It's time to stop counting calories, says leading nutritional biochemist and bestselling author Dr Libby Weaver. To control weight, count nutrients instead.
In her latest book The Calorie Fallacy, Dr Libby argues that the calorie equation used to measure our energy needs is completely outdated. "The concept that so long as you eat fewer calories than you burn, you will lose weight, is well overdue for an update."
That's because the calorie equation doesn't factor in the influence that today's foods and lifestyle are having on our metabolism.
"The Harris-Benedict Equation was first published in 1918 - the world was a very different place back then," she says.
"If your waistline is increasing, it's nothing to do with your calorie intake, but everything to do with the quality and wholeness of the foods you're eating."
'Real food', she explains, can be easily processed and utilised by the body, which means, for the most part, your metabolism works as expected and calories are burnt as they should be.
Processed foods and packaged foods, on the other hand - even low-calorie ones - can interfere with the body's usual mechanisms for digesting and burning food - a sure-fire road to poor health and potential weight gain that has little to do with calories.
"We've moved far too much away from the way food comes in nature. Our body is fully equipped to be able to break down real food. But we can't guarantee that it has the equipment inside of it to break down potentially artificial substances found in many processed foods."
THE TOXICITY FACTOR
Processed foods made up of concentrated forms of carbohydrates, additives and preservatives that keep them 'fresh' for weeks or months, contain what Dr Libby calls 'problematic substances'.
These substances are shunted to the liver and kidneys for detoxification and eventual excretion. But when the load arriving at the front door of either of these organs is too much for it to deal with at the time (due to the previous loads that are still being processed), the load gets moved to the fatty tissues of the body and the fat cells become storage houses for toxins.
It can get to the point where fat starts to take up residence in the liver - where a functioning liver cell once was - meaning detoxification is compromised and people gain weight, whether their calorie equation has changed or not.
Dr Libby says this is just one of the reasons it's hard to shift weight, despite cutting back on calories.
THE INSULIN FACTOR
"I think another big factor is insulin, released in response to rising glucose levels" she says.
The more glucose in our blood, the more insulin is produced in order to shift it. And thanks to diets high in carbohydrates and caffeine - plus an increase in adrenalin and stress - insulin levels are rising.
"It is big surges of insulin on and off over the day, or constantly high-circulating insulin, that are problems when it comes to fat-burning and the utilisation of calories," she says.
Insulin takes glucose out of the blood to the muscles where it's stored as glycogen for fuel later. Where there's too much glucose however, insulin takes it to the fat cells, which can continually expand.
The other problem with insulin is that when it's elevated, the body becomes deaf to the appetite-regulating message of leptin. "When you have high-circulating levels of insulin, you can't hear the message that the body's full," says Dr Libby.
"If you have spent months committed to exercising and eating well with little or no reward, have your blood glucose level and your blood insulin level tested," she advises.
EAT 'REAL FOOD'
The Calorie Fallacy covers a whole host of factors influencing the metabolic consequences of the calories we eat today, including the role of gut bacteria and the effect of stress on our metabolism.
Dr Libby says the most common response she's had to her book is 'relief'. "Because countless people say they've made countless commitments to their health... sometimes they've been rewarded and sometimes they haven't and they don't know why."
While offering several alternatives to counting calories, Dr Libby says increasing your nutrient intake is key. You'll not only improve digestion, but also assist the work of your liver, kidneys and all the other mechanisms involved in metabolism.
"The cells of the body don't live forever. They are always in a cycle of replication, repair and death," she says. "The health of the next generation of cells is dependent on the information they pick up on in their environment. And what's in their environment? Either nutrients or a lack of nutrients, one nutrient or many."
Some people, she says, are effectively becoming more and more toxic due to their lifestyle choices.
Turning this around might be easier than you think though. You can eat more nutritiously simply by replacing one meal or snack a week, from something packaged to something closer to nature.
"We essentially eat 35 times a week - 3 main meals and 2 snacks a day. Let's say right now you're eating 7 out of 35 meals that include real food. If you include just one more real food meal or snack every week, then in two months time you'll be at 14 out of 35. That alone would've literally doubled the amount of nutrients going into your body," says Dr Libby.
"For some people that's just game-changing, but it's also quite sustainable - a gentle step in the right direction."
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