Sugar and energy: how to avoid afternoon crashes
A familiar feeling: after a sweet snack your energy shoots up and then drops sharply. We look at why this happens and how to eat so that your energy stays more even.
Fast carbohydrates and sugar give you an instant energy boost because glucose enters the bloodstream quickly. But blood sugar falls just as quickly — and you feel it as sudden tiredness, irritability and the urge to eat something sweet again.
Why does the energy "rollercoaster" happen?
The simpler and faster a carbohydrate is absorbed — a chocolate bar or juice on an empty stomach, for example — the sharper both the rise and the subsequent fall in blood sugar. Protein, fibre and fats slow this process down, making your energy steadier.
What can you do instead of cutting out sweets altogether?
- Combine sweet foods with protein or fibre — for example, a piece of fruit with a handful of nuts rather than on its own.
- Start the day with a filling breakfast that includes protein, not just toast or plain porridge.
- Do not leave long gaps between meals — being very hungry makes you more likely to overdo the sweets.
- Choose whole foods — vegetables, pulses, wholegrains — they provide slower, steadier energy.
Read more about how to put together a filling breakfast in "Healthy breakfast for energy", and find snack ideas for between meals in "Snacks for energy". For an extra lift during the day without sugar spikes, some people use Energy Enhancer or X39 — they contain no sugar and no caffeine.