Fructose-glucose composite carbohydrates and endurance performance: critical review and future perspectives. Sports Med, 2015. View abstract
● Founding Batch presale now open ● Free US shipping over $50 ● Made in San Diego, CA
← Fuel School The Science · 2 min read ·

Why a 1:1 glucose-to-fructose ratio?

Your gut absorbs glucose and fructose through different routes. Here's what the research says about combining them, and why RANN uses a 1:1 ratio.

Glucose and fructose are absorbed through different routes in the gut, so a gel with both can deliver more usable fuel per hour than a gel with only one. That is the whole reason ratios show up on gel labels.

Two doors instead of one

Glucose crosses the gut wall through one type of transporter, and that route can only move so much per hour. Fructose uses a different transporter. Feed both sugars and you're using two doors instead of crowding one. Researchers call these "multiple transportable carbohydrates".

What the studies found

In a 2008 study, eight trained cyclists rode for two hours and then did a time trial. When they drank glucose plus fructose, they finished the time trial 8% faster than when they drank the same amount of glucose alone.

A 2015 review pulled together 14 studies of efforts lasting 2.5 to 3 hours. Drinks with fructose-to-glucose ratios between 0.5:1 and 1:1 improved power by 1% to 9% compared with glucose-only drinks carrying the same calories. Mixes between 0.7:1 and 1:1 were absorbed fastest, and a ratio near 0.8:1 did best at high intake rates.

Where 1:1 fits

A 1:1 ratio sits inside the range that research supports, at the fructose-rich end. It is also close to what honey and maple syrup supply on their own, which is why we didn't need to add refined sugars, maltodextrin or other fruit concentrates to get there.

What the research doesn't say

  • It matters most when you're eating a lot. The benefit of mixed sugars is clearest at high intakes over long efforts. At 30 to 60g an hour, most carbohydrate types work.
  • Most studies used drinks, not gels, and most participants were male cyclists.
  • No single ratio is proven best for everyone. The studies compare ranges, and individual tolerance varies.

These studies tested glucose and fructose mixes in general. They were not tests of RANN.

What to do with this

If you fuel at more than about one gel an hour, check that your gel contains both glucose and fructose sources. Then test it in training, because how your own stomach responds matters more than a number on a label.

This article is general information, not medical advice.

Sources

  1. Gatorade Sports Science Institute. Dietary carbohydrate and the endurance athlete: contemporary perspectives. Sports Science Exchange 231, 2022. View article
  2. Currell K, Jeukendrup AE. Superior endurance performance with ingestion of multiple transportable carbohydrates. Med Sci Sports Exerc, 2008. View abstract
  3. Rowlands DS, et al. Fructose-glucose composite carbohydrates and endurance performance: critical review and future perspectives. Sports Med, 2015. View abstract

Fuel the last mile.

Honey and maple. 30g carbs, 1:1 glucose to fructose, 150mg sodium.

Shop RANN

More from Fuel School

Race DayYour marathon fueling plan, mile by mileFueling BasicsWhat is an energy gel, and when do you need one?