15 Tips on How to Gain Weight With a Fast Metabolism

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Gaining weight is slow for everyone – but it can be more challenging if you have a fast metabolism.

Today we’re discussing how to gain weight with a fast metabolism – how to get more calories, gain quality weight, and build muscle the healthy way.

Let’s start with a look at how weight gain works – so you know what you need to do to change your body weight.

ectomorph body type

Gaining Weight: Calorie Surplus and Muscle Mass

Weight gain happens when you eat more calories than you use. Your calorie intake is the result of eating food, and a healthy diet typically balances your needs and energy consumption (1).

Weight gain occurs when your calorie intake is higher than your maintenance needs.

On the opposite side of the spectrum, weight loss happens when your body’s energy intake is below its needs – and body fat is burned to make up the shortfall.

Weight gain foods list

Your maintenance caloric intake needs – your total daily energy expenditure – is made up from:

  • Your basal metabolic rate – the energy needed to maintain your body at-rest
  • Your non-exercise activity – such as moving around, fidgeting, and other basic movement
  • The energy expended in exercise and other forms of deliberate activity

These produce your “calories out” and you need to eat more calories to build mass. Your weight gain journey starts with this simple principle – and, even with a fast metabolism, this is how your body works.

Healthy Weight Gain vs Fat Gain

Body mass changes can happen through muscle growth or loss, and fat loss or gain. These refer to the quality of weight gain.

If you eat more calories with proper nutrition and exercise (here are some weight gain exercises), you’ll experience muscle growth. However, without protein rich foods, you’ll just gain body fat.

Equally, unhealthy weight loss happens when you’re burning muscle mass or you drop below a healthy body weight.

You probably don’t want to gain mass – you want to build muscle and improve overall health. Generally speaking, that means you need to:

  1. Consume a relatively small amount of extra calories above maintenance (250-750)
  2. Eat protein rich foods to improve weight gain quality
  3. Perform regular, and progressive, strength training

These are the 3 pillars of muscle growth and proper weight gain, and they make the difference between gaining weight as fat or muscle.

Even with a fast metabolism, you can’t go wrong following this basic template for muscle growth, weight gain, and a more well-balanced diet.

fast metabolism weight gain

What is Fast Metabolism – and How Does it Work?

People with a fast metabolism just have a higher basal metabolic rate, or a higher total daily energy expenditure. Either they have a naturally high energy requirement, or the body burns more energy through higher activity levels.

This can make it harder to gain weight and spur muscle growth, as you’re constantly fighting to eat enough calories.

You may also experience unwanted weight loss, which can be a real problem for maintaining a healthy body weight with a fast metabolism.

gain healthy weight

Can You Still Build Muscle with a Fast Metabolism?

Yes – you can still build muscle with a fast metabolism.

Most people with a fast metabolism worry that muscle growth and weight gain will be impossible – but it’s still just the same as everyone else. You gain weight when you eat more than you use, and people with a fast metabolism will simply need to eat more than other people.

As with everyone else, it’s just about tipping the scales towards more energy in than energy out. With a faster metabolism, you just start with the scales loaded towards weight loss.

Get plenty of food, and you’ll tip it back in favor of your recovery and growth goals!

Calorie Needs Are Personal and Individual!

Remember that how much you eat – and how much is “too much” – is a personal balance.

Healthy dieting has to reflect the balance of your needs and goals, and calorie dense foods that are unhealthy for other people might be exactly what you need to gain weight fast.

Having a high metabolism is a personal nutritional need and will require you to properly organize your diet plan around your metabolic rate. Don’t get caught up with other people’s needs or “normal”.

How To Gain Weight With A Fast Metabolism?

To gain weight with a fast metabolism, you just have to eat more. That might mean eating a lot more than other people, but the important part is that you eat a calorie surplus to push the weight on the scales up – around 0.5lbs per week, if you want to keep fat mass lower.

Even if you think you’re eating a lot now you need to rely on the scale. If your weight doesn’t change, you’re not gaining weight and need to eat more.

If you’re determined to build muscle and gain weight, there are a few things you can do to improve your weight gain process.

1. Track Your Progress

If you’re not tracking your food intake, you’re just guessing at whether or not you’ll gain weight. Eating more comes from knowing how much you’re eating now, and increasing your calorie intake slowly over time.

