How Many Calories Should I Eat?

To kick off our discussion of “diet quantity”, we must first start by building your understanding of calories and metabolism as this will allow you to understand how many calories you should eat. The goal of this whole article series is to walk you through how to actually set up your diet correctly. But I want you to have a skill for life, so in showing you how to set up your diet, I hope to be able to teach you a lot about nutrition and human physiology. 

Understanding calories and metabolism will allow you to have a much better grasp of nutrition, and to be able to make changes to your diet in a much more intelligent manner. Understanding calories and metabolism, at least as it applies to what we want to know about with nutrition, isn’t actually that hard or complicated. It really just comes down to a few basic principles. Understanding these principles will allow you to answer the question of how many calories you should eat, regardless of your specific goals. Understanding the underlying principles rather than learning specific protocols really broadens your understanding and allows you to make much more specific adjustments based on your unique needs.

Before we get stuck in, I would just like to remind you that we offer comprehensive online coaching. So if you need help with your own exercise program or nutrition, don’t hesitate to reach out. If you are a coach (or aspiring coach) and want to learn how to coach nutrition, then consider signing up to our Nutrition Coach Certification course. We do also have an exercise program design course in the works, if you are a coach who wants to learn more about effective program design and how to coach it. We do have other courses available too.

How Many Calories Should I Eat: Calories and Metabolism

To understand calories and answer the question of “how many calories should I eat”, we must first actually understand a little bit more about what makes up metabolism. You see, metabolism gets described as if it is some sort of magical, unquantifiable thing that you either have a “fast one” or a “slow one”, and this really just isn’t the case. Metabolism (in this context) is simply the sum total of all the chemical reactions in the body. Building (anabolism), breaking down (catabolism) and getting rid of waste in the body, all require energy and we can measure this. 

This energy, we call calories. Now, a calorie can be related back to other measures of energy, such as joules. There is a really annoying quirk where the commonly used term “calories” is actually referring to kilocalories and this can be initially confusing as you will see multiple terms thrown around depending on where you read your nutrition information (you may see kilocalories (kC), kilojoules (kJ), calories (C), Joules (J), and potentially even other ones!). I am just going to use the commonly accepted meaning for calories here and throughout this article series.

If you look up the definition of a calorie you will likely find something like this: 

“A calorie is a unit of energy. A calorie is the amount of energy needed to raise the temperature of 1 litre of water by 1 degree Celsius.”

However, this isn’t really all that helpful when we are discussing human nutrition, as we aren’t trying to heat up a litre of water with our food. We are trying to fuel our metabolism (the chemical reactions in the body). So, to understand how to really relate calories back to nutrition, we need to learn a little bit more about metabolism.

When we talk about metabolism, it isn’t the chemical reactions that people are generally talking about, it is the sum of the energy required for those chemical reactions. But we can actually break this number down into smaller categories, based on where that energy is being used in your metabolism. Metabolism can be broken down into the following categories:

• Basal metabolic rate (BMR) (this is the energy you burn at rest, just to keep you alive),
• Non-exercise activity thermogenesis (NEAT) (this is the energy you burn doing all the stuff you do each day that isn’t exercise, such as walking around, fidgeting and so on),
• Exercise activity thermogenesis (EAT) (this is the energy you burn while doing exercise),
• Thermic effect of food (TEF) (this is the energy burned in the breaking down, digesting and assimilating of the food you eat).

All of these energetic values can then be added together and this is your total daily energy expenditure (TDEE). So, for simplicity’s sake, you can think of TDEE and metabolism as the same thing. So when someone says their metabolism is slow or fast, what they are saying is that their TDEE is low (slow metabolism) or high (fast metabolism). This is important to understand because we know what constitutes TDEE and luckily for us, some of this is actually modifiable.

(It should be noted that the system isn’t “perfect” and some heat energy is lost in the processes. This sounds bad, but it is actually a benefit, as it means we can keep our body temperature higher, and this allows us to live in more varied terrains, unlike some “cold-blooded” animals.)

You see, we actually have control over our metabolism to some degree.

