How to gain weight when you have a fast metabolism

Your body is constantly using energy to function, whether you’re exercising, walking, or watching TV on the couch. Even if you are inactive or sleeping, your body is still using energy to keep your heart beating, maintain respiration, and rest and repair the body.  

The ultimate source of your body’s energy comes from the food that you eat, which then gets broken down into different chemicals and nutrients during the digestion process and converted into energy. Your metabolism determines how your body uses that energy to maintain normal functioning. Your basal metabolic rate is the baseline amount of energy your body needs for normal resting functions like breathing and maintaining stable body temperature.

You may be surprised to learn that up to 80 percent of the energy your body uses in a day is used in its resting state, and between 10 and 20 percent is used in normal day-to-day activities like walking. Approximately 5–10 percent of your body’s energy is used in the digestion process.

High metabolism definition  

If you have a ​high metabolism​, or a fast metabolic rate, it means your body uses energy (or burns calories) more rapidly than someone with a slower metabolism. Many different factors can influence your metabolic rate, such as sex, weight, hormone function, age, and physical activity levels. Generally speaking, the leaner your body mass, the faster your metabolism is.

Signs of a fast metabolism 

Since we know that metabolic rates can be variable, you might be asking yourself, “​how fast is my metabolism​?” There are a few signs that you might have a ​fast metabolism:​  

• You have difficulty gaining weight or keeping weight on, even though you eat regularly.
• You have a high body temperature, even when you are resting.
• You are often hungry or have an insatiable appetite, even after eating meals or snacks.
• You have an irregular menstrual cycle or you miss your period even though you aren’t pregnant.
• You may need to urinate frequently because your body’s processing speed is increased.

If you think you have a ​fast metabolism​ and you have an increased appetite, make sure you are eating nutritious meals to reduce the risk of ​binge eating​ unhealthy foods.  

Talk to your health care provider if you are concerned about your symptoms or if your body is under acute stress, which could indicate illness or a chronic health condition.

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To increase lean muscle mass in your body, you can try increasing your physical activity to include strength training exercises. Other ways to boost metabolism​ include:  

• Staying hydrated by ​drinking more water
• Getting enough uninterrupted sleep
• Eating healthy, nutrient-dense foods
• Managing your stress levels

Even though you may be trying to burn more calories than you consume, be sure not to ​starve yourself​, as this could actually signal your body to protect its fat stores rather than use them for fuel.

If you have a ​fast metabolism​, it means your body burns calories at a higher rate, so try eating more food to gain weight. Be mindful of what you eat, however, because consuming too many ​refined sugars​, found in candy or sugary drinks​, can have negative effects on your health.

Try to increase your calorie intake by eating more frequently, having larger meals, and choosing foods with natural sugars that are found in whole grains or fruit.

Exercise, such as strength training, can help you build up your muscles and thus gain weight. Also, it can stimulate your appetite.

It’s not impossible to gain weight with a ​fast metabolism, but ​you need to eat healthy foods that are higher in calories. Try incorporating the following foods into your diet: 

• Nuts and seeds
• Carbohydrate-rich foods like whole-grain pasta, bread, and rice
• Protein-rich foods, including legumes
• Natural high-sugar foods like fruit

Make sure you’re eating regularly and often. ​Eat at least three full meals per day, with snacks in between. It’s also important to be mindful of how many calories you’re burning in a day, and make sure that you aren’t burning more calories than you consume.

Some people might think that having a fast metabolism is better than a slow metabolism, but not everyone who has a fast metabolism likes it, especially if they want to gain weight. Some people with a fast metabolism might also be more susceptible to bingeing on foods like candy or desserts. But just because you can eat certain foods without gaining weight doesn’t mean all of it is good for your health.

Diet is just one part of your overall health. Check out ​Flo.health​ for more articles about improving your health and wellness through diet, exercise, and lifestyle changes.

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