3 steps to losing fat, not muscle, according to a dietitian

You’re probably making mistakes

Dietitian and nutritionist Susie Burrell shares with Body+Soul some of the biggest mistakes people make when embarking on a weight loss journey, and what to focus on instead.

While many of us are keen to lose weight, from a metabolic perspective, when we lose weight ideally, we will lose predominately body fat rather than waste away muscle mass. 

Indeed, strict calorie and carbohydrate restrictions will result in relatively quick weight losses on the scales, but in general, it is much more muscle mass that is lost, than fat under these conditions. 

This means if your ultimate goal is to lose body fat whilst preserving as much muscle mass as possible, you need to follow these 3 simple rules to help ensure you are ultimately not further harming your long-term metabolism.

#1. Don’t cut the carbs completely

As carbohydrates are the primary fuel for the muscles and the brain, reducing the total amount of carbohydrate you consume each day will result in some increases in fat metabolism initially, but over time, if your total carbohydrate intake is grossly inadequate for the amount of activity that you do, metabolism will slow to account for this effect perceived deficit and fat loss will slow over time.

This means that the average person will need to keep their overall carbohydrates at a minimum of 30 to 40 per cent of total energy intake, or at least 80-100g a day to prevent a reduction in metabolic rate over time. 

This means if you have been actively trying to drop a few kilos of body fat, but the scales refuse to budge, it may be worth checking your overall carbohydrate intake and ensuring it has not dropped below 80 to 100g a day, especially if you are exercising regularly.

Also keep in mind, that the more active you are, and the more weight you lose, the more you will likely need more carbohydrates to adequately fuel the muscle. So if you are finding yourself constantly hungry, or craving sweet foods, it may be a sign your carbohydrate intake is still too low.

Carbohydrates are the primary fuel for the muscles and the brain. Image: iStock

#2. Know the power of protein

It is impossible metabolically to solely lose body fat when the body is in a calorie deficit, and in this state, we will always also lose some muscle mass. One way to help minimise this effect is to keep a close eye on your overall protein intake. 

The average adult requires at least 1g of protein per kilo of body weight or roughly 60 to 80g a day. To build or even retain muscle mass, bumping this overall amount to 1.5 to 1.6g per kilo or upwards of 120 to 140g each day via five to six small meals that contain 20 to 30g protein per meal will help to minimise muscle mass losses when you are actively trying to lose body fat.

It may also be helpful to know that as muscle weighs more than fat mass, at times when you are trying to lose body fat, a drop in body measurements, especially around the waist, even if the scales do not shift significantly is suggestive of losses of body fat whilst still retaining muscle mass.

#3. Train your muscles

The final powerful step you can take to help minimise muscle mass loss when actively creating a calorie deficit that supports fat loss is to make sure you are including some resistance training on your exercise schedule. 

While cardio training will remain important to help burn a higher number of calories each week, including some resistance training each week will stimulate muscle cells and help to prevent muscle cell breakdown. 

This may translate into a weekly weights class, circuit-style workout or even lifting a few weeks at home - anything that places resistance on the body's major muscle groups.

Originally published as 3 steps to losing fat, not muscle, according to a dietitian