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You can’t gain weight reliably if you don’t know how your body works. You’re just guessing – hoping to gain weight and build lean muscle mass (this is why we have a solid weight gain calculator).
Our TDEE calculator for calorie intake and muscle mass takes out the guesswork, so you can build muscle mass and get consistent results!
Weight Gain Calculator: What Should Your Calorie Intake Be?
How Do You Use A Weight Gain Calorie Calculator?
You use a TDEE calculator as a starting point for your calorie intake. It tells you how many calories you need to maintain weight. Then you can use this ‘baseline’ to decide how many calories you should eat per day to gain weight or lose weight.
The weight gain calculator says to take your TDEE and add 10-15% to get your weight gain calorie intake. You can go the other way, too, and consume 10-20% fewer calories to lose weight and burn fat.
Getting this right puts you in charge of your weight change and body weight. This is the first step to making your diet work!
How To Lose Weight And Burn Fat: The Basics
For losing weight, eat a lower calorie intake than your maintenance calorie consumption. This is easy by either changing what you eat, or reducing your portions (1).
Most people should reduce calorie consumption by around 10-20% of TDEE to lose weight. You use body fat to make up the difference.
How To Gain Healthy Weight: The Basics
You gain healthy weight when you use a small calorie surplus, around 10% more than your intake to maintain weight. This calorie surplus can be up to 15% for more active people, or slightly higher for fast weight gain.
However, the faster your weight gain, the less healthy weight you will gain. Your body can only build so much lean muscle mass, before it starts gaining extra body fat percentage, too.
TDEE: How To Use TDEE To Gain Weight
You need to use TDEE to estimate your calorie intake and calorie surplus. However, you also need to adjust it to your activity levels, and what changes you see on the weighing scales!
Body weight can respond in odd ways to what you do and what you eat. It’s important to track weight gain every day and focus on your weekly average. This lets you account for how body weight can fluctuate from day to day.
You need to adapt it over time, too, and make sure you calculate again as your weight changes. If you gain weight – 5kg, for example – you need to log that in a calorie calculator to make sure you’re still eating enough.
Disclaimer: Underweight People, Eating Disorders, And Calorie Calculator Use
A calorie calculator can put you in charge of your body weight: but that can be a bad thing. Many people obsess over calorie tracking and counting. It’s important to remember that this is a tool to change your weight gain or weight loss.
It’s not a rigid system, and you shouldn’t use a weight gain calculator to excuse unhealthy practices. Self-watching and eating disorders like orthorexia are common, and you should be self-aware about your relationship with daily calorie intake.
It should be something you use to pursue goals – and not something you feel limited or burdened by.
Consult a doctor or qualified therapist if you have questions about gaining weight in a healthy way, or have a history of eating disorders.
What is the TDEE Formula and How Does it Work?
The TDEE formula is a rough estimate of your calorie needs for one day, based on your resting energy expenditure, your exercise, and your non-exercise activity thermogenesis (NEAT). We use this number as a starting point to set dietary goals and calorie content.
What Goes Into Total Daily Energy Expenditure?
The TDEE formula uses a few key ‘numbers’:
- Basal metabolic rate: the calories consumed keeping your body ‘running’
- Non-exercise activity thermogenesis (NEAT): calories consumed ‘fidgeting’ and moving in general
- Exercise: the deliberate training you perform, calories burned, and post-exercise recovery needs
You also need to consider the Thermic effect of food (TEF). This refers to calories burned digesting food and processing nutrients. Lean meat, for example, has a very high TEF due to the protein content.
These are the factors that contribute to your total daily energy expenditure (2), or TDEE. A weight gain calculator takes these into consideration, but only broadly. Generally speaking, you’ll need to adjust your diet’s calorie content to suit your desired goal.
Things like physical activity can affect healthy individuals, underweight people, and overweight people differently. Health conditions can also adjust these underlying processes.
Where Does Fat Go When You Lose Weight?
When you lose weight and burn fat, fat and other forms of weight are lost through breathing. Most of your weight is lost as carbon dioxide, breathed out during periods of physical activity, and recovery after strength training.
Daily caloric intake needs to be consistently lower than your total daily energy expenditure – so consider daily fluctuations. One day with excess calories won’t ruin anything – it’s about the average.
How Does Your Body Burn Calories?
You burn calories when you eat fewer calories than you need. Your metabolic rate is higher than your calorie intake, and you burn fat to make up the difference. Your body gets those extra calories, burning body fat to get excess calories out that you stored earlier.
Your body burns calories through exercise and maintenance processes. You can increase physical activity to burn more calories, or you can eat fewer calories, and each will shift your energy balance towards fat burning.
How Do You Know How Many Calories You Use Per Day?
Total daily energy expenditure calculators are the best place to start. It’s possible to get a very accurate measurement of your energy expenditure with specialist equipment. However, this is still an estimate but far more expensive and time-consuming.
The TDEE calculator is a new predictive equation to give you the best calorie estimates. These both give you a place to start – and you still need to adjust your intake based on what happens on the scales.
If your daily caloric intake isn’t causing weight gain, measured over weeks, you need to eat more. No predictive equation can make those adjustments for you – so stay aware and adjust to move towards your desired goal weight!
Macronutrients For Weight Gain And Muscle Mass
Total daily calories are an important place to start deciding your macronutrient ratios for weight gain. Good macros help you build lean muscle mass and less fat – the healthy weight gain you need.