Metabolism (and thus TDEE) is a measure of the activity of the chemical reactions in our body, and as a result, bigger humans generally have a bigger TDEE because they simply have more cells, and thus more cellular activity. However, not all cells are equally burning through energy. 

A muscle cell, even at rest, uses more energy just to maintain itself than something like a fat cell, which is mainly just sitting there as stored energy (fat cells do other things too, but we don’t need to discuss this here). 

More cells, also generally means more energy being used. While it isn’t a perfect correlate, body weight is still a good proxy for this, and we can assume that a 100kg person burns more calories each day than a 60kg person (at least as far as BMR goes, or in other words, if each individual just lay in bed all day, the heavier person burns through more energy, especially if more of the weight difference is due to muscle mass rather than fat mass). 

Heavier individuals do also burn more energy for a comparable amount of “non-exercise activity” or “exercise activity”, as moving more weight around requires you to burn more energy. You can test this out by wearing a weight vest while you do your daily activities. You will quickly see that doing your everyday tasks is far more energetically demanding when you wear the weight vest.

Now, this brings up a rather perplexing point to the average person, because generally, you will see bigger individuals complain that they have a slow metabolism, while smaller individuals complain that they have a fast metabolism. However, in reality, this usually isn’t actually the case, and it is actually generally reversed. This is really just semantics, but it does actually helps you to understand metabolism better if you get this straight in your head. 

It is also important to realise that body weight is just a proxy for what we want to know, and the composition of the weight does actually influence energy expenditure too. Just because you weigh the same as someone else, this doesn’t mean you will burn the same calories each day, even if you do pretty much the exact same stuff each day. 

If someone is the same weight as you, but they are 10% body fat, and you are 30% body fat, they are likely burning more calories even at rest, as muscle is more energetically costly to maintain than fat. 

So the common way of thinking about slow and fast metabolisms is correct if you are the same weight but have different body fat levels. In this example, the leaner individual will (likely) have a “fast” metabolism (high TDEE) and the fatter individual will (likely) have a “slow” metabolism (low TDEE) despite them both weighing the same. This is because the leaner individual has more lean mass (often called fat-free mass). To compare individuals, you have to correct for lean mass, and when you do this, you very often see that each individual kilo of lean mass is pretty much identical between individuals (there is some variance though). 

You can work out your body fat with our body fat calculator and you can work out your fat free mass with our FFMI calculator.

The difference we may see between individuals is down to the fact that some individuals just have more lean mass than others, despite weighing the same weight (i.e. they have more muscle and less fat). 

However, this is rarely the stuff that we actually care about in the real world. It is important to understand that being more muscular and leaner is a modifiable part of the metabolism, and most people should likely aim to get a bit leaner and build some more muscle if they want to optimise their metabolism. But it is important to realise that this isn’t the main driver of differences between individuals. 

The stuff that really makes the difference between individuals is NEAT and EAT. Some people just move much more each day than others. They have higher step counts (which is a good proxy for NEAT) and they exercise multiple times per week (EAT). That is where the vast majority of difference actually occurs, and where your attention should be, and I will bring this back up when we discuss “calories in vs calories out” (CICO).

Just to round things out, there is some difference in terms of the TEF depending on the food choices we make. High protein and high fibre foods generally require more energy to break down and digest, and as such have a higher TEF and this has a small impact on TDEE. So it makes sense to eat more protein, fruits and vegetables if (among other things) you want your metabolism to be ticking along nicely!

Now, it is also important to understand that metabolism is adaptive and it isn’t just a fixed number. If you eat less, your metabolism will go down (as TEF, NEAT and BMR (due to lean mass loss) will all go down) and if you eat more, your metabolism will go up (as TEF, NEAT and BMR (due to lean mass gain) will all go up). This is a normal part of metabolism, and it isn’t anything to worry about. 

Despite what you may hear, you can’t break your metabolism. This adaptive nature of the metabolism is an evolutionarily conserved advantage, so you don’t starve to death during periods of famine. 

You will also see sex hormone changes too, in response to the diet, and this is part of the same phenomenon. It isn’t usually a good idea to be pregnant during a famine, so sex hormones do go down when calories are low. This can more easily be seen in women, as they tend to have more adaptive metabolisms, and they will lose their menstrual cycle (and thus be transiently functionally infertile) if calories go too low or for too long. Men will still get lowered sex hormones, but as they don’t have a menstrual cycle, this is less obvious and usually first presents itself as lowered sex drive (although this is also the case in women). 