This means that calorie intake and macro trackers – like MyFitnessPal – are a great tool. They help you determine how much more you need to eat, and provide some nutrition self-education along the way.

Track your calories, protein, and carbs at a priority. They’ll be the main driving force in muscle growth – and you need to pay attention.

2. Portion-up

This is obvious; take your normal meals and add 10-20% to the portions. It’s a simple way to increase your calorie intake without radically changing your diet.

It’s also in-line wit the calorie goals we set for bulking up and building muscle (around 10-20% calorie surplus).

Your metabolism is a little faster than others’, so your meals should be a little bigger. This helps you consume more calories, boost your energy reserves, and account for a fast metabolism.

You’ll also be able to do this easily with snacks and side-meals, like protein shakes or mass gainer shakes. These are just a mixture of powder and liquid, so you can portion up very easily – or just take your normal portion twice a day. Gaining weight doesn’t have to be complicated!

3. Less-lean Meats

Try eating fattier cuts of meat as your protein source. If you’re only ever eating chicken breast and 3% fat turkey mince, it will be hard to gain weight. The added calories of fattier cuts will make for better eating and a stronger calorie intake, even with the same “format” for your meals.

A universal approach to meal construction is meat, carb, and veg. With fatty meats like 10% fat beef mince, pork belly, or chicken thighs and wings, you’ll be able to get plenty of protein with a few more calories.

Combining these cuts with a green veg is perfect to keep them healthy and maximize results, supporting better digestion and metabolism.

4. More Protein

Weight gainer shakes

Protein is your best friend for weight gain quality – and some of the best protein sources are nutritious while not crushing your appetite. Equally, some other protein options are great mixed-nutrient foods, providing plenty of carbs and calories, too.

Great protein source examples include:

  • Salmon and other fatty fish
  • White fish like Cod and Basa
  • Seafood – like oysters and shellfish (if you can)
  • Lean meats and poultry (like chick wings and thighs)
  • Beans, pulses, and legumes
  • Cultured dairy – like cottage cheese and natural set yogurt

These are a few examples that should be top priority for everyone.

When you’re trying to bulk up with a fast metabolism, you should focus on combining these with other energy dense protein sources – like protein shakes with added carbs, low-fat yogurt with fruit and granola, or just lean meats sauteed in olive oil for calorie dense healthy fats.

5. More Carbs

Carbs are the primary energy source for lifting weights and building muscle. They’re the short-term energy your body needs to consume in order to signal for short-term energy availability, which goes to improve muscle growth.

Carbs are also less filling than protein or fats on average.

This makes carbohydrates a perfect place to eat more without getting too full, too fast. Rice, potatoes and sweet potatoes, pasta, noodles, and whole grains are all perfect carbs for improving energy levels and muscle gains.

Eating more of these foods is easy, and you’d typically combine them with a protein source in any meal – but you can also use them as snacks.

This combination makes carbs the easiest way to eat more, gain more, and fuel up for better workouts – whether that’s lifting weights, cardio, or other intense exercise.

6. Eat More Often

If you get full quickly, you should eat more often. The turnover of food can usually be faster, with eating every 3-4 hours as opposed to at set times through the day. The more often you eat, the more total calories you’re likely to get into your day.

This is a great way to beat hunger – as appetite is one of the keys to better food intake and muscle gains.

Shifting from 3 meals a day (small breakfast, medium lunch, big dinner) to 4-6 could be an easy way to improve both the quality and quantity of your food intake.

It still requires some effort – especially if you’re working during the day with limited access to food – but it’s doable for most people.

You can invest in a mass gainer or meal replacement shake if you’re struggling to eat regularly through the day.

7. Weight Gainer Supplements

shakes for weight gain

Weight gainer supplements – both appetite stimulants and mass gainer shakes – can be a great tool to help hard gainers gain weight. The basic idea is to boost your appetite and increase real food intake or, if you can’t eat more often, to use shakes to increase calorie intake.

Weight gainers come in many shapes and sizes but they either support better food intake (and hormonal and metabolic health), or they directly give you the calories you need from protein and carbs. This makes them a great support choice for hard gainers.

