- Understanding Your Metabolism
- 8 Signs Your Metabolism Is Out Of Whack, Whether It’s Too Fast Or Too Slow
- 1. You’re Really, Really Tired
- 2. Your Moods Are Up & Down
- 3. Your Period Is Irregular
- 4. You’re Feeling Depressed
- 5. You’re Always Hungry
- 6. You’re Losing Hair
- 7. Your Body Temperature Is Off
- 8. You’re Breaking Out
- 9. Your Heartbeat Is Rapid Or Irregular
- Does Metabolism Matter in Weight Loss?
- Fast Metabolism 101: What It Is and How to Get It
Understanding Your Metabolism
It’s not unusual to hear people on a diet complain about a “slow” metabolism or wonder how to get a faster metabolism to speed weight loss, but for all the talk about it, you may be surprised to learn that metabolism is not actually a medical term.
“It’s just a general term that gets thrown around a lot. A lot of people look at it in terms of their weight — whether they can lose or gain weight,” says Priscilla Hollander, MD, an endocrinologist at Baylor University Medical Center in Dallas, adding that she’s not sure there’s even a true definition of metabolism in the way that dieters use the word.
In the scientific community, metabolism refers to the processes in the body that use energy, like breathing, digesting food, and muscle function. Everything that takes place in the body needs energy to work. “All of our cells are like little furnaces, and they all need nutrients to burn,” Dr. Hollander says.
Your Metabolism Can Vary
The rate at which people use this energy — also known as their basal metabolic rate or BMR — can vary. People with a slow metabolism who find it hard to lose weight actually have more efficient approaches to calorie-burning because they consume energy at a slower pace and convert more of it into fat for later use.
“Ten thousand years ago, the more efficient you were, the more likely you were to survive,” Hollander says. “People didn’t know when their next meal was coming along, so the emphasis was on storage.” Those with a so-called faster metabolism, meanwhile, may find it easy to stay slim because their bodies use energy at a higher, more inefficient rate.
It’s not fully understood why some people use up energy faster than others, though genes can play a role in determining the rate of your metabolism. “We do feel there’s some genetic component,” Hollander says. “There have been studies where they looked at families and saw that some family members can inherit a certain body type. Their metabolism is set at a more efficient or less efficient level.”
External factors can also influence your BMR. Many people today have jobs that require them to sit at a desk all day, and many leisure activities, such as Internet surfing, require little physical movement as well. This lack of exercise can cause a person’s BMR to be lower. “People are watching more TV and being less active in their playtime,” Hollander says. “That may play a role in metabolism.”
Your Metabolism and Medical Conditions
Medical conditions can affect the rate of your metabolism as well. Hyperthyroidism, a condition in which the thyroid produces too much thyroid hormone, can cause a person’s metabolism to become too fast, sometimes resulting in unwanted weight loss. Likewise, hypothyroidism, which is characterized by insufficient production of thyroid hormone, can cause a slow metabolism and sometimes weight gain.
Metabolism can be changed to a certain degree, Hollander says. If your metabolism is overactive due to hyperthyroidism, it can be slowed down with prescription drugs, like methimazole or radioactive iodine. If it’s underactive because of hypothyroidism, treatment with replacement thyroid hormone can bring it back to normal levels. But correction of hypothyroidism does not usually result in significant weight loss.
Physical activity can increase the rate at which you use energy. Aerobic exercise like walking not only burns extra calories during the activity, but can also increase the rate at which you use energy when you’re resting. Building muscle mass through strength training can also increase basal metabolic rate. “If you’re doing a lot of muscle work, it does use more nutrients,” Hollander says.
There’s also some evidence that getting enough sleep can have a positive effect on your metabolism. Sleep deprivation can cause an increase in appetite and resistance to insulin, a hormone that helps the body metabolize glucose for energy. These conditions put you at higher risk for obesity and diabetes. To reduce this risk, aim for seven to nine hours of sleep each night. You’ll feel more rested and have more energy for any increase in physical activity that you’re planning.
8 Signs Your Metabolism Is Out Of Whack, Whether It’s Too Fast Or Too Slow
When something is wrong with your health, it can be hard to pinpoint the source of your issues, especially when you have multiple symptoms. One area we might neglect to think about is our metabolism, or the system that converts food into energy. When your metabolism is working properly, it should hum along in the background like a computer’s disk drive without you noticing much. But if it’s out of whack, you may notice signs that your metabolism may be off. It might not be something we think about every day, but our metabolism is an important part of our health, fueling our body’s necessary functions like energy and fatigue, your periods, or even your hair and skin health.
“Typically, when we’re talking about metabolism, you’re referring to your basal metabolic rate (BMR),” Brenna O’Malley, a registered dietitian and founder of The Wellfull, an intuitive eating coaching practice, tells Bustle. “This is the amount of energy your body uses at rest (like when you’re watching Netflix). Your BMR accounts for the majority of the energy you need throughout the day, which means 65-75% of your caloric needs for the day go towards basic functions like keeping your heart pumping and lungs breathing.”