However, it must also be understood that it is different in different people, and some will see more adaptation than others. The sex hormone stuff is part of the BMR category of metabolism, for those wondering.

Further to this, metabolism isn’t completely additive either, and instead it is constrained. What I mean by this is that while it may seem to be the case that if you just keep doing more and more exercise (EAT), you will be able to burn an indefinite amount of calories (an additive system). However, in reality, it seems to be a somewhat constrained system, where doing more exercise will usually just result in lowered BMR and NEAT to compensate (this is usually seen over a longer period of time than just a single day, whereby you do a lot of activity one day and then the subsequent days you see reductions to BMR and NEAT). 

This is potentially another evolutionarily conserved adaptation both due to a limit on the amount of nutrients the digestive system can absorb, and a system designed to stop you from exercising yourself to death. However, this constrained nature of metabolism is rarely a concern for people, and really only matters for athletes who are training for hours upon hours each day. 

While you will see people try to use this information to say you can’t exercise to lose weight, this is simply not the case. The average person is unlikely to exercise enough for this to be a concern and even if it was, overcoming this is usually as simple as ensuring that NEAT doesn’t drop too much. This can be done surprisingly easily by ensuring you keep your daily step count high.

Now, that was a slight bit of a detour from discussing calories directly, but it was necessary to iron out those few things before we get stuck into the main thing you need to understand the foundational component of all diets. This is the concept of “calories in vs calories out” (CICO) that I mentioned earlier.

Calories In, Calories Out (CICO)

What CICO is describing is the broad equation that describes the relationship between your metabolism, the calories you consume and your body weight.

If you eat the same amount of calories (calories in) that you expend (calories out), your body weight will remain the same. This can (and should) be viewed over a larger time course than just a day, but if your daily/weekly/monthly/yearly calorie intake matches your daily/weekly/monthly/yearly calorie output, you will remain roughly the same body weight (there will still be some fluctuations due to water weight, food in your digestive system etc.). 

There are some cases where this doesn’t hold perfectly true, but this is mostly at the extremes of timescales (i.e. if you didn’t eat anything for a year and then ate all the food in one day, your body weight wouldn’t remain the same, because you would die trying to do that), and in practice, it is 100% accurate when we look at things on the daily/weekly/monthly scale and assume you are eating at least the bare minimum to survive each day.

If you consume more calories (calories in) than you expend (calories out), your body weight will trend upward over time. Again, there are some extremes where this doesn’t hold true, notably if you try to eat the vast majority of the calories for a week (or longer) in a short period of time, as you will likely not actually digest and absorb these calories. For example, this happens when people do those 10,000 or 20,000 calorie challenges you see online, as these individuals reach the limit of their digestion and don’t digest a lot of the food, either vomiting it up or pooping it out relatively undigested.

If you consume fewer calories (calories in) than you expend (calories out), your body weight will trend downward over time. Again, there are some caveats here, but of all of the three possible scenarios, this is actually the one with the least exceptions to the rule.

Earlier on I discussed a situation where someone is said to have a fast or slow metabolism, and in reality, the issue is usually that the person with the fast metabolism simply consumes less food over a time given time period, and likely also moves more, than someone with a slow metabolism. Most fat gain occurs over years, not swiftly over a few days or weeks, and thus you can’t compare two individuals on a week of data alone. Averages over time are what matter.

Now, how do we use all that information to actually design our diets?

Well, we want to find out how many calories we need to consume to maintain our current body weight. You may want weight loss or weight gain, but the first step is to find out what calories will cause weight maintenance, as this does actually make things much simpler in the long run.

Weight Maintenance

You can find out your maintenance calories in two ways. The calculator method or the “average and adjust” method. To most people, the calculator method seems more scientific, but the average and adjust method is actually usually better in practice.