Mass gainer shakes are easy to use through the day – and you can get large tubs for a decent price (compared to food).

Even a single serving of around 500 calories with 25-50g of protein is a great way to give your body more resources to build muscle. This can completely change your diet with just one added shake per day.

You can also make homemade mass gainers with a protein powder and carb powder (like cyclic dextrin or oat flour).

These are a little more work and may not last as well through the day, but they’re cheaper still and can be used with whatever ingredients you want.

8. Extra Calorie Tricks

The best way to gain weight with a fast metabolism is to eat more real food – and the last 7 tips are important for that. However, there are ways you can add more calories to your diet fairly easily as well to improve your weight gain.

These aren’t the best, healthiest, or smartest ways to gain weight – but they’ll get the job done if you’re desperate. Here are the quick and dirty ways to gain weight with a fast metabolism:

  • Ice cream: tons of calories and semi-liquid to beat fullness, use with caution.
  • Cheese: melt cheese onto more things – it’s full of calories, just select good cheeses.
  • Full fat milk: a timeless addition to a diet for more calories with a decent protein content.
  • Drink your calories: juice, milk, shakes and smoothies all offer easy calories – just avoid soda.
  • Calorie rich sauces: add sauces and other extras that are rich in calories (like pesto).
  • Rotate: set basics that you need for each meal (e.g. meat) and rotate the rest to maintain variety.
  • Blend: blending ingredients like peanut butter, bananas, and oats into shakes is a powerful weight gain hack.

These aren’t the best – or the only – options out there.

The diet should improve all together, but these can save you if you’re in a pinch and need more calories to keep your muscle gain diet ticking over.

Don’t rely on them as your main source of calories, but be willing to commit to ‘unhealthy’ options occasionally to improve your total intake and consistency!

Calories And Weight Gain: How Many Calories to Gain Healthy Weight?

First, maintain a healthy calorie surplus to gain weight fast – but not too fast. If you’re eating too far above your calorie needs, you’re going to cause health problems, as you have a consistent excess of energy – even beyond what you need for muscle growth.

This can damage metabolism, especially if you’re mostly eating saturated fats from processed foods.

You should try to keep your calorie deficit around 10-20% of your TDEE to prevent excessive weight gain.

The more patient you are – and the more you rely on healthy foods – the better quality of results, as well as supporting things like immune function.

Why Should You Gain Weight Slowly?

Keeping weight gain slow means staying in control and improving your end results and the experience. You’ll build more muscle, less fat, and be healthier along the way.

It’s not just about how to gain weight with a fast metabolism, it’s about how to gain the best possible weight. The pace changes what that weight is, how you recover, and how you feel during a weight gain diet.


The best results in both health and physique come from taking your time. Your body has a limit on how fast it will let change happen, and that includes things like genetic limits on muscle growth, metabolic change, and hormonal damage if you’re going too fast.

Consider the health and physique implications of just focusing on speed, and try to prioritize healthy foods: unsaturated fats, whole grains, and nutrient-dense whole foods.

gaining weight with fast metabolism

Protein and Healthy Eating For Weight Gain

Protein intake determines what you gain, when gaining weight. Higher protein diets cause less fat mass gain during a weight gain diet, which is an important way to control your physique change.

You want to gain muscle mass – not just indiscriminate “mass”!

Healthy Eating Protein Sources for Weight Gain

Healthy eating – as mentioned above – is still important here. Even with a fast metabolism, you should focus on whole foods rich in protein, vitamins, and minerals. Examples include:

  • Salmon and other fatty fish
  • White fish like cod and Basa
  • Seafood – like oysters and shellfish (if you can)
  • Lean meats and poultry
  • Beans, pulses, and legumes
  • Cultured dairy – like cottage cheese and natural set yogurt

These are a few examples that should be top priority for everyone. When you’re trying to bulk up with a fast metabolism, you should focus on combining these with other energy dense protein sources.

For instance, protein shakes with added carbs, low-fat yogurt with fruit and granola, or just lean meats sauteed in olive oil for calorie dense healthy fats are great foods.

Do You Need Protein Shakes to Gain Weight?

