Why We Gain Weight as We Age: Metabolic Changes

Comprehending Age-Related Weight Gain

A widespread issue that impacts millions of people globally is obesity. It is now a serious health issue. Numerous factors, including diet, inactivity, stress, medications, and genetics, are significant contributors to gaining and maintaining excess weight.

However, the prevalence of obesity among people has increased due to the neglected cause of aging. People are more vulnerable to a variety of chronic illnesses as they age. Obesity raises a person’s risk for serious diseases, which can occasionally be fatal.

Metabolism: What is it?

Metabolism converts the calories in food and drink into energy through chemical reactions. This process supports blood circulation, temperature regulation, and other vital bodily functions. Even when you’re sleeping, it continues to do this.

There are three primary ways that your body burns energy:

• The number of calories you burn while at rest is known as your basal metabolic rate, or BMR (also known as your resting metabolic rate, or RMR). Surprisingly, the majority of the energy you expend each day comes from this. (To get a good estimate of your BMR, use an online calculator.)
• The energy required for food digestion is called dietary thermogenesis.
• Exercise, ranging from cooking to running a marathon
• Maintaining a healthy weight is largely dependent on how many calories you consume compared to how many you burn, even though it is acknowledged that obesity is a complicated and chronic disease state rather than just a simple math problem. To put it briefly, in order to effectively lose weight, you must burn more calories than you take in.

Metabolic mechanisms

Here’s a closer look at how metabolism functions. Catabolism and anabolism are the two primary processes that make up metabolism in general.

The breakdown of macronutrients (protein, carbohydrates, and dietary fats) into their simpler forms is known as catabolism. For instance, your body converts carbs into glucose, which is then released into your blood as blood glucose (sugar). Additionally, your body stores glucose as glycogen, mostly in your liver and muscles. Your body uses these macronutrients as fuel for all of its cells.

Catabolism is the opposite of anabolism. Your body assembles smaller components, such as amino acids, to form larger structures, such as proteins. When your body needs to heal from an injury, anabolism is crucial. Additionally, it is necessary for the development of muscles and bones.

Changes in body shape with age

Your body naturally changes in shape as you age. Some of these changes are unavoidable, but your lifestyle choices can either accelerate or slow the process.

Fat tissue, lean tissue (muscles and organs), bones, and water make up the human body. People typically lose lean tissue after the age of thirty. Your muscles, liver, kidneys, and other organs may lose some of their cells. Atrophy is the term for this process of muscle loss. A condition known as osteopenia in the early stages and osteoporosis in the later stages may result from bones losing some of their minerals and becoming less dense. Your body contains less water as a result of tissue loss.

The spine’s gel-like disks between the vertebrae dry out and become flattened. The distances between the vertebrae are shortened as a result.
A more slumped posture may result from a loss of muscle and core strength.
As we age, our feet tend to flatten.

Microfractures in the spine with reduced vertebral height can be caused by osteoporosis.
After the age of forty, people usually lose one centimeter, or nearly half an inch, every ten years. After age 70, height loss occurs even more quickly. As you get older, your height may decrease by one to three inches (2.5 to 7.5 centimeters). Maintaining an active lifestyle, preventing and treating bone loss, and eating a healthy diet can all help reduce the loss of height.

It may be more difficult to move around with smaller leg muscles and stiffer joints. Your balance may be impacted by changes in body shape and excess body fat. These physical alterations may increase the risk of falls.

Men and women experience different changes in their overall body weight. Men typically start to lose weight later in life, after gaining weight up until the age of 55. A decrease in the male sex hormone testosterone could be connected to this. Up until the age of 65, women typically gain weight before starting to lose it. Later in life, lean muscle tissue is replaced by fat, which weighs less than muscle, which contributes to weight loss. Over a person’s life, weight changes can be significantly influenced by diet and exercise habits. Your lifestyle choices affect how quickly you age.

The following are some actions you can take to lessen body changes caused by aging:

• Exercise regularly.
• Consume a diet rich in fruits, vegetables, whole grains, and the proper proportions of healthy fats.
• Don’t drink too much alcohol.
• Avoid illegal drugs and tobacco products.

How does aging affect your metabolism?

It has long been believed that midlife BMR declines, making weight loss more difficult. You may have heard that women’s slower metabolisms make it more difficult for them to lose excess weight.

