Nutrition, Gut Health & Fatigue: What You Eat Could Be Draining Your Energy

By Maryke Gallagher, Lead Nutritionist at Expand Health

Fatigue is complex and multifactorial, but many of its root causes are tied, directly or indirectly, to nutrition. From nutrient deficiencies and inflammation to gut imbalances and poor mitochondrial function, your diet plays a central role in your energy levels.

Nutrients and Energy Production

The body relies on macro- and micronutrients to power crucial functions like oxygen transport, enzymatic reactions, DNA repair, immune balance and mitochondrial energy production. When your diet is lacking, or when stress, illness or poor absorption interfere, your cells can't produce enough energy to keep you going.

Some common nutrients and their link to fatigue

• Iron deficiency: Required for oxygen transport and energy production.
• Vitamin B12 & folate: Important for making red blood cells, DNA repair and activation of enzymatic processes for energy production.
• Vitamin D: Plays a key role in mitochondrial function, has anti-inflammatory and immune modulating effects, involved in mood regulation and depression management. Often low in individuals suffering from chronic fatigue.
• Magnesium: Involved in >300 enzymatic reactions including ATP production (the primary energy currency of cells)

Women, vegetarians, athletes, individuals with gut issues or chronic illness, and those on restrictive diets or recovering from gastrointestinal surgery are most at risk of deficiency. Genetics can also influence how well your body absorbs or utilises these nutrients. Understanding your unique genetic profile can assist in getting to the root cause of your chronic fatigue.

Gut Health, Inflammation & Fatigue

There's growing evidence linking gut microbiome imbalances (dysbiosis) to chronic fatigue. A disrupted gut ecosystem can lead to systemic inflammation, compromised energy metabolism, and even neurocognitive symptoms or mood changes through the gut-brain-mitochondria axis, all of which increase fatigue.

What's going wrong?

• Reduced microbial diversity: Fewer beneficial strains mean reduced short-chain fatty acids like butyrate, which are vital for energy production.
• Leaky gut: Dysbiosis can also promote gut permeability that can trigger immune activation and inflammation. The production of inflammatory cytokines (proteins released by immune cells that cause inflammation) could contribute to fatigue by affecting motivation, serotonin levels and sleep. As chronic inflammation increases, it damages mitochondrial membranes and enzymes and reduces the production of ATP.

How to Nourish for Energy

To support both gut and mitochondrial health, prioritise:

• A plant-rich, anti-inflammatory diet rich in prebiotic fibres, deep coloured fruit, vegetables and plants that contain polyphenols such as flavonoids (tea, berries), curcumin (turmeric), resveratrol (grapes) and flavan-3-ols (cocoa), and other anti-inflammatory nutrients such as omega 3 and vitamin D
• Foods with natural prebiotics and probiotics (e.g. berries, oats, fermented foods, if tolerated). Probiotics play an important role in gut health by improving the gut barrier, supporting the production of short-chain fatty acids and ensuring a balance between favourable and less favourable microorganisms in your digestive tract.
• Nutrients like CoQ10, alpha-lipoic acid, L-carnitine, and magnesium

Note: While fermented foods are generally associated with positive gut health outcomes, they are not universally beneficial for everyone. Those with histamine intolerance, SIBO, or certain immune conditions may experience worsened symptoms and should use fermented foods cautiously.

Blood Sugar and Fatigue

Reactive hypoglycaemia, a sharp drop in blood sugar, can leave you feeling weak, dizzy and fatigued. It's often linked to insulin resistance, adrenal dysfunction, or high-carb meals without enough protein or fibre.

To support blood sugar balance:

• Eat structured meals (meal timing) with protein, fibre and healthy fats.
• Choose low-GI carbs (e.g. sweet potatoes, quinoa, oats).
• Optimise your intake of magnesium, B-complex vitamins, inositol, and vitamin D.
• Prioritise stress management and sleep.
• A healthy gut microbiome also plays a role in glucose regulation and insulin levels, lowering inflammation too.

Your Path to More Energy

There's no single fix for fatigue. If you're feeling persistently tired, it's worth exploring whether nutritional and lifestyle factors are at play. At Expand Health, our team can help you uncover the root cause and develop a personalised, sustainable plan to support your energy, mood and vitality.