Do you have that friend who uses the excuse of, “I have a slow metabolism so it’s hard for me to lose weight?”
You think this is roll-your-eyes material or is there some truth in that statement?
What is your metabolism?
Well, simply put – it’s how your body uses energy to do all the stuff you need to live – breath, digest, circulate blood, and importantly, build and repair your body. Your metabolism is typically measured in kilojoules (kj) and there are loads of factors that can influence your metabolism, which we will explore later, but here’s the bad news. If we eat and drink more kilojoules than we need for our metabolism and exercise, we store it as fat.
But you knew that right?
Step in… Metabolic Rate
Different to metabolism, according to WebMD it’s “the rate at which you burn calories while your body is at rest” and measured as your “basal metabolic rate” (BMR). It may surprise you that just ‘living’ and ensuring our bodily processes are functioning, accounts for 50-80% of your daily energy use! Other impacts on our BMR are exercise of course and the food you eat.
Referred to as the ‘Thermic effect’; your BMR rises after you have eaten because you need energy to digest and metabolise the food you eat. According to Better Health, it can range between 2 percent and 30 percent depending on what you are eating and the size of the meal.
Fats by 0-5%
Carbs by 5-10%
Proteins by 20-30% (it takes more energy to process high protein – makes sense because food high in protein keeps you feeling fuller for longer!)
Specific foods include oats, almonds, yoghurt and salmon as well as hot and spicy foods containing chilli or mustards! Oh and don’t forget the good old caffeine (used in a lot of diet supplements) a stimulant that gives your BMR a slight increase (slight, as in probably not enough to help you lose weight).
Other factors that affect your metabolism
- Body composition. Sorry ladies, but if you need any more reason to get into weight training, this is it – men tend to have a higher BMR because women have a higher proportion of fat compared to lean muscle. Strength training to build those muscles = less fat = loss of weight = higher metabolic rate!
- Energy used during physical activity – 45mins per day of moderate intensity exercise can account for 20% of daily energy use.
- Genes – we all have one of those friends – it doesn’t matter how much they eat, they stay thin.
- Age – yep, metabolism slows down as we get older.
- Diet and Exercise – energy in vs. energy out.
- Thyroid – this regulates your metabolism by producing hormones that influence how your body performs. Disorders do occur where they may be underactive, leading to weight gain or in the reverse ‘overactive’ leading to weight loss.
- Dieting – if you cut down too much on your calorie intake you can slow down your metabolic rate, cleverly, to conserve energy.
- Temperature – who would have thought? Your body wants to maintain temperature so in the really cold or warm weather, your BMR will speed up to maintain body temperature.
So for your friend, you can let them know that research would say that while metabolism influences your body’s basic energy needs, it’s really your food and drink intake, as well as physical activity that will determine how much you weigh, and impact your weight loss goals.
Have you ever checked your metabolic rate out? Go to a personal trainer or health expert and ask them to calculate it for you.