Intermittent fasting: the basics

4 min read

Intermittent fasting means cycling between periods of eating and not eating, rather than changing what you eat. Common approaches include time-restricted eating like 16:8 (eating within an 8-hour window, such as noon to 8pm) and 5:2 (eating normally five days a week and much less on two). It's one way some people manage appetite and calories — not a magic fix, and not better than simply eating well for everyone.

If you try it, the aim is nourishment, not restriction. In your eating window, still build balanced meals with protein, fibre, vegetables and enough total food — skipping meals only to then under-eat, or to 'earn' food, isn't healthy. Drink plenty of water (you can have tea or black coffee during the fast), and choose a window that fits your life, your sleep and any medication times.

Start gently — for example a 12-hour overnight fast — and see how you feel. Some people find it helps them feel in control and snack less late at night; others feel tired, irritable, headachy or preoccupied with food, in which case it simply isn't the right approach for them. How you feel matters more than following a rule.

Intermittent fasting is not suitable for everyone. Please don't fast — and speak to your doctor first — if you are pregnant or breastfeeding, under 18 and still growing, underweight, have diabetes or take medication that must be timed with food, or have any history of disordered eating or a difficult relationship with food. For those situations, regular, balanced meals are the safer choice.

This is general wellbeing information, not medical advice. If you're considering intermittent fasting and have any health condition, take medication, or are unsure whether it's right for you, talk to your doctor or a registered dietitian first.