Common wisdom has assumed that a woman’s metabolic rate naturally declines at about 3% to 5% per decade from about her 20’s. This perception has always been accepted as an explanation for why women tend to gain weight and lose muscle mass as they age. But it turns out that natural declines in metabolic rate are not necessarily the culprit until much later in life.
The term “metabolic rate” is not always well understood. It refers to the calories your body needs to function without gaining or losing weight. A basal metabolic rate (BMR) is the number of calories you need to consume for your body to perform essential life functions, such as breathing, digestion, and blood circulation. In other words, your BMR answers the question: how much energy does my body burn when I am at rest?
As we age, we assume that our bodies automatically burn a lot more energy in our 20s and 30s but slow down as we enter middle age and senior years. But it turns out that the truth is more nuanced. The fact is a person’s BMR peaks at around age one. After that, BMR declines about 3% annually until age 20. From 20 to 60, BMR is relatively stable. From age 60 on, BMR decreases at a rate of about 1% per year.
So what gives? If our basic energy consumption rate does not change, why do women experience a metabolic decline as they age? The answer may involve several factors.
What is Metabolism?
Before going further, it is essential to distinguish between metabolic rate and metabolism. Metabolic rate refers to the number of calories your body needs to function. Metabolism refers to the chemical processes that occur within your body to maintain life, such as breaking food down into energy, synthesizing proteins and other biomolecules, and eliminating waste products. Some people have a faster metabolism – that is, their body processes food faster – and others have a slower metabolism. But this is not the same as the metabolic rate.
Loss of Metabolic Rate in Women
As a recent study indicates, your BMR does not naturally decline as you age until you reach the age of 60. And yet, almost universally, women experience the same changes as they grow older, even before they reach 60: weight gain, loss of energy, and loss of muscle mass. If a natural decline in BMR does not account for this shift, what does?
Just because your BMR is constant, it does not mean that your metabolic rate – the rate at which you burn calories – always stays the same. The following factors account for the majority of women’s metabolic rate decline.
Loss of lean body mass: Generally, women have less muscle mass than men, and they naturally lose muscle mass as they age. Because muscle is more metabolically active than fat, a decrease in muscle mass lowers the metabolic rate. This can result in a downward spiral: a lower metabolic rate means fewer calories are being burned, which leads to weight gain, which leads to less exercise, which leads to loss of muscle mass, which leads to a lower metabolic rate, and so on.
Body and lifestyle changes: When you are young and your body is in a growth phase, your body produces human growth hormone. This hormone helps to burn calories. However, as women enter adulthood, they stop growing, and their bodies produce less human growth hormone. They also tend to become less physically active. They burn fewer calories overall than they used to when younger, yet often consume the same amount of calories. This combination of factors means that they will gain weight and lose lean muscle mass, leading to a decrease in metabolic rate.
Pregnancy: Gaining excess weight during pregnancy, particularly if not managed postpartum, can reduce muscle mass and a lower metabolic rate. Furthermore, inadequate sleep, common during and after pregnancy, can disrupt hormonal balance. Hormonal factors, particularly concerning the thyroid, can contribute significantly to changes in metabolic rate.
Menopause: The hormonal changes that occur during menopause can significantly affect a woman’s metabolic rate. Declining estrogen levels during menopause can increase abdominal fat, which contributes to a decrease in metabolic rate. Additionally, hormonal fluctuations during menopause can lead to insulin resistance, further affecting metabolic rate.
Hormonal imbalances: Hormonal changes may be the result of things like pregnancy and menopause, but other things can disrupt and impact the hormone system, as well. If you have a hormonal imbalance, it can cause changes not only in weight and energy levels but can also affect your mood, temperament, sleep patterns, skin condition, memory, ability to concentrate, and other things.
Addressing the Problem Naturally
There are several natural ways that women can address a decline in metabolic rate. One critical step is to make lifestyle changes, focusing on diet and exercise. Shifting to a protein-rich diet and engaging in an exercise regimen that includes weight-bearing exercises can naturally increase a woman’s metabolic rate. But lifestyle changes cannot always remedy a problem, especially if a hormonal imbalance is at the root.
At REVV Health, we know that feeling fatigued or experiencing a chronic health issue should not be explained away with the rationalization that “You’re just getting old,” “You need to exercise more,” or “Here, take this medication.” You know when something is not right when how you feel physically does not match how you know you ought to or want to feel.
Just because our bodies go through stages of decline as we age does not mean we cannot or should not take proactive steps to live our best lives, no matter our age. Hormonal problems can make you “feel” older and lead to serious health problems – including causing weight gain, fatigue, weakness, depression, and anxiety. These problems will lead to ever-worsening health overall, both short- and long-term. You don’t have to accept that.
If you want to do something about how you feel and regain control of your health, contact REVV Health today. With a blood test analysis focused specifically on your hormonal levels, we can tell you whether a hormonal imbalance may be at the root of your problems. Learn how to optimize your hormone levels to live the life you deserve.