Is all sugar bad in a healthy diet?

Someone asked me recently if all sugar was bad. And, unfortunately, the answer to this question isn't easy.


You see, when it comes to sugar, there are different types of sugar, such as glucose, fructose and sucrose. Your body breaks down starches and sugars from plants so that your body can use them for energy. Your brain and red blood cells only use glucose as energy. 

Sucrose is a combination of glucose and fructose and is found in fruits, vegetables, and plants. Sucrose is the compound extracted to create granulated sugar, aka table sugar or white sugar.

It is pretty apparent that eating sugar in processed foods such as sweets and fizzy drinks, cereals, yoghurts, sauces, and dried food is not good for your health. But what about fruits?

Fruits contain an abundance of antioxidants, which are vital in neutralising free radicals in your body that cause oxidative stress, but they also contain a lot of sugar. And, in contrast, high blood sugar actually contributes to oxidative stress. However, some fruits also contain fibre, which slows the rate of digestion and may lead to fewer blood sugar spikes.

You can use the glycaemic index to determine which fruits are less likely to cause blood sugar spikes. For example, cherries, grapefruits, plums, peaches and prunes all have a glycemic index under 30 due to their fibre content. You can read more about the glycaemic load in my article, Understanding the Glycaemic Index and low GI diets.

And then there are natural sugars such as maple syrup, honey, coconut sugar, agave, or molasses. But, as with table sugar, these contain glucose, sucrose and fructose, so even though they retain nutrients due to their natural form, they will still spike blood sugar if consumed on their own. 

As with most things, sugar becomes the most harmful when you consume too much of it over a long period.

Insulin is a hormone produced by the pancreas that helps keep your blood sugar in check. However, after a continued assault of extremely high blood sugar spikes - which may amount to as little as a bowl of sugary cereal every morning - your cells become desensitised to the effects of insulin, and you end up with higher blood sugar for the most part and bigger dips in energy when you crash. 

And then it comes down to you. If your cells are in tip-top condition, then perhaps you can regulate your blood sugar more effectively and don’t feel the effect of consuming sugar. However, if your cells are already in an environment where there is systemic inflammation, your energy processor (mitochondria) is dysfunctional, or the outer edge of your cells (the cell membrane) is damaged, you may not be able to handle much sugary food without it affecting how your feel, your energy and your autoimmune symptoms. 

Dysregulated blood sugar can contribute to autoimmune disease for many reasons, one being that high blood sugar can cause advanced glycation end products (AGEs). AGEs are proteins or fats, such as enzymes, cell membranes and DNA, that become glycated after exposure to sugars in the body. When this happens, their function is impaired, which causes oxidative stress and inflammation.

Both inflammation and poor circulation are linked to autoimmune disease, and studies suggest that AGEs play a major role in the development of atherosclerosis. 

So, is all sugar bad?

As is often the case, it depends. But in the obesogenic environment that we are all generally surrounded by, it is best to minimise your sugar intake as best as you can.

If you want to establish a healthier relationship with sugar, you can join the Sugar RESET challenge starting on 3rd October 2022. A seven-day challenge to help reduce sugar cravings, increase energy, and make you feel happier.

And if you would like to take steps to improve your health, you can book a free initial consultation with me via my Nutritionist Resource profile. 

The views expressed in this article are those of the author. All articles published on Nutritionist Resource are reviewed by our editorial team.

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London W1G & Harrogate HG1
Written by V. J. Hamilton, Autoimmune Disease Expert | BSc (Immunology), DipION, mBANT
London W1G & Harrogate HG1

Victoria is a qualified Nutritional Therapist and member of BANT, focusing on autoimmune disease including skin disorders, heart disease & neurological issues as well as gut health & fatigue. Victoria has a BSc in Biochemistry & Immunology which she uses in her practice, using only evidence-based nutritional therapies to support chronic conditions.

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