A few weeks ago on a road trip after a weekend Dragonboat regatta in the country the only food available was a fast food chain. My friend looked guiltily at me and said “I guess you won’t be able to eat anything” as if the mere sight of fast food would cause me to go into some sort of fit requiring a dash to the nearest hospital. You’ll all be happy to know that I do eat fast food sometimes and survive to tell the tale!
Like a lot of dietitians I love to cook, but it’s not always possible to cook a meal at home and fast food is a convenient option. For a healhty diet it’s best to limit your visits to fast food places to once a week or less. Smart choices at the counter can also make a big difference. As of February this year people in New South Wales (the state in Australia where I live) will start to see more information that will help them make that choice. New laws have just been passed so that by February 2012 all large fast food chains will have to show the kilojoule content of all food on the menu. Those of you in many places around the world have had this for some time.
So what do the numbers mean?
The kilojoule (kJ) content of a meal is the amount of energy the food provides. Kilojoules are the metric equivalent of calories and one Calorie is equal to almost 4.2 kilojoules. It’s hard to know how many kilojoules are in a meal just by looking at it so lablelling a menu can help. For example a small hamburger is around 1000 kJ while the larger ones can be 3000kJ. A muffin can be anywhere from 500kj to 2000kJ.
The 2-7-2 Guide
When you're looking at the menu kilojoules on the menu, how do you make a choice? Try the 2-7-2 guide: 2,000kJ for each meal and 700kJ for each snack. This way 3 meals and 3 snacks roughly adds up to the average adult daily intake of 8700kJ. Remember this includes drinks like coffee, alcohol and soft drinks (soda).
So when you're standing at the counter making your order a good choice is one that will provide around 2,000kJ including the drink. Then you can enjoy your meal knowing you've made a healthier choice.
At this stage the labelling in NSW is only energy but it may soon also include fat and salt content as is the case in some places around the world. In this case choose foods lower in fat and salt if possible.
How much do you need?
We all need energy from food but how much you need everyday depends on individual differences including your age, gender, how active you are and your weight. So it makes sense that we might need more or less than the average 8700kJ. An active 30 year-old man would need more than his 70 year old gran who walks to the shops each day.
As a rough guide the kilojoule values below give a idea of the amount of energy you need each day. The lower values are for people that don’t get much exercise each day. The higher values are for people that work in very physical jobs or do sports training for many hours each day. If you get at least 30 minutes of exercise each day you are likely to fall somewhere in between these values.
Women under 60 years need between 8,000kJ and 10,000kJ
Women over 60 need between 6,000 and 9,000kJ
Men under 60 need between 10,000 and 15,000kJ
Men over 60 need between 8,000 and 12,500kJ
These values are just a guide. For a closer estimate of the kilojoules you need each day try this online tool or talk to an Accredited Practising Dietitian.
If you live in an area that has been labeling fast food menus for some time I’d love to hear about if it has changed the choices you make.