We read the label so you don't have to. You're welcome.
Here's something most athletes never do.
Read the back of their gel.
Not the front, with the bold flavour name and the fast-looking font. The back. The actual ingredient list. The one written in size 6 font that you need good lighting and a magnifying glass to get through.
We did it for you. And it's not pretty.
Let's Start With GU
GU is one of the most popular gels in the world. Used by hundreds of thousands of athletes every weekend. Here's what's in a standard flavour:
Maltodextrin, Water, Fructose, L-Leucine, Natural Flavors, Potassium Citrate, Sodium Citrate, Citric Acid, Calcium Carbonate, L-Valine, Sea Salt, Gellan Gum, L-Isoleucine, Sunflower Oil, Sodium Benzoate (Preservative), Potassium Sorbate (Preservative)
Count them. That's 16 ingredients. Sixteen. For something you eat to fuel a run.
Let's break down the ones that should make you pause.
Maltodextrin: First Ingredient, Biggest Problem
We covered this in depth in our first article, but the short version: maltodextrin is a processed white powder made from chemically broken-down starch. It has a glycemic index higher than table sugar, and peer-reviewed research has linked long-term consumption to gut inflammation, damaged intestinal lining, and disrupted gut bacteria.
It's also the first ingredient in GU. Meaning it makes up more of the product than anything else.
"Natural Flavors": The Most Misleading Two Words in Food
This one sounds harmless. Even friendly.
Here's the reality. Under FDA regulations, "natural flavors" can legally include over 100 different chemical compounds, as long as they were originally derived from a natural source at some point in the process. That original source could be a fruit. It could also be a beaver's castor gland. Both are technically "natural."
The label tells you nothing about what the flavour actually is, how it was processed, or what else came along with it.
When a brand uses "natural flavors" instead of just saying "strawberry" or "lemon," it usually means the flavour isn't coming from the actual fruit. It's coming from a lab that starts with something natural and ends up with something very different.
Sodium Benzoate and Potassium Sorbate: Your Preservatives
These two show up together in GU, SiS, PowerBar, and most mainstream gels. They exist for one reason: shelf life. They stop the product going off, which is great for the manufacturer and the retailer.
But here's what the research says.
A peer-reviewed study published in Comprehensive Reviews in Food Science and Food Safety found that sodium benzoate can react with ascorbic acid in drinks to produce benzene, a known carcinogen. The same research raised concerns about its potential neurotoxic and mutagenic effects in cell and organism studies. Precision Fuel & Hydration
A separate PMC study found that sodium benzoate was linked to mutagenic effects, oxidative stress, disrupted hormones, and reduced fertility across multiple independent studies. Precision Fuel & Hydration
And perhaps most relevant for athletes specifically: both sodium benzoate and potassium sorbate have been shown to cause increases in oxidative stress in model organisms, with damage to mitochondria that could potentially contribute to mitochondrial disease. Both additives have also been reported to activate inflammatory pathways in liver tissue. Precision Fuel & Hydration
Think about what that means for you as an endurance athlete. You are already putting your body under significant oxidative stress every time you train. Your mitochondria are working overtime. And your fuel is adding to that load rather than reducing it.
The FDA says the amounts in food are safe. Independent researchers keep finding reasons to ask more questions. For a product you're taking every 30 minutes for hours at a time, that's not a trade-off worth making.
Gellan Gum, Sunflower Oil, and the Rest
These are what food scientists call "functional ingredients." They don't fuel you. They make the gel look, feel, and behave the way the manufacturer wants it to. Gellan gum is a thickener. Sunflower oil helps texture. Citric acid adjusts acidity so the flavour tastes right.
None of them belong in a performance fuel. They belong in a processed food factory.
Now Look at 2THRV
Organic Maple Syrup. Organic Dates. Organic Berries. Organic Lemon Juice. Mineral Salt.
Five ingredients. Every single one of them is a whole food. Every single one serves a performance purpose.
There are no preservatives because the product is made fresh and doesn't need to sit on a shelf for 18 months. There are no "natural flavors" because the flavour comes from real fruit. There are no thickeners because the texture comes from the food itself.
Nothing is there unless it earns its place.
The Simple Test
Next time you pick up a gel at a race expo or a run store, flip it over. Ask yourself two questions:
- Can I pronounce every ingredient on this list?
- Do I know what each one actually does in my body?
If the answer to either is no, that should tell you something.
Your gut health, your mitochondria, your long-term wellbeing as an athlete. They all start with what you choose to put in your body.
Make it count.
[Shop 2THRV — five ingredients, nothing to hide.]
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