1200 isn't your number.

Because that figure is a legacy number rather than a personal one, and for a great many adults it sits well below what their body actually runs on — particularly taller people, men, and anyone physically active. A target set too low produces muscle loss, nutrient shortfalls, constant hunger and a rebound. The intake figure depends on things nothing here can assess, so the guide shows you how a real one is arrived at and who's qualified to set it.

A registered dietitian is the profession specifically qualified to do it, and a GP can advise and refer — some health services and workplaces offer this at no cost. The method is an estimate from your body weight, height, age, sex and activity, then adjusted based on what actually happens over several weeks. That adjustment step is the part internet plans leave out, and it's the part that makes the number yours.

Partly through structure: protein at every meal, vegetables taking the largest area of the plate, and foods with volume and water content, which is why two meals of identical calories can leave you completely differently satisfied. But partly by not setting the number too low in the first place — being hungry all day generally means the target is wrong rather than that you need more resolve. Sleep matters too, since short sleep reliably increases appetite the next day.

No — plans requiring that fail reliably and predictably, because eventually the plan gets abandoned in order to have the thing. Fitting it in regularly works far better than banning it. The same applies to cooking separately from your household, which is a common reason plans collapse: adjusting proportions of a shared meal beats making two dinners.

During pregnancy or breastfeeding, for under-18s without clinical supervision, and alongside insulin or certain diabetes medications, where reducing intake without adjusting doses can cause dangerously low blood sugar. And if counting has been distressing before, or there's a history with food you'd rather not go into, a calorie-focused plan is the wrong tool and can make things worse — support exists for that, and it's worth reaching out before rather than after.