The calculator method involves using one of the many calorie maintenance calculations that have been devised. For example, you could use the Harris-Benedict calculation, which would involve the following:

Metric Harris-Benedict for Men

BMR = 66.5 + ( 13.75 × weight in kg ) + ( 5.003 × height in cm ) – ( 6.755 × age in years )

Metric Harris-Benedict for Women

BMR = 655.1 + ( 9.563 × weight in kg ) + ( 1.850 × height in cm ) – ( 4.676 × age in years )

You would then use this figure and multiply it by an activity multiplier to account for the previously discussed NEAT and EAT. The multipliers are as follows:

• Little to no exercise: Daily kiloCalories needed = BMR x 1.2
• Light exercise (1–3 days per week): Daily kiloCalories needed = BMR x 1.375
• Moderate exercise (3–5 days per week): Daily kiloCalories needed = BMR x 1.55
• Heavy exercise (6–7 days per week): Daily kiloCalories needed = BMR x 1.725
• Very heavy exercise (twice per day, intense workouts): Daily kiloCalories needed = BMR x 1.9

This will give you a rough idea of where your maintenance calories are at. However, this number isn’t infallible and you will still have to see how your body responds in the real world after you actually eat that amount of calories consistently. You can use our calorie and macronutrient calculator to work out your calories for you if you don’t want to do the maths yourself. 

To do the average and adjust method you need to keep a food diary (most people just use an app like MyFitnessPal for this) for a week (ideally 2 weeks), and quite literally log everything you ingest (including liquid calories, and “bites” of food). 

Now the tricky thing is, ideally, you would eat as you normally would, as this will give you an idea of where the diet has been and make the process of figuring out maintenance calories easier. However, even with you trying your hardest to eat “normally”, you will likely still adjust your caloric intake by virtue of just being more aware of it because you are now tracking. 

Now, along with tracking your food intake, we also recommend tracking your body weight first thing in the morning. Changes in your body weight will allow us to see if the calories you are eating are putting you in a surplus (weight gain) or a deficit (weight loss). At the end of the week of tracking, total up the calories from each of the 7 days and divide that number by 7, to get your average daily calorie intake. But also make a note of how your weight has changed in this period. 

We do actually learn a lot if your weight has reduced or you have gained weight, as we can estimate how your daily average intake has affected your body. If you gained weight, we know you are eating a surplus of the calories required to maintain your body weight. Alternatively, if you lost weight, we know you are eating fewer calories than are required to maintain your body weight.

It requires roughly a surplus/deficit of 7,000 to 9,000 Calories to gain/lose 1kg of body fat. Utilising this knowledge we can make an educated guess as to what your maintenance calories are. I say educated guess because it isn’t really that simple and the body does a lot of strange things, especially in relation to water balance that makes accurately correlating weight to calories a very difficult task. 

If you gained 200g in the week eating your normal diet that means you were roughly in a surplus of ~1540 calories over the 7 days, conversely, if you lost 500g you would have been in a deficit of 3850 calories for that week (using 7700 as the number of calories required to lose/gain 1kg). From this, you can work out roughly where you are in relation to your maintenance calorie needs. Although it isn’t a very precise method it is actually more accurate than the calculator method, because it actually takes into account you as an individual and isn’t just a theoretical average. 

Eating where you now think your maintenance calories are, you can see how it affects your weight. If you are eating “at maintenance”, and you noticed a decrease or increase in weight over time, you may need to make adjustments to what you think is your maintenance calories. To do this you would simply reduce your daily calorie intake by 100-200 calories if you gained weight, or increase by 100-200 calories if you lost weight. 

This will allow you to really dial in to where your maintenance calories are. This is a crucial step, as it really does make either losing or gaining weight so much easier. It takes a lot of guesswork out of the system, and it allows you to be much more precise with your nutrition. 

Unfortunately, a lot of people skip this step and just go straight into trying to gain or lose weight. But if you can spend a little bit of time really dialling in your maintenance calories, it really does make a big difference. 

It is also helpful to spend some time eating at maintenance as you can actually build some good food habits while eating at maintenance. It is much harder to build good food habits if you are also dealing with excessive hunger or cravings because you are in an aggressive deficit. 

Weight Loss

If your goal is weight loss and you now have a rough idea of your maintenance calorie intake, then eating at a roughly 10-15% calorie deficit will allow you to lose fat slowly while remaining healthy and performing well. For most people, this will be somewhere in the range of a 200-500 calorie deficit. 

