The first thing to say here is that a week might be a long time in politics but it certainly isn't in respect of weight loss. Pretty much everyone who has ever lost weight will have a week somewhere along their journey during which, for no apparent reason, they stayed the same or even gained, and there can be any number of causes that have nothing to do with the diet "no longer working".
The bottom line is that if you are giving your body less fuel than it needs, it has to dip into its fat stores to make up the shortfall, but sometimes this effect is masked by other processes in the body, chiefly those that result in water retention.
One of the more surprising ones is exercise. Many people who have been using diet alone to lose weight then take up a vigorous exercise regime to boost their losses find that initially the reverse will happen and that they experience a gain. This is due to the natural process of muscle repair which requires extra water to be retained in the body and is therefore a temporary effect that will even out given time and not something to be concerned about.
Other causes can include constipation, inadequate hydration and poor liver function, but for women it is even more complex due to the hormonal interplay of the monthly cycle.
Most women are aware of the issue of bloating during menses itself but it is perhaps not as well known that bloating can also occur as oestrogen rises during the middle of the cycle (ovulation). This might mean that your weight loss seems to grind to a halt not once but twice every month.
The good news is that as long as you stick to your regime, you will be burning fat in the background and eventually the water will depart giving you a nice loss, but it can certainly be frustrating in the meantime.
There can of course be underlying health issues that prevent or drastically slow down weight loss, and if you have reason to suspect that you may be suffering from one of them, you shouldn't hesitate to consult a medical practitioner, but in most cases when a previously successful regime fails to deliver on the weekly weigh-in day it's simply a question of understanding that your body has its own agenda when it comes to weight loss, regardless of what you might be expecting.
So be patient and consistent, and chances are that the scales will soon be your friend again.
David Bowie, owner of Healthy Fit Life, is a mobile personal trainer and sports massage therapist working in the Farnham and Camberley area.