We have been told for some time that whole foods are better for us.
Not only are they generally cheaper, but nutritionally they are superior as they have not been subjected to processing which destroys many essential nutrients.
Now, we have some powerful new research to show we actually burn significantly more calories when we choose less processed varieties of our favourite foods.
A study published in November's Food & Nutrition Research Journal, completed an experiment that measured the amount of energy produced from a cheese sandwich made using dense wholegrain bread and cheddar cheese compared to a cheese sandwich made using processed white bread and processed sliced cheese.
The meals were matched for protein, carbohydrate and fat amounts and fed to healthy men and women. It was found that while the sandwiches were rated as equally as satisfying for the study participants, there were major differences in the postprandial thermogenic response or the number of calories required to burn off the sandwiches.
It was found that the wholefoods cheese sandwich meal resulted in burnt 137kJ (33 calories) or 19.9 pe cent of the total energy of the meal compared to only 73kJ (17 calories) or 10.7 per cent of the processed food meal — almost 50 per cent less.
As a one off meal this may not seem all that significant but over the course of a day this study would suggest that you can burn 500-600kJ extra per day, or 100-150 more calories simply by choosing wholefoods.
In the course of a week or a year these numbers add up and may explain why so many of us have a gradual 1-2kg weight gain each and every year.
While this is a one off study, it is a powerful reminder of the benefits associated with eating wholefoods whenever possible.
So when it comes to some of our favourite food choices, here are simple swaps to move towards whole food eating.
Pork, beef, turkey, chicken mince — they are cheaper alternatives to fillets of meat and chicken breast and very popular for families. But a meal of beef strips or chicken breast, even shredded, is going to be a much better choice for weight control.
There is no doubt that fresh fruit is very good for us but when we process fruit and turn it into dried fruit, juice or fruit straps and bars it will lose its natural burning effect that benefits from its fibre content.
Ham, shaved turkey, pastrami, luncheon meat — popular sandwich fillings but packed with salt and often fillers meaning they are digested much more quickly for fewer calories.
Bread and wraps
As a general rule of thumb, the denser and darker the bread, the higher the post-meal calorie burn will be.
Wraps are a relatively more processed options too and as such wholegrain, lower carb varieties will boost their burn factor.
Traditional varieties of yoghurt that are strained and pot set such as Swedish quark, Icelandic yoghurt and Greek yoghurts are much higher in protein and as such will require a much greater number of calories to digest.
If you prefer fruit yoghurt use a less processed natural yoghurt base and add some fresh whole fruit such as berries.
Many of us enjoy our potatoes mashed or made into chips but without doubt the best way to eat a potato is roasted, whole with the skin intact. Just go easy on the butter or sour cream.
100% nut spreads are exceptionally good for us but eating a handful of mixed whole nuts will boost your calorie burn.