There is an urge to immediately drop calories drastically (by some arbitrary number like 500 or 1000) but this will generally lead to poor performance, poor health, bad adherence, and poor long-term results. We want to optimise your health, performance and body composition, and being too aggressive doesn’t allow us to do this. By actually fuelling the body (even in a deficit) you will be able to build (or maintain more) muscle and strength while you lose body fat, and you will feel much better than if you were eating low calories. 

You want to try and diet on as many calories as possible. Don’t get caught in this race to the bottom, where you try to drop calories lower and lower. Instead, try to keep calories as high as you can while still achieving your goals. You will get better results, and you will enjoy the process way more. You will also be far more likely to actually stick to the diet this way too, and consistency and adherence are the biggest factors in achieving results. 

We can get a bit more specific than just saying eat a 10-15% deficit, and we can set our deficit based on our desired rate of loss. As a very rough and ready rule, a 0.5-1% drop in body weight per week would be considered a good rate of fat loss. We should also note that, just because in our head it is handy to use the 7-day Gregorian Calendar as our gauge, doesn’t mean that the body works on a 7-day calendar. We need to look at the diet over longer time periods, and not view it purely on a week-to-week basis.

For example:

Week 1 2.5% body weight drop

Week 2 0.5% body weight drop

Week 3 0.5% body weight drop

Week 4 0.5% body weight drop

… and …

Week 1 1% body weight drop

Week 2 1% body weight drop

Week 3 1% body weight drop

Week 4 1% body weight drop

…equal the same rate of fat loss when looked at on a monthly scale. However, the first example when compared on a week-to-week basis with the second may look like they are making less progress, despite their monthly rate of fat loss being EXACTLY the same.

So think big picture.

When averaged over a few weeks, an average rate of fat loss of 0.5-1% is our rough recommendation. Although faster and slower rates do occur we find this to be the sweet spot. Remember it is the general trend in fat loss we are looking at. One bad day or week isn’t going to ruin progress, it may simply slow it down momentarily.

If we are looking for somewhere in the range of 0.5-1% bodyweight drop per week during our fat loss phase, you should actually work this out and see what that actually means for you. Just get your body weight and divide it by 100 to get 1%, or 200 to get 0.5%. 

Now that you have an idea of how much you should be losing, you can work backwards and create a deficit based on that. If the rate of fat loss desired is 1kg per week, then you are going to have to eat at a weekly deficit of roughly ~7,700 calories (a rough figure for losing 1kg of fat). Which translates to a ~1,100 calorie deficit per day.

But let’s work this out on some actual real-world examples to make it much clearer.

• 100kg individual, rate of fat loss 0.5kg to 1kg (0.5-1%) per week, calorie deficit 550 to 1100 per day.
• 80kg individual, rate of fat loss 0.4kg to 0.8kg (0.5-1%) per week, calorie deficit 440 to 880 per day.
• 60kg individual, rate of fat loss 0.3kg to 0.6kg (0.5-1%) per week, calorie deficit 330 to 660 per day.

Now, this is not to say you have to lose fat at these rates. You will likely also notice bodyweight drops quite fast in the first week or two on a diet, and this is purely due to a drop in muscle glycogen and water (and maybe less food in the digestive tract). 

So the first one to two weeks of dieting it is always hard to judge whether you are in the correct deficit or not. But you should be trending towards a drop of ~0.5-1% body weight per week, or whatever your preferred percentage drop is. 

Again, you can go faster than this, but we need to factor in whether even losing at 1% is actually sustainable for you. If it is your first time dieting I would caution you to use the lower end of the range, as you will likely encounter some issues as you diet and make a few mistakes along the way. There is no reason to make the diet harder with a steeper calorie deficit, if you haven’t already got a firm base of counting calories/staying on plan. If you eat a big deficit, the likelihood that you will binge is much higher. So do keep sustainability in mind.