And even though we talk a lot about metabolisms like it’s a one and done deal, Alissa Rumsey, a registered dietitian and nutrition therapist, tells Bustle that everyone’s metabolisms are different, so it’s important to figure out what your “norma;” looks like. “Genetics play a large role in metabolism. Everyone has different metabolisms and no matter what we eat or do, no two people will have the same metabolism,” she tells Bustle.
Your metabolism, like everything else in your body, can be influenced by a lot of factors. “If the hormones that handle your metabolism in the thyroid are altered, due to things like illness or aging, your metabolic rate will actually underperform or overperform,” says Jacqueline Stone, a registered dietitian who specializes in eating disorder recovery, tells Bustle. Dysfunctional eating patterns, such as starvation, can also negatively impact your metabolism, Stone tells Bustle.
If things feel off, consider these eight signs that your metabolism could be out of whack.
1. You’re Really, Really Tired
If you’re tired, all the time, no matter what, it could be a sign of an underactive or slowed metabolism, Stone tells Bustle. When you have issues with your metabolism, it affects how fast your body burns food that gives you energy, especially if your metabolism slows down. When energy in your body isn’t being created fast enough, that’s when you often feel extra fatigued.
“Feeling tired, lethargic, and feeling down are all signs of a metabolism that isn’t working as well as before,” Rumsey tells Bustle. “Our bodies are trying to tell us that something is wrong. If you are feeling run down, it’s most likely your body isn’t getting enough attention.” Rumsey says that trying your best to get enough sleep is one way to set your metabolism back on the right track.
2. Your Moods Are Up & Down
Many of us have experienced negative moods when our hormones are changing (hello, menstrual cycle!), so we know that metabolism can play a role in our mood. Research shows that many neuropsychiatric disorders often co-occur with metabolic disturbances, and manipulating patients’ metabolism via injections of insulin can have striking effects on their mental state, according to The Scientist.
“If you aren’t eating enough, your body will slow down your metabolism in order to protect against starvation,” Rumsey says. This is a case where dysfunctional eating may be having two separate effects that are two sides of the same coin: having mood swings as a result of not eating enough, could also signal that not eating enough may be affecting your metabolism.
If you aren’t eating enough, your body will slow down your metabolism in order to protect against starvation.
3. Your Period Is Irregular
The thyroid gland is responsible for producing hormones that maintain the body’s metabolism, and a symptom of a thyroid problem is irregular periods, according to the NHS. Additionally, lifestyle factors such as excessive exercise or stress can mess up both your period and your metabolism.
4. You’re Feeling Depressed
Mood and psychiatric disorders are often closely tied to metabolic health, and depression could be a symptom of a slowed-down metabolism, Stone says. One study from University of Pittsburgh Schools of the Health Sciences found that identifying and treating metabolic deficiencies in people with treatment-resistant depression can help improve, and sometimes even resolve, their symptoms, implying that there is a link between the two. If your depression becomes difficult to manage and you suspect it is because of irregularities with your metabolism, it is important to see both a general physician and mental health professional in order to figure out the best plan of action to help both issues.
5. You’re Always Hungry
Because your metabolism regulates how what you eat is processed into energy, if your metabolism is accelerated or sped up, you might feel hungry all the time, even if you’re eating and exercising as normal. “Sometimes you feel insatiable, or you’re eating quite often, or you’re just feeling hungry all the time,” Stone says. It’s worth talking to your GP about this change, especially if you haven’t noticed any other changes, as it may be a sign of hyperthyroidism.
6. You’re Losing Hair
Our metabolism regulates nearly all of our bodily functions, including how quickly our hair grows — and, how quickly it sheds, Stone says. One 2018 study found that people with metabolic syndrome — a collection of disorders that include high blood pressure, high blood sugar, and other issues that can increase your risk for heart disease or Type 2 diabetes — were at elevated risk for androgenetic alopecia, a kind of hair loss that’s often seen in people with polycystic ovarian syndrome (PCOS). Even though the study only looked at 100 people, it suggests a connection between the hormones that govern this kind of hair loss, and those that are connected to metabolic syndrome. While losing your hair can be attributable to all kinds of factors, it’s worth talking to your doctor about these or any other changes to get to the bottom of it.
7. Your Body Temperature Is Off
Grace Cary/Moment/Getty Images
The metabolic processes your body uses to convert energy into food are the ones that help your body generate heat. “Our metabolism does increase when we eat because it creates heat in order to burn those calories” for energy, Stone says. So when there are constant issues with your body temperature, this is potentially a sign that points to your metabolism as the issue.
