Wouldn't it be lovely if something simple could double the weight loss you've been working so hard for? The good news is that it can — and it isn't a pill, a fat-melting gadget or some extreme diet where you eat nothing but broccoli. The answer is refreshingly easy: start keeping a food diary.
According to research from the Kaiser Permanente Center for Health Research, writing down everything you eat each day is one of the most effective things you can do to lose weight — and it may as much as double your results.
A study published in the American Journal of Preventive Medicine found that keeping a food record helped prevent the little slips that derail a diet. The researchers put it plainly: the people who kept the most detailed food records lost the most weight — about twice as much as those who kept none. Why? Because when people write down what they eat, they naturally start choosing lower-calorie, lower-fat foods.
In the study, participants followed a heart-healthy, low-cholesterol eating pattern rich in vegetables and fruit (the DASH diet) and did at least 30 minutes of exercise a day, recording both their food and their activity properly and consistently. Roughly two-thirds of participants lost around 6 kg over about six months, and 1,700 participants lost at least 4 kg. Those who kept a daily food record lost twice as much as those who didn't.
There were health benefits beyond the scale, too: as people lost weight, elevated blood pressure and cholesterol moved back towards normal levels, lowering the risk of heart disease and stroke. Even a 2.5 kg drop in weight was associated with a meaningful fall in blood pressure.
The mechanism is simple and human. When you first start recording what you eat, you begin to notice your food. Then you start to recognise it — and as you do, you gradually swap high-fat, high-calorie choices for lighter, lower-calorie ones, often without even trying. Habits shift quietly in the background. So if you've ever doubted that you could lose weight through healthy, everyday eating rather than a punishing crash diet, keep a food diary for a few weeks — you may be surprised at what those few written lines a day can do.
Merve Tığlı, Dietitian