Protein shakes can support high-quality weight gain with a fast metabolism – but they’re not essential. You can get all the calories and protein you need from real, healthy foods – like the ones we’ve listed below.

Protein powders are a supplement, and they can help you get more protein into your diet, supporting muscle gains. However, they’re just protein rich milk powder and don’t offer any magical benefits that you wouldn’t get from whole milk – they’re just much leaner.

The best way to use protein shakes to gain weight is blending – mixing them with whole milk, whole grains (like oats) and fruit (like bananas) can produce a great homemade weight gainer shake.

Weight gain doesn’t require protein supplements – but they can help improve muscle growth and support that protein dense diet for high metabolism.

How to gain weight with a fast metabolism female

Foods for Gaining Weight with a Fast Metabolism

Gaining weight with a fast metabolism is easier when you use energy dense foods with lots of protein.

Recommended: If you are trying to find the right foods, here is a list of best foods to gain weight with a fast metabolism.

Your meal routine should be built around them. It doesn’t matter if you eat smaller meals more often, or less frequent meals with more calories. Your average intake is most important – muscle gains happen over weeks, not just days.

There are a few ways to gain weight fast – without compromising food quality. You should rely on a few key food groups to make up the bulk of your diet, and then you can experiment with energy dense foods, mass gainers, and other personal preferences on top of these core healthy food choices.

  1. Seafood: rich in protein and healthy fats (especially Omega-3s), fish and seafood are the most important protein source – perfect for the human body and overall health in every way.
  2. Whole grains: a perfect carb source for balanced calorie and nutrient content. Things like oats, brown rice, and whole grain pasta are perfect for adding more carbs and calories to your diet.
  3. Lean meats: with more protein per gram, you’re going to get plenty of muscle building nutrients and have space for more food on the side. Pair with good carbs and veggies.
  4. Beans and pulses: mixed nutrient foods with plenty of protein, carbs, fats, and micronutrients. Any diet should include beans, lentils, and other legumes.
  5. Cultured dairy: rich in protein, healthy fats, and essential micronutrients, these are great choices. Greek yogurt is the most popular, while cottage cheese and hard cheeses both offer plenty of benefits.
  6. Protein shakes: an easy way to get more protein in your diet – and a starting point for home made mass gainer shakes and other high-calorie drinks to beat low-appetite.
  7. Dried fruit (and starchy fruits): dried berries are perfect snacks for weight gain, while starchy fruits (like bananas) offer a simple source of carbs with plenty of extra nutrients.
  8. Milk, fruit juices, and smoothies: you can get extra calories from liquids if you’re struggling to eat enough food or have poor appetite. Easy gains, in moderation.
  9. Homemade protein bars: you can make protein rich bulking bars at home combining simple ingredients – like oats, honey, cocoa, and protein powder. Experiment by preference!
  10. Nut butters: they’re rich in calories and fats, with some protein. Natural nut butters are an easy calorie source, and pair perfectly with other options like shakes, bars, and fruit.

Frequently Asked Questions:

1. Why do I lose weight even when eating a lot?

People with fast metabolism may struggle to gain weight or may even lose weight when eating “a lot of food”. Remember that what counts as a lot is based on your personal calorie spend on average each day, and will vary massively between individuals.

The only real way to tell if you’re eating enough calories is to measure if you’re gaining the weight you want.

If you experience unwanted weight loss, you are not eating enough calories on average. You need to account for your metabolic rate, and a high metabolism just means you need a higher daily calorie intake.

Increase calories and you will see your weight stabilize or increase over a few weeks.

Remember to eat plenty for your own needs and not get distracted by what other people consider a lot, too much, or enough calories.

2. Does a fast metabolism make it hard to gain weight?

Having a fast metabolism – or high metabolism – doesn’t make it hard to gain weight, but it does require more food in a day than someone with a slow metabolism. You may experience unwanted weight loss or stagnating weight gain if you don’t account for your high metabolism.

You will typically also experience more hunger and will be very effective in your strength training, being able to lift heavy weights often.

Your metabolic rate is about the energy required to keep your body healthy and account for activity levels. Make sure your meals and calorie dense foods reflect your high metabolism and account for exercise.

If you’re smart about these simple changes and eat plenty – in a healthy way – you can bulk up with a healthy diet. There’s nothing impossible about gaining weight with fast metabolism – it just requires commitment.

