Recent studies have shown that, on average, adults gain 5 lbs (2 kg) in the four-week Christmas period, just by eating an extra 500 calories a day.
We would need to jog the equivalent of seven miles to burn off this number of calories.
Of course, this is not the best approach; regular exercise should go hand in hand with a healthy diet.
However we can afford a few indulgencies at Christmas, simply because one week later a fresh new year usually spurs us to get healthy once again.
Children need to be active for 60 minutes every day of the week.
A recent Public Health report showed that people who are physically active reduce the risk of developing major chronic diseases later in life.
Activities should be of moderate intensity to help develop and maintain a good level of muscular fitness and flexibility.
Studies show that active parents tend to have active children. And we know, as parents, that it is our responsibility to keep our children healthy.
So, naturally, we should lead by a good example and keep fit as a family. You can start by doing activities as a family by turning off the TV to get out your bikes, by visiting the local leisure centre to go for a family swim or to play football together.
Even though there is a sleigh load of activities that families can do to keep fit, walking is likely to be one of the easiest, most convenient and cheapest.
Walking has long been overlooked as an exercise activity that helps you lose weight and keep healthy.
You can use a motivational tool such as a pedometer to measure the number of steps you walk in a day. This pager- sized device, available from most pharmacies clips easily onto your waist and can be used by all family members. So why not hold a daily competition to see who has the highest recorded number of steps?
Your children can be encouraged to walk more, by allowing them to walk to school; to the shops; to the park after school to get some fresh air; and to the playing fields to support the local sportingheroes. This extra pavement pounding will contribute nicely towards your child's 60 minutes of exercise a day.
Once the festivities are well and truly over, it is tempting to throw caution to the wind and follow a faddy diet to see drastic results.
Instead, a wiser approach would be to introduce a sensible healthy eating plan to the family.
You can do this by getting rid of the leftover food from Christmas, especially those tins of chocolate and crisps that are oh-so tempting.
Replace this by increasing your intake of fruit and vegetables that are naturally low in energy and fat and high in fibre.
Statistics show that, on average, children eat only two of their recommended five portions of fruit and vegetables a day, so search for a variety of recipes that include these health-boosting food items.
Reduce your fat intake by avoiding fatty meats and meat products, and by choosing lean cuts of meat instead. Shockingly, 92 per cent of children eat too much saturated fat, so leave off the fried foods and go easy on the pastries, cakes, buns and biscuits.
Eat the same meals together as a family at the same time. This way, your children not only benefit from quality time with you, but are more likely to accept the food put in front of them, too.
The World Cancer Research Fund (WCRF) has launched the Great Grub Club website, which is the firstever website to aim the healthy lifestyle message at four to seven year olds, and is a response to warnings from health professionals about the worsening situation with childhood obesity.
Children can visit the Great Grub Club website at www.greatgrubclub.com.
Similarly, The British Heart Foundation has an area specifically for young people on their website. This is aimed to teach youngsters how to be Heart Smart by keeping active and eating the right foods. Have a look at www.bhf.org.uk/heart-health/children-and-young-people/childrens-resources
Health and Fitness for families – a complete well-being guide on one website. Find out your BMI, complete an online fitness assessment, plus take a psychological and aptitude test to find out what sport is best for you! Go to www.nhs.uk/livewell/fitness/Pages/Fitnesshome.aspx
Use the Body Mass Index to find out if you're a healthy weight for your height. Go to www.weightconcern.org.uk to calculate yours.
For more general information on diet and exercise for the whole family go to: www.nhs.uk/pages/home.aspx
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