Japanese dieters and those concerned for medical reasons about what they eat now have support and guidance in their pockets in the shape of a mobile phone calorie-counting service.

The trial combines two of the modern world's obsessions - phones and weight loss - to offer help to anyone who needs to know the nutritional value of what they're eating. It's being run by various public health bodies and Asahi Kasei , a Tokyo chemical and medical equipment maker,

Snack shot

Users simply use their phones to take a photograph of each meal and email it to the system. Real-life nutritionists will analyse their diet and give appropriate advice. It costs ¥4,500 (£19) to sign up to participate and then a further ¥2,500 (£10.50) each month.

Although it takes three days for each set of photos to be analysed, institutions using such systems, such as Hirakata Hospital in Osaka, see benefits in that a photo is more precise than keeping a meal diary.

A Hirakata doctor confirms that human weakness is really the bottom line. "Patients used to fill out meal logs, but people tend to forget things or underestimate their portions. Photographing meals and emailing them in is easier and gets more accurate results."