In middle age, metabolism slows down. According to data from over 6,000 individuals, metabolism stays constant between the ages of 20 and 60. Over the course of a lifetime, metabolism does alter, but only during these times:

• The highest metabolic rate occurs between infancy and one year of age.
• Between the ages of one and twenty, metabolism decreases by nearly three percent annually.
• Metabolism drops by 0.7% annually after age 60.

After adjusting for other variables, the metabolic rates of men and women are comparable.

The high energy needs of the kidney, brain, liver, and heart organs make up 65% of an individual’s body mass. After age 60, a slower metabolism may indicate that these organs aren’t functioning as well.

Age-related factors

Physiological changes caused by aging may have an impact on weight. Loss of muscle is the main one. We lose roughly 1% of our muscle mass annually starting in middle age, which has an impact on our strength and metabolism (the rate at which we burn calories). “Smaller Muscles consume fewer calories. You will consume more calories than you require if your diet remains unchanged. The extra is kept as fat.

Persistent stress: As we age, stress management becomes more difficult. Additionally, you may have persistently elevated levels of the stress hormone cortisol if you are under a lot of stress. Restoring the body’s energy reserves is one of cortisol’s functions. That may indirectly encourage weight gain in certain individuals by boosting appetite (because the body believes it needs energy) and increasing the amount of unused energy stored as fat. Stress, however, typically results in compulsive behaviors, like consuming “comfort” foods, which are frequently high in sugar, unhealthy fat, excess calories, and salt.

insufficient sleep: Age-related changes have an impact on how well we sleep. Hormones that control appetite may be impacted if you are a chronic “short sleeper,” getting six hours or less every night. Higher levels of hormones that cause hunger, lower levels of hormones that indicate fullness, and higher levels of cortisol are all linked to sleep deprivation.

Sex hormones fluctuate: Certain sex hormones are reduced in older men and women. Low estrogen levels in women are linked to increased body fat and sleep issues. Lower muscle mass in men is associated with lower testosterone levels.

Underlying circumstances

Gaining weight, particularly if it’s recent, can indicate a variety of medical issues. For instance, fluid retention may cause weight gain in a person with heart failure, manifesting as swelling in the feet, ankles, legs, or abdomen. Symptoms like exhaustion or dyspnea would probably accompany this.

• Diabetes and specific renal conditions
• Breathing pauses while you sleep are known as sleep apnea.
• Side effects of medications
• Regular use of some medications can cause weight gain. Certain medications, like prednisone, can cause fluid retention and weight gain.

Additionally, a lot of drugs alter brain chemicals that control appetite, which may increase hunger and lead to overeating and weight gain. Examples consist of

Antidepressants like paroxetine (Paxil) or phenelzine (Nardil); antipsychotics like clozapine (Clozaril) or olanzapine (Zyprexa); beta blockers like atenolol (Tenormin) or metoprolol (Lopressor); and sleep aids like Sominex, Unisom SleepGels, or ZzzQuil that contain diphenhydramine.

Metabolic disorders acquired

Throughout your life, you may develop certain metabolic disorders. Numerous of these metabolic disorders involve hormone imbalances and are endocrine system disorders. Acquired metabolic disorders can result from autoimmune attacks or from diseased or damaged organs. However, there are additional reasons.

Don’t Blame the Pill Right Away

Combination birth control pills (estrogen and progestin) have not been shown to result in long-term weight gain, despite what the general public believes. Although this is typically temporary, it is believed that some women taking the combination pill may gain some weight due to fluid retention. See your doctor if you’re still worried about gaining weight.

Hypothyroidism

You’re likely experiencing fatigue, weakness, and coldness, as well as weight gain, if your thyroid, the butterfly-shaped gland in the front of your neck, is not producing enough thyroid hormone. Your metabolism slows down when you don’t have enough thyroid hormone, which increases your risk of gaining weight. Weight gain may result even from a thyroid functioning at the lower end of the normal range. Some of the weight gain may be reversed if hypothyroidism is treated with medication.

Polycystic ovarian syndrome

Among women of childbearing age, PCOS is a prevalent hormonal issue. The majority of PCOS-affected women develop numerous tiny cysts on their ovaries. The disorder causes hormone imbalances that impact a woman’s menstrual cycle and may result in acne and excess body hair. Women who have this condition may gain weight because they are resistant to insulin, the hormone that regulates blood sugar. These women are more likely to develop heart disease because the weight tends to accumulate around the belly.

Cushing syndrome

Excessive exposure to the stress hormone cortisol can lead to Cushing’s syndrome, which is characterized by weight gain and other abnormalities. If you take steroids for lupus, asthma, or arthritis, you may develop Cushing’s syndrome. It may also result from an excess of cortisol produced by your adrenal glands or from a tumor. The area around the face, neck, upper back, or waist may be where the weight gain is most noticeable.

