Symptoms of a fast metabolism (hypermetabolism) often include unexplained weight loss despite a large appetite, constant hunger, high body temperature, excessive sweating, fatigue, and a rapid heart rate, as your body burns calories very quickly, making it hard to gain weight and sometimes leading to feeling "wired" or jittery.
Signs of Fast Metabolism
That's an ectomorph. Ectomorphs are typically slender with small joints and a light build. They have a narrow frame and fast metabolism, meaning they're often able to overeat without gaining much weight.
Fortunately, lifestyle changes and addressing underlying causes can help to speed up the metabolism.
11. You have a fast metabolism. If your metabolism works overtime, you're probably the envy of all your friends — but as research shows, you're probably almost always hungry, too. That's because the faster your metabolism is, the more you need to eat to feel full.
Sweating More Than Usual: Sweating more than usual can be another sign of a high metabolism. As your body burns more calories, it generates heat, which may lead to perspiration as your body works to cool down.
Understanding Hunger
A metabolic test is performed in order to estimate your BMR or basal metabolic rate. Rather basic and simple, the test commonly involves having the patient breathe into a tube for up to 10 minutes. This is supposed to help calculate the amount of oxygen that was inhaled to the amount of carbon dioxide that was exhaled.
Your metabolic rate does change during your early life, but it plateaus between the ages of 20 and 60, and only decreases by around 1% per year after that. Your total daily energy expenditure also depends on your weight. So, if your body composition changes, your energy expenditure will also change.
Boosts Your Metabolism
Drinking water helps the body burn fat. Studies show that drinking 17 ounces of water can increase the metabolic rate by 30% in both men and women. Even mild dehydration can slow down metabolic rate by 3%.
The bottom line
But metabolism speed is only a small piece of the poop-frequency puzzle. While a faster metabolism can slightly increase the frequency of bowel movements, your number of daily bowel movements is more strongly influenced by diet, fluid intake, and overall gut health.
Ectomorphs, people with a faster metabolism, typically have a smaller frame and bone structure. They are naturally slimmer and leaner and have difficulty gaining weight. Workouts for ectomorphs should emphasize and focus on the individual muscle groups to build muscle mass.
Metabolically, the endomorph metabolism is generally slower than the other two types. This makes it more difficult to lose weight, as their bodies are more biologically prone to holding on to excess fat.
Ten Sure Signs You're Boosting Your Metabolism
“Everyone's body is different, but for most people, eating less than 1,200 calories a day could slow your metabolism enough to make it harder to lose weight,” says Uy. Some signs you have low metabolism include: Weight loss progress that has slowed down. You feel tired or low energy throughout the day.
Being Hungry Does Not Make Losing Weight Easier. You should never think that shedding pounds means being hungry all the time. In fact, managing your ravenous appetite and avoiding hunger pangs is essential if you're trying to burn stored fat deposits.
Aging is strongly related to energy metabolism, but the underlying processes and mechanisms are complex and incompletely understood. Restricting energy intake and reducing metabolic rate can slow the rate of aging and extend longevity, implying a reciprocal relationship between energy metabolism and life expectancy.
There is growing interest and evidence that sleep loss and sleep disorders have a significant impact on metabolism. Laboratory studies have clearly shown that sleep deprivation can alter the glucose metabolism and hormones involved in regulating metabolism, that is, decreased leptin levels and increased ghrelin levels.
Starting between ages 30 and 40, you may find losing weight and exercising more challenging. The exercise you do may not have the same effect as before. It's not necessarily a sign that something is wrong. This weight gain in middle age—known as “middle-age spread”—is a natural consequence of aging.
Home blood testing lets you regularly check metabolic control without coming into the clinic. If you want to test at home, a nurse from the Metabolic Clinic can teach you. Testing is done with a needle stick on the heel or big toe of young children. Older children and adults can take a blood sample from their fingers.
But these steps may help benefit your metabolism and overall health:
If you've ever wondered why some people carry weight in a different way to others, you're actually wondering about metabolism and body types. The concept of metabolic types categorizes individuals into three main body types: ectomorphs, mesomorphs, and endomorphs.
Regional and National Trends in Hunger
The 2025 GHI report finds that hunger is most severe in the regions of Africa South of the Sahara and South Asia, where hunger remains serious. Africa South of the Sahara's high GHI score is driven by the highest undernourishment and child mortality rates of any region by far.
You're feeling really fatigued/tired, having difficulty focusing, and/or feel dizzy and have a headache. You feel on edge, irritable, or the classic term “hangry.” Your stomach feels empty (first stages of hunger) or is growling or in pain (advanced stages of hunger).
But Lennerz and other experts say some foods are more likely than others to crank up those “give me more” cravings. Potato chips are a prototypical “processed carb.” So are refined white or wheat breads, crackers, and other grain-based snack foods.