Struggling to lose weight? You might be feeling that you’re doing everything right-eating less, moving more- but are just not getting the results you should. Could your metabolism be halting your progress? And if it is, what can you do to speed it up? Or is there something else at work. In this article we will look at 6 common metabolism myths and unwrap the facts.
What is metabolism?
What most people actually mean when they talk about metabolism in relation to weight is their ‘metabolic rate’- the amount of energy that the body uses each day. The biggest component of this is your basal metabolic rate (BMR), which is the amount of calories (energy) your body burns at rest. 60-80% of your daily energy is spent this way on functions like breathing, keeping your heart beating, your blood circulating and repairing cells. You spend your remaining daily energy on physical activity (10-30%), and about 10% on digesting food.
Body size and composition, age, gender and genetics can all affect BMR, and account for the variation in resting metabolic rate between different people. The amount of muscle you have is the biggest contributor to your BMR. This is one reason why men typically find it easier to lose or manage their weight than women.
Now we come to the 6 most common myths regarding metabolism.
Metabolism slows down at menopause
Possibly but this has more do to do with the age at which menopause occurs- around 51 on average in Australia- and the fact that menopause changes where fat is typically stored. Age-related weight gain is real, often due to loss of muscle mass, which ramps up after the age of 50.
Most people also reduce their physical activity levels as they age. Because muscle is hungry for fuel, the less you have, the less energy your body burns. The good news is that muscle loss can be slowed or avoided. Resistance training exercises such as yoga, Pilates or weights can help you retain or build muscle mass
Eating 5-6 smaller meals a day boosts metabolism
While eating regularly can help you avoid becoming overly hungry and overeating, meal frequency does not affect metabolism. One UK study found that regardless of whether people consumed their daily kilojoules across two or five meals, their metabolic rates remained the same, burning the same amount of energy over 24 hours.
People who are overweight have slower metabolisms
Actually, the opposite is true. People with larger bodies need more energy to carry out basic functions. Research shows that people who are overweight have faster metabolisms- or metabolic rates- than people who weigh less.
Foods and supplements can rev up your metabolism
Not for long, according to Dr Nick Fuller, a leading Sydney-based obesity researcher. “Certain ingredients, such as chilli or caffeine, might have a short term fleeting effect, but it doesn’t last and will have little effect on weight loss”
What about supplements? A US study reviewed the evidence around hundreds of supplements designed to promote weight loss, including ones that claimed to increase metabolism- and found that none of them delivered significant results.
A slow metabolism can make it harder to lose weight
Probably not. Having a slow metabolism is rare, usually due to an underactive thyroid. While a ‘faster’ metabolism means your body uses fuel more quickly, someone with a ‘fast’ metabolism can still gain weight if they consume more calories than their body needs. Research shows most of us underestimate just how much we eat and drink across the course of a week.
We are also good at overestimating how active we are throughout the day, and how much energy we burn when exercising. Weight control is part genetics, but also heavily influenced by our environment.
P.S. 1 in 20 Australians experience some form of thyroid dysfunction during their lives. An underactive thyroid slows metabolism and an overactive one speeds it up. Symptoms of an underactive thyroid are unusual weight gain linked with constipation, lethargy, or depression. Overactive thyroid symptoms include increased appetite and weight loss. If untreated, thyroid issues can lead to serious complications, so when in doubt, be sure to see your GP.
Eating more protein boosts metabolism
Not significantly. Protein takes longer for the body to burn, so it does have a higher ‘thermic effect’ than carbohydrates or fat, which means it increases our metabolic rate immediately after a meal. However, this effect, called thermogenesis, contributes only a tiny amount to the energy your body burns each day.
Many factors determine how many calories your body burns each day. Some you can’t change, like your genes, gender, how tall you are, and your age. What you can do something about includes your food choices, level of activity, and taking up resistance training to prevent muscle loss and to maintain your metabolism long term.
How do you support your metabolism & still lose weight?
Don’t use drastic measures like reducing calories to around 1000 calories or less a day. When this happens, your body thinks there’s a shortage of food and it responds by conserving energy, slowing your metabolism and weight loss efforts. And if your body does lose weight, it is also more likely to shed just as much muscle as fat.
My suggestion is to quit the crash diets and try these strategies instead!
1. Make small changes to your diet
Rather than attempting large changes that are difficult to maintain and leave you feeling like you’re depriving yourself, research shows that making small, healthy changes to your eating habits- and sticking with them- leads to long-term weight loss.
2. Put enough protein on your plate
Protein is necessary to maintain metabolism-friendly muscle mass. Try to make ¼ of your meal protein, accompanied by ¼ Low GI carbohydrates- and plenty of healthy vegetables of every colour.
3. Write what you bite
A 2019 study confirmed the value of keeping a food diary for weight loss. You don’t have to spend a lot of time filling it in each day for it to work, but you will get better results if you write down what you eat after every meal, rather than leave it all to memory at the end of the day.
4. Do some resistance exercise
This is essential to boost muscle mass. Muscle is often lost during weight loss, but muscle’s energy- hungry tissue helps to keep your BMR ticking along at a good rate. Although tweaking your diet will deliver better initial weight-loss results than exercise, regular aerobic exercise counts more when you are trying to keep the weight from returning.
5. Get a good night’s sleep
Research shows that a bad night’s sleep can make you feel hungrier. Sleep consistency- getting roughly the same number of hours sleep each night- can also influence weight loss.
A 2019 study found that people who got between 7 and 9 hours of sleep every night lost more weight than those whose sleep patterns were less consistent. This occurred even though both groups were following the same eating plan, and had the same overall amount of sleep.