Giving Up Smoking

One of the best things you can do for your health is to stop smoking. You might gain some weight after quitting, but maybe not as much as you anticipate. People who quit smoking typically gain less than 10 pounds. After a few weeks, you should no longer feel hungry, which will facilitate the loss of any weight you may have gained.

Metabolic disorders that are inherited

A collection of illnesses that impact how your body uses specific nutrients or enzymes is referred to as inherited metabolic disorders, or inborn errors of metabolism. They are the outcome of a genetic alteration (variant) in your DNA. You may inherit them from one or both of your biological parents.

Many of the hundreds of inherited metabolic disorders are uncommon. Here are a few instances:

• Glycogen storage diseases
• Hemochromatosis
• Lysosomal storage disorders
• Maple syrup urine diseases
• Mitochondrial diseases
• Tay-Sachs diseases
• Wilson diseases

Additional possible reasons

Eating late at night may slow our metabolism, increase body fat, and make us more hungry during the day.

The population of bacteria that reside in your stomach (their genes are known as your microbiome) is another suspected cause of weight gain. There is strong evidence that gut microbes may affect blood sugar, metabolism, appetite, and fat storage. Animal studies provide the most strong evidence. The evidence is less clear for humans. The gut microbes of obese individuals differ from those of lean individuals. People who are genetically predisposed to gain weight may have a specific microbiome.

Maintain your weight loss and possibly increase your metabolism

Raise weights

Gaining lean muscle mass will increase your resting energy expenditure. This is because, when at rest, muscle uses more energy than fat. Muscle mass tends to decrease with age in both men and women. In addition to preventing muscle loss, beginning a low-impact weight training regimen can help control blood sugar, enhance balance and coordination, and reduce your risk of injury.

Increase your protein intake

Protein is more crucial than ever since you run the risk of losing muscle mass as you age. A lot of medical professionals advise women over 50 to eat 1 to 1.5 grams of protein for every kilogram of body weight (1 kilogram is equivalent to 2.2 pounds). Beef raised on grass, eggs, and wild salmon are examples of foods high in protein. Think about quinoa, beans, seeds, and organic whey protein powder if you’re a vegetarian or vegan.

Stay away from drastic dieting

Your body may use less energy at rest if you lose a significant amount of weight. A well-researched phenomenon known as “metabolic adaptation” explains how rapid weight loss results in a slower BMR. Naturally, this increases the risk of gaining weight in the future. Fortunately, neither surgically induced weight loss nor gradual weight loss appears to have an impact on metabolism. Eating smaller, more frequent meals and avoiding fasting for longer than three hours can also help maintain a healthy metabolism.

Make healthy eating a priority

Consume a lot of foods high in nutrients, such as whole grains, fruits, vegetables, and lean meats, which have a high ratio of nutrients to calories. Avoid processed foods at the same time because they can be high in sugar, sodium, and “empty” calories. Because calories can add up quickly, think about keeping a food journal to keep track of your choices. Then, look for opportunities to replace processed foods with healthier ones. Some experts advise keeping your scale hidden for the first few weeks if you want to lose weight because it can be demoralizing to see your weight fluctuate or plateau. And have patience: It’s reasonable to lose one to two pounds a week.

Get lots of rest

Menopausal sleep issues and their potential impact on weight gain have already been discussed. A healthy balance of hormones, including those that control metabolism, is supported by getting enough sleep. Make an effort to sleep for at least eight hours every night.

To assist, think about making lifestyle adjustments like:

• Creating a nighttime routine that involves bathing, reading, listening to calming music, or engaging in another soothing activity
• Refraining from taking afternoon or evening naps
• Aiming for a consistent bedtime each night

Regular exercise

The sleep hormone melatonin can be taken as a supplement, but it’s not advised to take it for more than a month or two.

Control your stress

Control long-term stress to reduce stress hormones like cortisol, which can slow metabolism, and raise feel-good hormones like prolactin and dopamine.

The following advice will help you manage your stress levels:

• Take pauses from reading, watching, or hearing bad news.
• Look after your body and mind.
• Make time for your favorite pastimes.
• Spend time with your pals.
• Make connections with religious institutions or your local community.
• Stay away from alcohol and drugs.