You use your total daily energy expenditure to figure out how many calories you should get from healthy fats, carbohydrates, and protein respectively.
Using A Weight Gain Calculator For Macros
For example, if you have a TDEE of 2500 daily calories, you might break down your macros like this:
- Protein: 35% of 2500 – 875 calories, or around 220g
- Carbs: 55% of 2500 – 1250 calories, or around 305g
- Healthy fats: 15% of 2500 – 375 calories, or around 41g
A weight gain calculator lets you start this process and all you have to do is choose foods to fit your calorie and nutrient needs. This makes gaining muscle mass simple, even if you still need to do the hard work of dieting and training!
Frequently Asked Questions
1. How Do I Know How Many Calories To Eat?
That’s what the weight gain calculator does: it provides your TDEE, then you just eat more than that! Take your maintenance calories, and multiply them by 1.1, and start eating that many daily calories.
That’s step one. You can add specific macronutrients or foods afterwards – but you need the right calorie intake, or you’ll never get to your goal weight. Quality of weight comes after you start gaining weight!
2. How Do I Determine My Macronutrient Needs?
Macronutrient ratios depend on activity levels and goals. More physical activity means you need more protein and carbohydrates. Less means you need more healthy fats, fewer calories, and fewer carbohydrates (especially from sugary processed foods!).
We aren’t discussing macronutrients in detail here, but here’s the quick guide:
- Protein: around 35% – more for more activity, fewer for less activity!
- Carbs: depends on your activity levels – more for more active people, very few for sedentary people
- Fats: depends on your activity levels, but the opposite of carbs. More for less activity, fewer for more active people (relatively).
3. How Many Calories Should I Eat A Day To Lose Weight?
To build muscle mass and healthy weight gain, you should eat around 110% of your TDEE per day. Daily calories control what you gain and how much of it – taking it slow keeps your weight gain healthy and improves muscle gains.
Some people can eat around 115% of their TDEE, but this requires lots of physical activity. A mix of strength training and high intensity cardio may be required!
Calories And Healthy Weight Gain Or Loss
Calories are not a measure of health – but the healthy way to gain weight is slow and steady!
A healthy weight gain diet is dependent on a slow weight gain process and healthy foods. This means a lot of protein, vitamins, and minerals – and a lower intake of processed foods. Protein intake controls what you gain, specifically reducing fat and improving muscle building (3).
Fast weight gain comes with an increased risk, making it harder to remain healthy while you bulk up. Healthy weight gain should be built around whole grains, lean meats, healthy fats, and some other calorie-dense favorites like dark chocolate.
The quality of your diet matters – not just the amount of calories!
Exercise for Weight Gain and Weight Loss
You need to exercise to gain weight. It’s the only healthy way to gain weight, turning excess calories into muscle mass. This has 2 sets of benefits at the same time:
- Building muscle mass to improve metabolic health, boost basal metabolic rate, and improve all kinds of healthy risks
- Reducing fat gain to stabilize metabolic health and reduce the risk of cardiorespiratory health conditions.
Exercise is not optional for healthy weight gain or weight loss. It’s an essential part of how and why the body weight changes, and how body composition is determined. The healthy way to gain weight or lose it is to put exercise first and use nutrition to fuel your exercise!
Exercising For Weight Gain
Weight gain exercise should focus on resistance training – either gymnastic strength training or lifting weights. These are the fastest ways to promote muscle growth, which is the best kind of weight gain.
To start with, it’s simple: just try to do more every session or every few sessions. Increase your total workload – either by using new weight, performing more reps, or adding more exercises.
Expanding beyond your current weight is the most popular but unsustainable choice, so focus on building the good habit of patient loading from the start!
Exercising For Weight Loss
Exercise – both resistance and endurance – is an effective tool for weight loss. It’s still essential to resistance train for healthy weight loss, so you keep muscles and bones strong, but cardio drives more fat burning.
Cardio directly increases your calorie consumption and improves the weight you can lose. It also preferentially burns fat, and especially visceral body fat, which has an increased risk for health issues like heart disease!
Eating To Maintain Weight: Body Composition And Performance
Sometimes, you want to eat to maintain weight and improve performance. All healthy individuals will want to maintain weight at some point, and eat a diet that focuses on quality and good habit formation, rather than a desired goal weight.
A healthy diet doesn’t have to be about muscle gain or fat loss.
You can focus on maintaining weight while you build good habits: drinking water more regularly, less drinking alcohol, clinical nutrition goals from a medical professional, or just reducing processed foods!
Conclusion: Understanding Calorie Intake
A weight gain calculator puts you in charge of your diet and lets you move towards a new weight with better muscle mass and body fat percentage. Understanding what your body needs makes the weight gain or weight loss process infinitely easier.
Understand your current weight and how much weight you want to gain or lose – and then tweak a little at a time. If you follow this guidance, you’ll find the weight gain calculator revolutionizes the consistency of your diet.
Come back and check in every 3 months at most, or after gaining weight to calculate calories at your new weight!
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Rohan Arora is a Certified Personal Trainer and Sports Nutritionist and has been actively involved in sports and fitness for over 8 years. He now leads the team of fitness specialists and personal trainers who help people around the world with personalized workout and nutrition plans, along with providing the right information on sports supplements.