Stay curious!

Oat milk: Healthy hype or hidden sugar bomb?

Ingredients for homemade oat milk, including rolled oats, vanilla, and brown sugar, displayed on a tray — plant-based milk alternative.

Is oat milk secretly bad for you? Or is it just another health trend being unfairly bashed? In this blog, we’ll break down the facts about oat milk, sugar, and blood sugar spikes — and whether you should worry.

What is oat milk?

Oat milk is a plant-based milk alternative made from just two simple ingredients: oats and water. Because it’s technically not “milk,” you’ll often see it labeled as an oat drink in stores — but most people (and this blog!) will call it oat milk. It’s a popular choice for coffee, cereal, baking, or just drinking on its own.

A quick history of oat milk

Oat milk was invented in the 1990s by Swedish scientist Rickard Öste, who was researching lactose-free alternatives. He later founded Oatly, one of the most popular oat milk brands worldwide.

What’s in oat milk?

At its core, oat milk contains:

  • Oats
  • Water

Commercial oat milk may also include:

  • Stabilisers to extend shelf life
  • Vegetable oils for creaminess
  • Added sugar or sweeteners (in some versions)
  • Added vitamins and minerals like calcium, vitamin D, B2, and B12

Nutritionally, oat milk is:

  • Lactose-free
  • A source of dietary fibre, particularly β-glucan (which may help lower cholesterol)
  • Contains unsaturated fats and bioactive compounds

However, it also: 

  • Lacks natural calcium and some vitamins found in cow’s milk
  • May require fortification to fill these nutritional gaps

Quick tip:

If you’re drinking oat milk for calcium, shake the carton well before pouring! Added calcium often settles at the bottom. Plus, oats naturally contain phytic acid, which can slightly block calcium absorption. And not all added calcium is absorbed equally — calcium carbonate is better absorbed than tricalcium phosphate.

How much sugar is in oat milk?

Oats naturally contain carbohydrates. During oat milk production, some of these carbs are broken down into sugar. The sugar content varies by brand:

  • Oatly Original: 3.4 g sugar per 100 ml
  • Rude Health Organic Oat Drink: 4.6 g sugar per 100 ml
  • Alpro Oat No Sugar: 0 g sugar per 100 ml

For comparison:

  • Cow’s milk: 4.7 g sugar per 100 ml
  • Grape juice: 16 g sugar per 100 ml

So, oat milk is not a sugar bomb — especially considering how little we usually use (a splash in coffee or cereal).  Often, your granola has way more sugar than your oat milk.

Does oat milk spike your blood sugar?

A lot of concern about oat milk and blood sugar started when a French influencer shared dramatic glucose monitor results after drinking oat milk. But here’s what’s important to know:

  • Oat milk is higher in carbs than some other plant-based milks because it’s made from oats.
  • That starch breaks down into sugar during processing and digestion, which can raise blood sugar.
  • However, oat milk has a moderate glycemic index and a low glycemic load — meaning the overall impact on blood sugar is small.

For most healthy people, a cup of oat milk won’t be a problem — especially if you’re eating it alongside other foods like oats, nuts, or protein, which slow down sugar absorption. Even if you drink oat milk on an empty stomach, it’s normal for your blood sugar to rise and fall. That’s how your metabolism works! Your body releases insulin to bring sugar levels back down — it’s a healthy, natural process.

When to be careful

If you have diabetes or insulin resistance, oat milk’s higher carb content may not be the best option. But for everyone else, an oat milk latte is not the same as drinking a Coke.

Is oat milk worse than coke?

No, that claim is complete nonsense. Not only does oat milk contain far less sugar than coke, but it also provides fibre, vitamins, and healthy fats. And realistically, most people consume oat milk in small amounts — in coffee or cereal — while sodas are often consumed in much larger quantities.

Final thoughts

If you’re healthy and like oat milk, there’s no need to worry about having it daily. But it’s always worth checking the label — not all oat drinks are the same. Some have added sugar, some don’t. Some are fortified, others aren’t. For the best results, pair oat milk with other nutritious foods like oats, yogurt, seeds, or nuts to slow down sugar absorption.

Curious about how oat milk is made?

I actually tried making oat milk myself at home! Check out my Instagram reel where I show the process — and whether I’d recommend making it yourself.

References

Leave a comment