Always feeling cold is a potential effect of dysfunctional eating, as your metabolism slows down in order to prevent starvation, and thus doesn’t generate the body eat you’re used to. On the flip side, Dr. David Greuner of NYC Surgical Associates told Bustle for a previous article on metabolism changes that always feeling hot can be a symptom of an overactive metabolism, because it’s working harder than usual to create energy, aka heat.
8. You’re Breaking Out
Hormone production is part of metabolism, and so drastic changes in your metabolism can become visible on your skin. And although an energy imbalance would not directly cause acne, acne is often strongly associated with other metabolic issues, like PCOS. PCOS causes androgens, or male hormones, to increase count within the body and that this can lead to other more serious hormonal issues, which can eventually lead to difficult-to-treat acne, in addition to hair loss as noted above. If you believe your metabolism issues are more severe, it’s important to see your doctor or OB/GYN in order to test for possible metabolic issues like PCOS.
9. Your Heartbeat Is Rapid Or Irregular
Another potential impact of a too-fast metabolism is a rapid or irregular heartbeat, Stone says. “If the metabolism is much faster, that’s when you feel those side effects of acceleration, such as irregular or rapid heartbeat.” This is, again, because the rate at which your body is converting fuel into energy is higher than what’s “normal” for you.
If you suspect anything may be wrong with your metabolism, it’s best to go see a doctor, who can help you come up with the correct diagnosis and possible treatment. “If you’ve ruled out any underlying issues that may be affecting the metabolism or thyroid, routine exercise, especially anything that builds muscle mass, and eating at regular intervals really helps to keep your metabolism in check,” Stone says.
O’Malley echoes Stone and adds that hydration can help keep one’s metabolism in check. “The basics might be boring but they’re what keeps your body happy and functioning optimally. Adequate sleep and managing stress through activities like meditation or yoga can also maintain your metabolism.”
At the end of the day, though, it’s important to know what’s “normal” for your body in terms of metabolism changes and their side effects. “Nobody has the same genetics,” Rumsey says. “Some naturally have a faster metabolism and some have a slower metabolism, and both are just fine.”
Brenna O’Malley, RD, a registered dietitian and founder of The Wellfull
Alissa Rumsey, MS, RD, CDN, CSCS, Nutrition Therapist and Certified Intuitive Eating Counselor
Jacqueline Stone, MS, RD, CEDRD, LD/N, a registered dietitian and founder of Healthy Rhythm Nutrition
Additional reporting by Syeda Saad
Does Metabolism Matter in Weight Loss?
Published: July, 2015
Do you know people who complain about having a slow metabolism and how they barely eat anything yet still gain weight? Or have you met people who complain about someone they know who can eat whatever he or she wants — including large portions of junk food — due to a fast metabolism and apparently never gain weight. In both cases the individual usually ends by saying, “It’s not fair!” These scenarios raise several very good questions:
- What role exactly does metabolism play in weight gain or weight loss?
- Is your metabolic rate determined by your genes? If so, can you speed up a slow metabolism through exercise, drugs or certain foods?
- Is the importance of metabolism just a myth? Is weight gain or loss purely due to “calories in and calories out?”
The answer to these questions involves a mix of nature (genetic make-up) and nurture (the environment).
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Fast Metabolism 101: What It Is and How to Get It
Weight loss isn’t only about eating fewer calories. Effective weight loss programs also include strategies to speed up metabolism.
Here are eight simple methods.
1. Move Your Body
All body movement requires calories. The more active you are, the higher your metabolic rate.
Even very basic activity, such as standing up regularly, walking around, or doing household tasks, makes a major difference in the long run.
This boost in metabolic rate is technically known as non-exercise activity thermogenesis (NEAT).
In severely obese individuals, NEAT may account for a significant portion of daily calorie expenditure due to the extra weight they have to carry around (3, 29).
There are several ways in which you can boost NEAT. If you spend a lot of time sitting, here are a few strategies:
- Stand up regularly and walk around
- Take the stairs whenever possible
- Do household tasks
- Fidget by bouncing your legs or tapping your fingers
- Chew calorie-free gum (30)
- Use a standing desk (31)
If you have a desk job, using a standing desk may increase the number of calories you burn by 16% (32).
Another 10-person study showed that spending one afternoon standing burned an extra 174 calories compared to sitting (33).
Even seemingly insignificant activities like typing may increase your metabolic rate by 8% compared to doing nothing (32).
In the same way, fidgeting can make a significant difference (34).
One study found that people who sat motionless for 20 minutes temporarily increased their calorie expenditure by 4%, compared to when they lay motionless.
In contrast, fidgeting while seated increased calorie expenditure by a whopping 54% (35).
Regular exercise is highly recommended for anyone who wants to lose weight or improve their health. But even light activities like walking around, doing household tasks, or fidgeting can give you an advantage in the long run.