3. How do I slow down my metabolism to gain weight?

You should not slow your metabolism to gain weight – you simply need to eat energy dense foods, or more frequent meals, to improve calorie averages.

Metabolic rate has a lot of factors – many of them important, like immune function and genetic makeup -that you can’t change.

What you can change is the other side of the equation: you can’t reduce calorie needs, but you can increase calorie consumption.

It’s easier to eat more than it is to slow your metabolism, and you’ll gain muscle with more food – especially protein-dense foods.

Your metabolism isn’t a problem – it will slow down with time and aging. What matters is your food intake, and your body burns calories at a rate that it needs.

Eat plenty, and let your metabolism respond to what your intake and recovery demands are – you have a high metabolism for a reason!

4. How many calories should I eat to gain weight?

You can gain weight with any amount of calories that is higher than your body’s energy needs. Typically, the best results come from eating 500 calories more than your TDEE – which means around 3000 calories for most men, and 2500-2800 calories for most women.

The average person maintains their body mass on around 2000-2500 calories per day, and it goes higher with greater activity levels like endurance and strength training.

You can use a calorie calculator to get a rough estimate of your needs – and then work from there based on how your weight responds after a few weeks of consistent eating and protein intake.

Calories for weight gain depend on your age, sex, activity levels, genetics, and daily lifestyle. TDEE is an estimate, and you need to focus on your daily and weekly averages – so don’t get too bogged down in the numbers.

The Mayo foundation offers a good calculator that you can use to get started.

5. What causes fast metabolism?

You can have a fast metabolism because you’re very active, because your body’s still growing, or because you’ve got a genetic tendency to burn more energy. You could also have very high non-exercise activity thermogenesis (NEAT) if you tend to fidget very often or move around a lot during the day.

High metabolism is health-neutral for most people, and is only a problem when trying to gain muscle mass and bulk up. It’s a good thing for weight loss, however, and does have some positives. It’s just that your body is repairing and using energy at a faster rate.

Fast metabolism could be genetic, it could be the result of your lifestyle, or a medical condition (like celiac disease). If you’re experiencing any serious side-effects, consult a doctor and seek medical education and health tips from a professional!

You may also have a very high metabolism if you are particularly muscular, since muscles require a lot of calories to maintain, repair, and grow. This is one of the reasons why lifting heavy weights can drastically increase metabolism, even comparable to cardio exercises.

6. How Do You Boost Metabolism?

Metabolism depends on your genetics, your activity levels, any exercise you do, and the constitution of your body. Muscular people, those with high activity levels or frequent exercise, and young age all boost metabolism – whether you want it or not.

You can boost metabolism by:

  • Eating more protein (which increases the thermic effect of your food)
  • Exercising more regularly, more intensely, or for longer
  • Building more muscle mass – it’s a slow process but has long-lasting effects
  • Increasing your intake of certain compounds, like caffeine, synephrine, or catechols
  • Combatting nutrient deficiency like iodine or chromium – which slow metabolism
  • Addressing sleep deficiency or disruption (which regulates metabolism)
  • Eating fiber-rich foods or addressing medical problems (with medication) to regulate metabolism

There are a lot of ways you can change metabolism, but basic health practices apply to them all. Eat well, sleep well, exercise regularly, and improve the balance of stress and recovery in your life.

Your metabolism needs regulating, and boosting metabolism is only important if you have a slow metabolism already!

Conclusion: How To Gain Weight With a Fast Metabolism

skinny guy

Fast metabolism or not, the same rules of thumb apply to all of us – and you gain weight with a high metabolism by eating more than you burn. Your metabolism burns calories based on the energy it needs, so you need to keep up with it.

If you want to gain healthy weight, that still means eating more calories, more protein, and carbs to fuel your increased needs. If you start to lose weight, you know that you’re dipping too low.

Use your TDEE as a starting point, but don’t forget to adjust based on what happens to the scales!

Focus on protein rich foods, energy dense foods to maintain caloric intake, and avoid dangerous weight loss.

Body mass fluctuates a lot but these simple priorities will help you grow, build muscle, and keep yourself healthy and performing at your best!

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