RESEARCH NEWS

What’s more important for weight loss — calories or macronutrients?

It’s almost impossible these days to go a day without hearing about a new dieting fad or weight-loss trend. Most of that craze centres on slashing calories — an approach that works for many but leaves out a key aspect of nutrition: macronutrients.

According to Macquarie University’s Sport and Recreation team, rather than solely focusing on a calorie count, the macronutrient approach optimises your diet by determining the percentage of calories you should get from protein, carbohydrates and fat each day. Whether you are interested in cutting body fat or boosting muscle mass, macronutrient breakdowns can be catered to meet your goals.

What are macronutrients and why do they matter?

Carbohydrates, protein and fat make up our essential macronutrients. They provide the vast majority of our bodies energy in the form of calories, keeping us fueled throughout the day. One important aspect of the macronutrient approach is that it acknowledges not all calories are created equal: 100 calories of lollies and 100 calories of broccoli technically provide the same “energy” to your body but are processed very differently.

Think about eating 500 calories of ice cream and 500 calories of spinach; these two choices are reflected identically in the counting calories approach but contribute very differently within a macronutrient breakdown.

Metabolically speaking, foods high in protein and fibre keep us feeling full longer, leading to reduced calorie intake. Conversely, foods with high glycemic indexes, such as white bread and cookies, spike our blood sugar for a short time, providing quick energy but leaving us with a ‘sugar crash’ soon after. The speed that carbohydrates hit our system affects subsequent overeating and weight gain. This means it’s much more valuable to choose whole grain carbohydrates that are slowly digested (and often contain fibre) rather than processed grains.

The case for focusing on macronutrients

So, calories don’t tell the entire weight-loss story, but it’s important to remember that you can’t have macronutrients without calories. Each gram of fat provides nine calories, while protein and carbohydrates provide four calories per gram. Remember that you’re not eating macronutrients just for calories because every macronutrient has a purpose:

• Fats work to slow digestion, provide essential fat-soluble vitamins and have protective anti-inflammatory properties (omega-3s).
• Protein provides the building blocks for muscle and cell tissue, while also satisfying hunger and improving satiety.
• Carbohydrates provide a quickly accessible form of energy and fibre, which can leave you feeling full longer and slow the absorption of other nutrients (like sugar).

Depending on your age, weight and activity level, your body requires a certain amount of calories to maintain its weight. A diet that is 30 per cent protein might be great for someone on a 1200 calorie diet (90g protein) — but not so great for an athlete on a 4000 calorie diet. The solution? Take the time and invest in a consultation with your local dietitian to understand exactly what is right for you.

Focusing on macros promotes a more balanced diet by forcing us to take a hard look at the foods we are eating. The bottom line is to view your diet from a broader perspective that considers the nutritional benefits of different options and not only their calorie count.

The Macquarie University Sport and Recreation team recommend you seek medical advice before beginning any exercise or diet program.