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Cereal Killer - Breakfast Blood Sugars

Does cereal have a place in a diabetic's kitchen?

To be honest, it’s difficult to know where to start when broaching the story of cereal. Why? Well, just have a bowl and check your blood sugars 2 hours later - it’s shocking.

But let’s do our due diligence and uncover the reality of what became arguably one of the most successful marketing campaigns of the 20th century, and in-turn contributed toward spiralling levels of chronic disease.

Where does cereal come from?

The modern version of ‘cereal’ started in the 1860‘s in America. A strict protestant sect known as the seventh-day Adventists believed protein led to impure thoughts. Two men, in particular, took note and saw a business opportunity, C.W Post and W.K. Kellogg (Yes, of Kellogg’s cornflakes).

By the late 20th century, they had sold billions of bowls of cereal and created a new normal ‘cold’ breakfast staple, far surpassing the more traditional ‘hot’ oats.

There are 4 types of cereal: flaked, puffed, shredded and granular. All are made from corn, wheat or rice. There are a few ways to make cereal but essentially they are put in a pressure chamber or cooker. Then baked, re-baked, squeezed or exploded to an inch of its life. All-natural nutritional value is lost, so vitamins are added in the final steps, and often coated in sweet flavours alongside syrups and sugars.

one 27g serving of Cap'n Crunch is almost entirely carbohydrate and contains 3 tsp sugar.

Why are we eating it?

The marketing for cereal has been an overwhelming success. They have continuously and relentlessly targeted children with prizes and brightly coloured boxes. Characters like 'Tony the Tiger' of Frosties fame began appearing which further embedded cereal into our children's hearts and the mainstream.

As our lives became busier and we had less free time, we turned to easy, fast food. Why not have a bowl of sweet-tasting cardboard drowning in milk to satisfy the hunger at breakfast. But wait, are we even hungry at breakfast or do we eat it because we've been told it's the most important meal of the day? funny that...

In the late 1990's and 2000's we started to see the emergence of 'healthy' and 'organic' marketed cereal. This has coincided with the trend of transparency across a lot of foods and the morality of our food choices.

To see a more in-depth timeline of cereal events, see the NY Times article HERE

What is Cereal?

Cereal is made from wheat, rice or corn - all of which are grains and almost entirely carbohydrate.

As you can see from the picture below. You're eating 23g carbs in less than two tablespoons of cereal, and one of those spoons is pure sugar. What's even more obscure is someone has allowed them to market the benefit of milk fortified with vitamin A & D as an added value (because you can't eat cereal without milk).

Imagine if all food manufacturers did that -"This fillet steak is a great source of protein and essential amino acids, but if you add kale you also have vitamin K, fibre, antioxidants, and calcium. Buy the steak!".

What about nutrition?

There is absolutely nothing else in cereal (other than what they add) which has any nutritional value.

The health consequences of regularly eating cereal can be serious. Research indicates that excessive amounts of processed grain and added sugar may result in hyperglycemia (high blood sugars), insulin resistance - type 2 diabetes, heart disease, and cancer.

What about oats?

Many people fly the flag of oats - They certainly do contain antioxidants, fibre, vitamins and minerals which are beneficial to our overall health. There is research showing they can help us lower LDL (bad) cholesterol, and if you are eating the 'lesser' processed variety, they're also low in sugar.

However, you will see claims that they lower your blood glucose levels. This is dubious at best considering in 100 grams of oats there are 66 grams of carbohydrates, and 85% of those carbs are starch. You may see a slower blood sugar rise (due to the fat and fibre content) than other processed carbs but it will still be a considerable rise, to say the least.

Often, we may also accompany oats with fruit to make it more palatable, and this will simply add a short spike in blood sugars to add to the oats long rise. So, next time someone tells you oats are a 'flawless food', tell them to check their blood sugars 2 hours after eating them.


The following are things to bear in mind about breakfast:

a) If you suffer from the 'dawn phenomenon' or 'feet on the floor syndrome', having a high carbohydrate breakfast is not recommended due to the industrial quantities of insulin required. Having eggs or another protein is more suitable as the insulin response is far less and protein is much more satiating, keeping you fuller for longer.

b) Breakfast is optional. There is no scientific evidence to back up any claims that breakfast is an important meal. If you don't wake up hungry, don't eat.

c) Insulin resistance is at its highest in the morning due to the release of overnight growth hormones like glucagon, epinephrine, and cortisol. Having cereal for breakfast means injecting large quantities of insulin and increasing your risk of hyper or hypo-glycemia before you even get to work.

The Breakfast Myth

For a long time we have been told breakfast was the most important meal of the day, or 'eat like a king at breakfast, a prince at lunch and a pauper at dinner'. Doctors and dieticians echoed this and overtime this has become entrenched in our society.

There is zero evidence for this.

You're more at risk of spiking your blood sugars, get more hungry and earlier in the day, reaching for that croissant or muffin. You're also more likely to eat more calories over the whole day, and there is no significant metabolic difference between breakfast eaters and skippers, so the notion that you 'kick-start' your metabolism is a fallacy.

To see the latest research from the British Medical Journal (BMJ) on this myth click HERE

We're not cattle - so we need to stop food manufacturers from treating us like them.

We must ask ourselves; why are we eating this? We know it's full of sugar. We know that 91% of corn flakes is carbohydrate. We know that when it's marketed as 'wholegrain', it means that it resembled a grain once upon a time... but not now.

Grain is what we feed cattle and other livestock as it's inexpensive and energy dense. That means we want them fatter, so we feed them grain. Keep that in mind.

Highly refined cereal is carbohydrate and sugar dense, and will impact you or your child's blood sugars to such an extent that it will be very difficult to control.

In my humble opinion, cereal has no place on anyone's kitchen table - let alone a person with diabetes. Steel-cut or rolled oats are not overly good or bad but must be considered in moderation due to their impact on glucose levels.

Breakfast is to 'break your fast', how long that fast is, completely depends on you. But don't be fooled into thinking you need to be eating as soon as you wake up.

As with all aspects of diabetes, track your blood sugars and perform your own tests at breakfast. If you're not hungry and your insulin resistant when you wake, have a coffee and forget about food till lunch. It certainly won't do you any harm.


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Totes agree Great blog

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