How to Increase Metabolism After 40

Table of Contents

• Metabolism Basics
• Does Metabolism Slow Down with Age?
• Can You Boost Metabolism?
• How to Increase Metabolism after 40?
• Metabolism Boosting Foods for Over 40
• Bottom Line

Your body goes through various transformations as the years go by, which are all a natural part of aging. Among many physiological changes, you might notice that you start to gain weight and that your energy levels dip slightly. Chances are these changes reflect a slowdown of your metabolism, which can understandably make you worried. 

Some people accept this as a regular part of aging, but there are things you can start doing now to address a sluggish metabolism. Let’s dig deeper into the subject and find out how your metabolism works, how it decreases with age, and how you can increase metabolism after 40.  

Metabolism Basics

Before we answer the title question, let’s first define what metabolism is.

Metabolism encompasses all of the chemical reactions that occur within your body to keep you alive. These include all of the actions your body performs, such as breathing, tissue repair, and blood circulation, as well as food digestion and energy production [1]. 

Now, we’re going to quickly explain a few key terms you need to know to understand the concept of metabolism.  

• Your body burns energy even when you’re resting, and it’s termed the “resting metabolic rate” or “basal metabolic rate” [2]. 
• Your body also burns calories while digesting and absorbing food, and this is termed the “thermic effect of food” [2]. 
• The third main component of metabolism is the “energy expenditure for physical activity,” which includes exercise and non-exercise-related activity [3].

The total of these components makes up the “total energy expenditure” per day, which is a major determinant of weight fluctuations.

Does Metabolism Slow Down with Age?

To come back to the original question, yes, aging can affect metabolism. In addition to age, several other factors, such as your gender, body composition, and body size, can affect your metabolism as well [1].

There are a few different ways age can influence your metabolism.

It can slow down your bodily functions, thus decreasing your basal metabolic rate [4]. In fact, research studies suggest that your resting metabolic rate can slow down by 1-2% every 10 years after 20 years of age [4].

One study in particular, however, presented a different finding, stating that the basal metabolic rate of an individual does not begin to decline until after the age of 60 [5]. 

Apart from these factors, lifestyle changes such as a decrease in activity levels can slow metabolism as you age. Your body composition might change with age, leading to a loss of muscle mass [6], which in turn results in a slower metabolism as muscle mass uses far more energy (aka calories) than fat cells in a resting state [7].

Another contributing reason can be hormone-related conditions such as hypothyroidism [8].

Can You Boost Metabolism?

So, what can you do if you notice that your metabolism has slowed down? 

There’s no reason to worry—you can certainly support your metabolism by making a few changes in your lifestyle, no matter your age [1]. Increasing the amount of energy you burn per day is one way to give your metabolism a boost.

Here are a few practical tips on how to boost your metabolism after 40.  

How to Increase Metabolism after 40?

Here are a few ways you can improve your metabolism even if you are 40+:

Stay active throughout the day

You don’t have to do intense workouts to increase your metabolism. Any form of physical activity burns calories. These can include planned exercise or just your day-to-day activities such as walking, cleaning, or even fidgeting [9]. 

Find physical activities you enjoy, such as walking, swimming, or cycling, and do them regularly. Limit the time you spend doing sedentary activities such as watching TV.

By increasing your activity levels, you increase what’s called nonexercised activity thermogenesis or NEAT, which roughly rounds up to 100-800 calories per day [2].

Choose the right type of exercise

While all exercises burn calories, certain types of workouts increase the metabolic rate and keep it elevated even after the workout is over.

For instance, the forms of exercises called HIIT (High-Intensity Interval Training) and resistance training have been shown to increase the metabolism for around 14 hours after the exercise sessions [10]. 

Build more lean muscles

On a related note, include a few sessions of strength training in your workout routine to build muscles. Increasing your protein intake also helps to build muscles. This boosts metabolism because the added calories in nutrient-dense foods can help build muscle mass and maintain it [7]. Moreover, those who have more lean muscle mass than fat mass tend to have a higher basal metabolic rate [7]. 

You may also like: Strength Training For Women Over 40

Eat a sufficient number of calories

Make sure you eat enough to sustain your bodily functions. Studies have found that eating a very low-calorie diet suppresses the resting metabolic rate [11]. Keeping your calorie intake sufficient is a proven way to boost your metabolism after 40.  

Make sure you get a high-quality sleep

Sleep deprivation has been found to reduce energy expenditure [12]. This can cause low levels of activity that can happen due to daytime sleepiness or lethargy following a night of insufficient sleep.

Scientists also speculate that sleep deprivation can cause imbalances in hormones such as ghrelin and leptin, which adversely affect energy metabolism [12].

Ghrelin and leptin are both hunger hormones. Ghrelin increases your appetite by signaling to the brain the stomach is empty, while leptin suppresses appetite when you are full and have enough energy stored [21] [22].

Drink enough water

Now, this might seem unrelated, but hear us out. Studies show that drinking water speeds up energy expenditure through a process called ‘water-induced thermogenesis’ [13]. Although the underlying mechanism is unclear, research suggests that drinking 2 liters of water per day can increase the amount of energy spent by 400kJ [14].

On the other hand, mild dehydration has been shown to slow down metabolism [13]. 

So, if you want to jumpstart your metabolism after 40, it’s a good idea to increase your water intake. 

Control your stress levels

Stress is another factor that significantly slows down metabolism [15]. 

Practice stress-management techniques like meditation, yoga, or breathing exercises. Seek professional help if you feel you can’t control your stress levels on your own. 

Get your thyroid levels checked

Thyroid-related conditions such as hypothyroidism can also make your metabolism slow down [8]. If you keep feeling tired and gaining weight despite making these lifestyle changes, get your thyroid levels checked by your doctor.

Metabolism Boosting Foods for Over 40

In addition to the strategies mentioned above, certain foods can help boost your metabolism. Here, we list a few such foods that you can eat to speed up your metabolism after 40.

• Proteins: High-protein foods have been shown to increase metabolism [16]. Protein raises the thermic effect of food, thereby spending a higher number of calories for its digestion and processing [16]. Protein also helps to build muscle mass, thus leading to an increased metabolism [17]. 

You can boost your metabolism even after 40 by including protein-rich foods such as meat, eggs, and legumes in your diet. 

• Spicy food: Studies report that spicy foods—especially those containing a compound called capsaicin (such as chili peppers)—can speed up metabolism [18]. 
• Caffeinated foods and drinks: Caffeine has been proven to increase fat metabolism in the short term both after resting and after exercising [19]. However, be mindful of the amount of caffeine you ingest, as it can affect your sleep.
• Green tea: Green tea is another beverage you can incorporate into your diet to increase your metabolism after 40. Green tea extract has been shown to improve fat oxidation during rest and exercise conditions [20].  

Bottom Line

You might notice certain changes in your body when you’re approaching your 40s, including slowing down of your metabolism. Several factors contribute to this change, such as loss of muscle mass, hormonal fluctuations, and decreased activity levels. Although this is a completely normal consequence of aging, it can be reversed or, at least, delayed.

So, how can you increase metabolism after 40? You just have to make a few changes in your lifestyle to boost your metabolism after 40, or at any age, for that matter. These include changing up your diet to add more metabolism-boosting foods, increasing your physical activity levels, and adding a strength training component to your exercise regimen. 

Making these changes will increase your energy levels, improve your overall health, and help you better manage your weight as you age.