2. Do High-Intensity Workouts
One of the most effective forms of exercise is high-intensity workouts, also known as high-intensity interval training (HIIT).
HIIT is when exercise involves quick and very intense bouts of activity, such as sprints or fast push-ups.
It significantly speeds up your metabolism, even after the workout has finished — an effect dubbed “the afterburn” (36, 37, 38).
3. Strength Train
Another excellent way to speed up your metabolic rate is to strength train (39, 40).
In addition to the direct effect of the exercise itself, strength exercises promote the growth of muscle mass.
The amount of muscle you have is directly associated with your metabolic rate. Unlike fat mass, muscle mass significantly increases the number of calories you burn at rest (5, 41).
One study showed that doing strength exercises for 11 minutes a day, three times per week, resulted in an average increase of 7.4% in resting metabolic rate after half a year — and an additional 125 calories burned per day (40).
Old age is generally associated with muscle loss and drops in metabolic rate, but regular strength exercise can partially counteract this adverse effect (42, 43).
Similarly, a calorie-reduced weight loss diet often results in the loss of muscle mass and metabolic rate. Again, strength training may help prevent this decline (44, 45).
In fact, a study in overweight women showed that doing daily strength exercises on an 800-calorie diet prevented decreases in muscle mass and metabolic rate, versus those who didn’t exercise or only did aerobics (46).
4. Eat Protein
Eating adequate amounts of protein is essential if you want to build or maintain your muscle mass. But dietary protein also has other important qualities.
All food leads to a temporary increase in metabolic rate, known as the thermic effect of food (TEF). However, this effect is much stronger after eating protein compared to carbs or fat (47).
In fact, protein may increase metabolic rate by 20–30%, whereas carbs and fat cause a 3–10% increase or less (48).
This boost in calorie expenditure may help promote weight loss or prevent weight regain after a weight loss diet (49, 50, 51).
TEF is highest in the morning or during the first few hours after you wake up. For this reason, eating a large proportion of your daily calories early in the day can maximize the effect (52, 53).
Eating high amounts of protein can also help counteract the loss of muscle mass and metabolic rate associated with weight loss (54, 55, 56).
5. Don’t Starve Yourself
While eating less is a key weight loss method, eating too little is usually counterproductive in the long term.
That’s because calorie restriction causes a decrease in your metabolic rate.
This effect is known as starvation mode or metabolic adaptation. It is your body’s way of warding off potential starvation and death.
Research shows that consistently eating fewer than 1,000 calories daily leads to a significant drop in metabolic rate that sticks around even after you stop dieting (57, 58, 59).
Studies in obese people suggest that the starvation response may significantly reduce the number of calories burned. For instance, one study indicates that this slowdown in metabolic rate spares up to 504 calories per day (60, 61).
Interestingly, intermittent fasting seems to minimize this effect (62, 63).
6. Drink Water
Temporarily boosting your metabolic rate doesn’t have to be complicated. It’s as simple as going for a walk or drinking a glass of cold water.
Many studies show that drinking water leads to an increase in the number of calories burned, an effect known as water-induced thermogenesis (64, 65, 66).
Drinking cold water has an even greater effect than warm water, as this requires your body to warm it up to body temperature.
Studies on this phenomenon provide varying results. About 16 ounces (500 ml) of cold water may cause a 5–30% increase in the number of calories burned for 60–90 minutes afterward (64, 66, 67, 68).
It seems that increasing your water consumption is also beneficial for your waistline. Several studies show that drinking 34–50 ounces (1–1.5 liters) of water daily may lead to significant weight loss over time (64, 69).
You can maximize these benefits by drinking water before meals, as it also fills you up and reduces calorie intake (70).
7. Drink Caffeinated Beverages
Although plain water is good on its own, caffeinated, low-calorie beverages, such as coffee or green tea, are useful as well.
Controlled studies show that drinking caffeinated beverages can temporarily speed up your metabolic rate by 3–11% (71, 72, 73, 74).
However, this effect is smaller in obese people, as well as older adults. Additionally, seasoned coffee drinkers might have built up a resistance to its effects (75, 76).
For weight loss purposes, sugar-free beverages like plain, black coffee are best. Like water, cold coffee may be even more advantageous.
8. Get Good Sleep
Getting inadequate sleep is not only bad for your general health, but it may also slow down your metabolic rate and increase your risk of weight gain (77, 78).
One study showed that metabolic rate decreased by 2.6% when healthy adults slept for only four hours per night for five days in a row (77).
Another five-week study determined that sustained sleep disruption, along with irregular sleeping times, reduced resting metabolic rate by 8%, on average (78).
Accordingly, lack of sleep is associated with an increased risk of weight gain and obesity (79, 80, 81, 82).
SUMMARY There are numerous things you can do to boost your metabolism. These include drinking cold water, sipping on coffee, getting more sleep, exercising, and eating protein.