Combat tiredness with antioxidant-rich foods

For years I struggled with fatigue and tiredness. As I had been diagnosed with several autoimmune diseases as a child and teenager, whenever I felt below par, I would put it down to ‘inflammation’ or just the way it was for me. 


I recall trying to stay awake after lunch at work, which was a task in and of itself, let alone focusing on work. And then there were the dizzy spells, headaches and blurred vision. 

At this point, I hadn’t drawn the link between the food I was eating and my symptoms. Still, when I was diagnosed with chronic fatigue syndrome in my early 30s, I started to explore more about the underlying root cause of my symptoms. 

I realised that my tiredness was partly due to dysregulated blood sugar and when I started to eat foods which helped keep my blood sugar in balance I had so much more energy. 

In this article, I will explain why imbalanced blood sugar can cause tiredness and fatigue and how you can improve your symptoms by eating a diet rich in antioxidants. 

Why does blood sugar dysregulation lead to tiredness?

When I work with clients struggling with fatigue, one of the first things we work on is blood sugar regulation, which is because when your blood sugar is out of sync, you are less able to produce energy at the cellular level, which leads to fatigue. 

On top of that, when your cells become desensitised to the hormone insulin, which is essential for blood sugar regulation, your blood sugar begins to rise more when you eat sugary or starchy foods and crashes a couple of hours later when your cells are finally able to respond to the excess sugar in your bloodstream. 

It is a vicious cycle, as once your cells become desensitised to insulin, also known as insulin resistance, you have less capacity to tolerate sugary foods, which means that even a tiny amount of sugar in your diet can lead to a crash. 

When I had chronic fatigue syndrome, my tolerance to sugar and refined carbohydrates was at an all-time low, and I knew every time I ate them, I would be on the floor a couple of hours later!

What causes insulin resistance?

In metabolic syndrome, including type 2 diabetes, one of the fundamental problems is oxidative stress. Oxidative stress is a state in the body when there are more free radicals than antioxidants which can cause damage to the cells and peripheral tissues. 

Your cells are neatly designed so their cell membranes can respond to ‘messages’ from hormones such as insulin. Insulin ordinarily will help increase the amount of sugar from the blood carried into the cell. Still, in a state of oxidative stress, this is significantly impacted, and as such less sugar is taken into the cell, which can lead to imbalances in blood sugar. 

If you continue to eat more sugar, this adds fuel to the fire, as the mitochondria, which are the cell's powerhouse, become hyperactive in a sugar-rich environment. In this state, they produce even more free radicals, causing further damage to the cell membranes and increasing insulin resistance. 

So how can you improve your blood sugar balance?

The first step in improving blood sugar balance is to remove sugary and highly refined carbohydrates from your diet. As a result, your cells will become more sensitised to insulin over time as oxidative stress improves and the cell membranes become more responsive to insulin. 

And when your cells start to utilise glucose properly again, you will feel more energised and less tired. 

In addition, another way to improve insulin sensitivity is to include more antioxidants in your diet which will help neutralise the effect of any free radicals and improve cellular function. 

Many studies have shown that natural antioxidants help to improve insulin resistance, especially in people with obesity or type 2 diabetes. 

Here is a list of powerful antioxidants which have been shown to help with blood sugar regulation, decrease oxidative stress and improve energy levels:

Vitamin C

There have been many studies on vitamin C's antioxidant abilities, particularly for cardiovascular disease, which may be due to its effects on oxidative stress and insulin sensitivity at the cellular. 

Eating an abundance of vitamin C-rich foods may help to improve insulin resistance. Here are some of my favourite vitamin C-rich foods which you can include in your diet:

  • broccoli 
  • brussel sprouts 
  • grapefruit 
  • lemon 
  • red peppers
  • kiwi
  • strawberries
  • tomatoes
  • cauliflower


Polyphenols, such as anthocyanin, have been shown to improve metabolic function and blood sugar balance in diabetic patients. Anthocyanins are found in red and purple fruits and vegetables such as berries, grapes and purple-sprouting broccoli. 

Other polyphenols include cinnamon and green tea, which contains a catechin called epigallocatechin-3-gallate (EGCG), both of which have been shown to stabilise blood sugar, with matcha powder having some of the highest levels of antioxidants.

Incorporating polyphenol-rich teas and foods in your diet may help improve your blood sugar regulation, such as green tea, cinnamon and hibiscus tea which is a rich source of anthocyanins.  

Cinnamon may help lower blood sugar levels by increasing insulin sensitivity, making insulin more efficient at moving sugar into cells. I often recommend cinnamon tea after eating, which helps to avoid blood sugar spikes and, most importantly, the subsequent crash after meals. 

Vitamin E

Vitamin E-rich foods include almonds, sunflower seeds, asparagus and avocado, and studies suggest help lower oxidative stress and inflammation, which may help with insulin resistance. 

As such, eating a diet rich in vitamin E-rich foods may help to improve energy levels and tiredness similar to those mentioned above. 

Alpha lipoic acid

And lastly, you can’t forget about alpha lipoic acid when it comes to improving insulin resistance and blood sugar levels. 

Alpha lipoic acid is a naturally occurring compound with potent antioxidant activity and has a cascading effect on the body as it switches on certain antioxidants genes which snowball its impact driving down inflammation and oxidative stress, which in turn improves blood sugar regulation and energy levels. 

Organ meat is a wealthy source of alpha lipoic acid, and many of my clients who start to incorporate organ meat into their diet see a significant improvement in their energy levels quickly. Antioxidants aren’t just found in plant foods, you can find them in organic meat and fish as well. But remember, when it comes to meat and fish, go for quality over quantity. 

Tiredness and fatigue can be debilitating symptoms to live with daily, but by lowering oxidative stress and inflammation and stabilising blood sugar levels with antioxidants, you can improve the way your body utilises energy so you feel more vibrant than ever. 

And if you would like to improve your relationship with sugar, find ways to be free of sugar cravings and have some go-to strategies to help keep your blood sugar in check, then why not join the 10-day Sugar RESET challenge on 22 February 2023? 

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

After 25 years of suffering from multiple autoimmune conditions that affected her energy, skin
& hair, VJ discovered she could uncover the root cause of her issues to transform her health & live without symptoms.

VJ now uses these same principles to help women with autoimmune disease regain their strength & live a whole and symptom-free life.

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