March 2021

Energy and Fatigue After Surgery

After Weight Loss Surgery, it's completely normal to experience some fatigue and low energy. Your body is healing, absorbing nutrients differently, and adapting to significant change, all of which takes energy in itself.

The good news is that with the right approach across nutrition, movement and lifestyle, most people find their energy steadily improves. Here are five of the most common contributors to post-WLS fatigue, and what you can do about each one.

1. Not Meeting Your Protein and Carbohydrate Needs

Protein is the most important macronutrient after WLS. Your daily target is typically 60–80g for women and 80–100g for men, and falling short has real consequences for energy, strength and general wellbeing.

Aim for at least 25g of protein at every main meal, with 10–15g at snacks, to work toward your daily target. Consistent protein intake supports the body's essential functions, including energy production and general metabolic health.

Carbohydrates are your brain's preferred fuel source, so cutting them out entirely can leave you feeling flat, foggy and irritable. The key is choosing the right kind. Slow-burning carbohydrates like sweet potato, brown rice, oats and rye sourdough provide steady, sustained energy. Refined options like white bread and pasta are digested quickly, leading to energy spikes followed by a mid-afternoon slump, and increased hunger later in the day.

Make sure each meal includes a moderate serve of quality, slow-burning carbohydrates alongside your protein.

2. Nutritional Deficiencies and Malabsorption

After gastric sleeve and bypass surgery, a range of nutrients are less efficiently absorbed, including B12, iron, magnesium, B6, folate and others. These nutrients play important roles in the body's energy-producing processes, and gaps can show up as persistent tiredness, weakness or poor recovery.

Eating a wide variety of colourful whole foods is a great starting point, different coloured fruits and vegetables bring different nutritional benefits, so variety matters. But given the malabsorptive nature of many WLS procedures, food alone is often not enough.

Speak with your dietitian about regular blood monitoring to identify any deficiencies early, and discuss whether targeted supplementation is appropriate for your individual needs.

3. Not Moving Enough

When energy is low, exercise is often the first thing dropped from the daily routine. But regular movement is actually one of the most effective tools for improving energy and vitality, even when it feels counterintuitive.

Start small. A 20-minute walk each day is a completely achievable starting point, and you can build from there. Working toward 10,000 steps daily has well-documented benefits for overall health, energy levels and general wellbeing, and the effects compound over time with consistency.

Even light, regular activity helps reduce stress, supports better sleep, and contributes to a greater sense of vitality throughout the day. Choose movement you enjoy, and focus on building consistency rather than intensity.