What a period such as the Christmas holidays can show is just how easy it is to put on weight. Those who increased their physical activity over that period would have had the best chance of not gaining any.

So, from all the daunting array of weight loss pills and schemes, what is the best approach to lose those kilograms now that post holiday routines are back in place? The obvious answer is any scheme that results in fewer calories going into our mouths and more calories burnt through increased levels of physical activity - ie. a lifestyle based approach.

What goes in often surprises people when it is analysed and some need strict guidelines as to what to have. To make things easier there is an increasingly popular option of using meal replacements that are sometimes called VLCDs or very low calorie diets drinks that make up a whole meal.

Each 'milkshake like' drink contains about 130-150 kcal, including essential vitamins and nutrients. They also give a feeling of fullness that lasts until the next meal - some fruit can be used as a top up without significantly altering caloric intake.

For weight loss use at least two out of three meals but even using one a day instead of a meal can be helpful. Three can be used for quicker weight loss but only under medical or a dietitian's recommendation.

Brand names are Optifast and KicStart available from some pharmacies or through an internet pharmacy. Cost varies from about $2-3 per sachet for one meal so they are very affordable compared with other food. They come as a powder form that is mixed with water, skim milk or even low fat milk. Follow up with your GP is recommended to monitor weight, waist measurement, blood glucose, blood pressure, cholesterol etc as well as provide ongoing motivation for lifestyle change.