The dangers are genuine

Beyond the inconvenience of ill-fitting clothing, weight gain poses serious risks to women as they age. After menopause, there is an increased risk of cardiovascular disease, which is the leading cause of death for women.

After menopause, being overweight can also raise your chance of:

• Cancer of the breast
• Hypertension, or high blood pressure, can cause heart attacks, strokes, and other disorders.
• Diabetes can cause heart disease, stroke, and kidney damage.
• Fortunately, there are many things you can do to keep a healthy weight over time and prevent these health issues.

The dangers of gaining weight in middle age

It may not seem like the worst thing in the world to have love handles or a beer belly. Sadly, it’s not as easy as adding a little extra padding.

This is due to the body going through several hormonal changes in middle age. During the perimenopausal and postmenopausal phases, women’s levels of estrogen decrease, while men’s levels of testosterone do the same. This alters how fat is stored, decreases muscle mass, and makes it more difficult to gain and maintain muscle. In essence, the distribution of fat is different from when you were younger. It is now focused on the abdomen. This type of fat that accumulates in the abdomen and encircles the organs is known as visceral fat.

Metabolic complications are the main cause of such a situation. Living cells that release inflammatory factors are called fat cells. Therefore, they can result in serious, long-term inflammation in the body when they are deposited around the organs.

Your body is less sensitive to insulin when it is inflamed. This is where conditions like high blood pressure, high cholesterol, diabetes, insulin resistance, and fatty liver become relevant. Additionally, this raises the risk of cardiovascular events, such as heart attacks and strokes. Visceral fat is the cause of the chain reaction.

Does weight gain have anything to do with menopause?

Although the metabolic rates of men and women may be similar, women must take into account the impact of menopause as they age. During this phase of life, when menstrual cycles have stopped for a full year, many women gain weight.

Middle-aged weight gain can be influenced by the following factors:

Hormones: Women usually store fat in their hips, thighs, and buttocks from puberty through perimenopause, the period preceding menopause. This fat is found just beneath the skin and is referred to as subcutaneous fat.

Redistribution of body fat to the abdomen occurs during menopause due to low estrogen levels. This fat is stored deep within the abdomen, encircling your organs, and is referred to as visceral fat.

Visceral fat is especially detrimental to your health because it is linked to:

• Resistance to insulin
• High cholesterol
• Type 2 diabetes
• Heart conditions
• Alzheimer’s disease

Aging: As you age, fat usually increases while muscle mass decreases. This is due to an imbalance between cell growth (anabolism) and cell breakdown (catabolism). Muscle loss results from your body’s resistance to normal growth signals (sarcopenia). Your metabolism may slow as a result, making it simpler to gain weight.

Genetic factors: Research indicates that there is a significant genetic component to body fat distribution. If any of your close relatives have excess belly fat, you are more likely to have it yourself.

Lifestyle: During menopause, your habits have a big impact on whether you gain weight or not. If you eat too many calories and are sedentary, you might find yourself gaining weight. (That should come as no surprise.)

Inadequate stress management raises the risk of unhealthy coping strategies like emotional eating, sleep disturbances, anxiety or depression, and an increase in hormones like cortisol, all of which can affect weight. Sleep deprivation may also be the cause. You might snack more when you’re exhausted, which would increase your caloric intake. The body may use less fat for energy as a result of women’s increased nighttime awakenings during menopause, according to recent research. This could eventually result in weight gain and fat storage.

How should you tell if your metabolism is healthy?

Medical professionals use tests to assess your metabolism, or the general health of your body. The basic metabolic panel (BMP) and comprehensive metabolic panel (CMP) are the two blood tests that physicians use most frequently. Every test examines several vital components in your blood. They offer useful details about the metabolism and chemical balance of your body.

For adults, providers typically suggest one of these tests at least once a year. If you have risk factors like diabetes, high blood pressure, or obesity, your doctor might suggest them more often. Numerous metabolic problems can also be evaluated by a number of additional blood tests and urine (pee) tests.

Consult your healthcare provider if you have concerns about your metabolism or experience unusual symptoms, such as fatigue or unexplained weight fluctuations. To better understand your body’s health and assist you in taking proactive measures to improve it, they can suggest the appropriate tests.

Conclusion

Even without significant lifestyle changes, it becomes easier to gain weight as we age due to gradual metabolic changes like decreased muscle mass, slower energy expenditure, and hormonal changes.

Age-related weight gain can be prevented and long-term health supported by maintaining regular physical activity, gaining muscle, and adopting balanced eating habits, even though these processes happen naturally over decades.

FAQs

References

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