The number of calories your body burns for fuel largely determines your metabolic rate—and some people are known to have a faster metabolism compared to others meaning their bodies tend to burn more calories in a given time frame. So you may be wondering whether you have a fast metabolism—and if there are any signs that could clue you into this possibility. Check your levels of three key hormones that affect metabolism and weight cortisol, testosterone, and thyroid-stimulating hormone or TSH with the easy-to-use, at-home Metabolism Test.
Note that this test does not give you a measurement of your metabolic rate. Your metabolism, and your basal metabolic rate sometimes referred to as just metabolic rate , is significantly influenced by genetics. Wondering how to tell if you have a fast metabolism? The Everlywell at-home Metabolism Test lets you check 3 key hormones commonly associated with metabolism and weight to help narrow down possible causes and determine whether a hormone imbalance may be affecting your metabolism.
Having a high basal and resting metabolic rate means that your body naturally burns more calories in a state of rest than someone with a lower metabolic rate. This means that the faster your metabolism is, the more calories your body needs. For years, researchers have been documenting a phenomenon called "metabolic adaptation" or "adaptive thermogenesis": As people lose weight, their basal metabolic rate — the energy used for basic functioning when the body is at rest — actually slows down to a greater degree than would be expected from the weight loss.
To be clear: It makes sense that losing weight will slow down the metabolism a bit, since slimming down generally involves muscle loss, and the body is then smaller and doesn't have to work as hard every minute to keep running.
But the slowdown after weight loss, researchers have found, often appears to be substantially greater than makes sense for a person's new body size. In the newest scientific study to document this phenomenon, published in the journal Obesity , researchers at NIH followed up with contestants from season eight of the reality TV show The Biggest Loser. By the end of the show, all of the participants had lost dozens of pounds, so they were the perfect study subjects to find out what happens when you lose a dramatic amount of weight in a short period of time.
The researchers took a number of measurements — bodyweight, fat, metabolism, hormones — at both the end of the week competition in and again, six years later, in Though all the contestants lost dozens of pounds through diet and exercise at the end of the show, six years later, their waistlines had largely rebounded.
Thirteen of the 14 contestants in the study put a significant amount of weight back on, and four contestants are even heavier today compared with before they went on the show. But the participants' metabolisms had vastly slowed down through the study period. Their bodies were essentially burning about calories fewer about a meal's worth on average each day than would be expected given their weight. And this effect lasted six years later, despite the fact that most participants were slowly regaining the weight they lost.
Sandra Aamodt, a neuroscientist and author of the forthcoming book Why Diets Make Us Fat , explained this may be the body's way of vigorously defending a certain weight range, called the set point. Once you gain weight, and keep that weight on for a period of time, the body can get used to its new, larger size. When that weight drops, a bunch of subtle changes kick in — to the hormone levels, the brain — slowing the resting metabolism, and having the effect of increasing hunger and decreasing satiety from food, all in a seeming conspiracy to get the body back up to that set point weight.
In the Biggest Loser study, for example, the researchers found each participant experienced significant reductions in the hormone leptin in their bloodstreams.
Leptin is one of the key hormones that regulate hunger in the body. By the end of the Biggest Loser competition, the contestants had almost entirely drained their leptin levels, leaving them hungry all the time. At the six-year mark, their leptin levels rebounded — but only to about 60 percent of their original levels before going on the show.
But not every kind of weight loss in every person results in such devastating metabolic slowdown. For example: That great effect on leptin seen in the Biggest Loser study doesn't seem to happen with surgically induced weight loss. Indeed, all the researchers I spoke to thought the effects in the B iggest Loser study were particularly extreme, and perhaps not generalizable to most people's experiences.
That makes sense, since the study involved only 14 people losing vast amounts of weight on what amounts to a crash diet and exercise program.
The Mayo Clinic's Jensen said he hasn't found in his patients as dramatic a slowing of the metabolism in studies where people lose about 20 pounds over four months.
With slow, gradual weight loss, the metabolic rate holds out really well. There are some interesting hypotheses, however. One of the most persistent is an evolutionary explanation. That ability would to some extent increase our ability to survive during periods of undernutrition, and increase our ability to reproduce — genetic survival. Today, the thinking goes, this inability to keep off weight that's been gained is our body defending against periods of undernutrition, even though those are much rarer now.
But not all researchers agree with this so-called "thrifty gene" hypothesis. When asked to write down everything they've consumed in a day, many people tend to report eating far less than they actually do. More often than not, the reason you're putting on weight is not because of a slow metabolism, it's because you're eating and drinking more calories than you're burning. It may be hard to accept, but staying on top of the number of calories you eat is key to losing weight and keeping it off.
Our week weight loss plan will help you lose weight by tracking your calories. With some diets, your body is forced to break down muscle to use for energy. The lower your muscle mass, the slower your metabolism. With less muscle and a slower metabolism, it then becomes a lot easier to put body fat back on after coming off the diet. It's claimed that certain foods and drinks can boost your metabolism, including green tea, black coffee, spices and energy drinks.
The evidence behind these claims is weak or they are not effective long-term solutions. While you do not have much control over the speed of your metabolism, you can control how many calories you burn through your level of physical activity. Some people who are said to have a fast metabolism are probably just more active — and maybe more fidgety — than others.
Aerobic exercise is the most effective way to burn calories. You should aim to do at least minutes of aerobic activity, such as walking, cycling and swimming, a week.
You can achieve this target by doing 30 minutes, 5 days a week and breaking down your activity sessions in chunks of 10 minutes. To lose weight, you're likely to need to do more than minutes a week and make changes to your diet. Aim to do muscle-strengthening activities that work all major muscle groups legs, hips, back, abdomen, chest, shoulders and arms on 2 or more days a week. Examples of muscle-strengthening activities include lifting weights and high-intensity bouts of exercise.
Heavy gardening may also do the job. Controlled studies in lean and overweight people confirm that consuming fewer than 1, calories per day can have a significant impact on your metabolic rate 1 , 2 , 3 , 4 , 5. Most studies measure resting metabolic rate, which is the number of calories burned during rest. Yet some also measure calories burned during rest and activity over 24 hours, which is referred to as total daily energy expenditure.
In one study, when obese women ate calories per day for 4—6 months, their resting metabolic rates slowed down significantly. In another study, overweight people were asked to consume calories per day. After 3 months, their total calorie expenditure dropped by calories on average 4. In a 4-day study in 32 people, the resting metabolic rate of those who ate 1, calories per day slowed more than twice as much as that of those who consumed 1, calories.
However, weight loss was similar for both groups 5. Eating enough protein is extremely important for achieving and maintaining a healthy weight. In addition to helping you feel full, high protein intake can significantly increase the rate at which your body burns calories 6 , 7 , 8.
The increase in metabolism that occurs after digestion is called the thermic effect of food TEF. The thermic effect of protein is much higher than that of carbs or fat. Although metabolic rate inevitably slows during weight loss and continues to be slower during weight maintenance, evidence suggests that higher protein intake can minimize this effect. The diet highest in protein reduced total daily energy expenditure by only 97 calories, compared to — calories in people who consumed less protein Another study found that people needed to eat at least 0.
Notably, many people have lifestyles that mainly involve sitting at work, which can have negative effects on metabolic rate and overall health Although working out or playing sports can have a major impact on the number of calories you burn, even basic physical activity, such as standing up, cleaning, and taking the stairs, can help you burn calories. One study found that a high amount of NEAT could burn up to 2, additional calories per day. However, such a dramatic increase is not realistic for most people Working at a standing desk or simply getting up to walk around several times per day can help increase your NEAT and prevent your metabolism from dropping.
0コメント