The Truth About Fruit Sugar vs. Refined Sugar.

G'day mate,

15 years ago I published a book called Dudefood, created to “Empower the Modern Man” and while the hairstyle has definitely changed… my take on sugar hasn’t. But one of the biggest questions I still face is: Is fruit sugar considered bad? Today we are going to break this one down.

In this weeks Newsletter (4 min read)

🍏 The difference between fruit sugar and refined sugar

🔬 How bioavailability changes the whole conversation

🍋 My no-sugar-added dessert that uses lemon to sweeten

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Fruit Sugar ≠ Refined Sugar

I’ve always believed one of the biggest wins for our health is cutting refined sugar.
That doesn’t mean cutting taste or joy—it means knowing where your sweetness is coming from. Fruit often gets lumped in with the “bad sugar” crowd, but let’s clear that up. Yes, fruit has sugar. But it also has structure—fiber, water, antioxidants, and nutrients that change how your body processes it. Plus, it contains a natural blend of:

• Fructose – processed in the liver

• Glucose – fuels your muscles and brain

• Sucrose – a mix of both

But here’s the kicker: in fruit, these sugars come bundled with tools your body understands—fiber slows absorption, hydration supports digestion, and vitamins do the background work.

Now compare that to 5g of sugar in a candy bar:

• Candy = sugar alone, fast spike, fast crash

• Fruit = sugar + nutrients, slower burn, sustained energy

Quick example:

• Apple: ~5g sugar + fiber + vitamin C + hydration

• Apple juice: sugar, no fiber—fast spike

• Gummy bears: just sugar—no benefits

Even if the labels match, the impact is totally different. Refined sugar hits like petrol on a fire. Fruit sugar? It’s a slow-burning log—clean, steady energy. That’s where bioavailability comes in—and why fruit hits different.

Bioavailability is the Real Story

Last week we talked about bioavailability—how much of a nutrient your body can actually absorb and use.

Here’s the thing: when you eat refined sugar, it hits your system fast—already broken down, no fiber to slow it down. Blood sugar spikes, insulin floods in, and your energy crashes soon after. Repeat that cycle long enough, and it can lead to insulin resistance, inflammation, and metabolic issues. Fruit doesn’t work like that.

Fruit sugar is less “available” all at once—it’s locked in a fibrous, watery structure your body has to break down gradually. Think of it like unwrapping layers. That slow process means:

• A slower glucose release

• Lower insulin spikes

• More stable energy

And fruit brings more than just fuel—it delivers vitamins, minerals, antioxidants, and gut-supporting fiber. That combo supports long-term health, not just short-term energy. So when we talk bioavailability, it’s not just how much sugar is in the food—it’s how it’s delivered. And fruit delivers it in a way your body knows how to handle.

But here’s the nuance: There are moments—like long runs, marathons, or between intervals—when you do want fast sugar. Refined carbs (like gels or white bread) can serve a purpose: delivering glucose to muscles immediately. That’s sugar as a performance tool—not sugar hiding in your granola bar on a Tuesday afternoon. Big difference.

When Fruit Is a Performance Tool

Here’s where fruit becomes more than a sweet treat. When timed right, it becomes a functional tool.

• Pre-run: Banana + peanut butter = fast fuel + staying power

• Post-lift: Berries + protein = recovery support (antioxidants + glycogen refuel)

• Late-night: Cherries + yogurt = melatonin + tryptophan = better sleep

You don’t need to be afraid of fruit. You just need to be intentional.

If you're training hard, especially endurance work, glucose is your friend. But whole food forms like fruit give you fuel plus nutrients. Refined sugar gives you the spike without the support.

Recipe: Fruit Soup from Dudefood HERE

Cals: 115 I Protein: 1.5g I Carbs: 29g I Fat: 0.5g I

In light of the whole fruit vs refined sugar battle, here’s one of my favorite recipes—one I’ve been making since the early DudeFood days. It’s simple, sweet, and built around one powerful ingredient: lemon. Lemon enhances natural sweetness through acidity. It tricks your tastebuds—in the best way—and lets you skip the sugar altogether.

Quick Notes

🎬 New YouTube video is out from my trip to Switzerland with On Running. I attempt an Olympian’s hardest track workout in the Swiss Alps. I was deep in the pain cave, but I’m in my training block for a sub-3 marathon, so we got it done. WATCH HERE.

🌡️ We’re in another heatwave on the East Coast — it’s 100° F in Manhattan today — so make sure you’re staying hydrated and taking your electrolytes. For my guide on how to stay hydrated during hot summer days CLICK HERE.

✍️ I’m guest posting on Brady Holmer’s newsletter Physiologically Speaking on Friday. Brady’s newsletter is one of my go-to’s for science-backed info on health and human performance. Dude is also a savage athlete. SUBSCRIBE HERE.

#EatGoodFeelGood

DC