This is similar for smaller women or guys who maintain their weight on lower calories. If you somehow worked out 1500 as your maintenance, and I am suggesting a 660-calorie deficit, eating 840 calories per day is obviously highly unsustainable. In this case, you would be much better served to keep your calories high, by both aiming for a much slower rate of loss, and trying to increase your activity. If calories are that low as maintenance, you are likely not very active or you are just a smaller individual to begin with, which would make me more inclined to suggest dieting slower as a general rule.

This brings me to my next point which is that you don’t always have to eat less to lose weight. If you are eating at your maintenance, you can induce a calorie deficit by increasing your activity levels. You can induce a calorie deficit by introducing some exercise, especially cardio exercise into the routine. A 500-calorie deficit is still a 500-calorie deficit if you eat 500 calories less or you do 500 calories more activity. You can also do a combination of both. 

There are differences in some of the adaptations you get, but from a thermodynamics perspective, it is still all calories. You do get increased mitochondrial biogenesis from doing more cardio, which potentially allows you to lose fat more easily. But it is likely a very small difference. You do also burn some more calories after you finish exercising, which you wouldn’t burn from just eating less, not to mention you likely are more active if you are making your way to the gym to exercise. However, the overall difference isn’t likely all that big. 

When you are adding cardio to your routine, you should be tracking the calories you burn in that session rather than just time doing cardio. Tracking time is a pretty useless metric with regard to using cardio for fat loss. All these people doing an hour of cardio could have a huge variance in how many calories they burn during that hour. So when tracking cardio for weight loss, track calories not time. It isn’t perfect, but it is a better standardisation than time, especially if you are using something like a fitness tracking watch that is calibrated to your weight.

Standardising your NEAT as best you can is also a surefire way to stop you from running into those negative metabolic adaptations that accompany dieting. We like a target of over 10,000 steps per day, but the target itself is arbitrary, it could be 9,000 it could be 20,000. You just have to be consistent with it. I wouldn’t even think about adding cardio if you are not already accounting for steps. You will burn extra calories doing cardio, but you will just down-regulate your NEAT for the rest of the day if you don’t actively account for it. 

There are also some pretty substantial health benefits to having a high daily step count, which we discussed in our article on the exercise guidelines. 

So to summarise this segment, create a deficit of calories that leads to a loss of ~0.5-1% body weight per week either reducing calories from maintenance or doing more cardio to make up the deficit. This should be adjusted based on real-world outcomes. The first one to two weeks are the hardest to gauge progress as you will lose water and glycogen, but overall you should be able to see if you are losing at the rates we prescribe. This is of course as long as you are consistent with tracking. There is literally zero point in being in a deficit Monday to Friday and binge eating on Saturday and Sunday. We want consistency across the whole week.

Weight Gain 

If your goal is weight gain and you have a rough idea of your maintenance calorie intake, then eating at a 5-10% calorie surplus will allow you to gain muscle slowly, while minimising fat gains. For most, this will be in the range of a 100-300 calorie surplus. As with fat loss, there is an urge to make drastic calorie increases (500+ calories) but this will just lead to unnecessary fat gain and won’t enhance your muscle-gaining abilities more than a slight increase in calories will. You can’t force feed muscle gain.

In general, the most genetically gifted for muscle gain are probably still gaining less than 1kg of muscle per month, and as such, you probably don’t want to be gaining much more than 1kg of body weight per month, as a higher and higher percentage of that gain will simply be fat gain. The more advanced you get, the less return on investment you will get too. 

In general, most men are going to get the best results by aiming to gain somewhere between 0.5-1kg of body weight per month, and women will get the best results by aiming for about half of that (0.25-0.5kg per month). As you get more advanced, expect a smaller and smaller monthly weight gain.

Body Recomposition 

There is another option, and it’s not really something that people talk about because it is super, super slow and it’s not really optimal. You see, technically speaking, you can gain muscle and lose fat at the same time, and muscle can be gained in both a deficit and at maintenance. However, these scenarios are generally not optimal. 

But for the sake of those who want to maintain roughly the same weight they are currently at and just want to super slowly gain some muscle and drop some body fat, we will cover this option. If your goal is body recomposition and you have a rough idea of your maintenance calorie intake, then you have three options. 

You can eat:

• at this level (maintenance calories), 
• 3-5% below this level (if you want to favour fat loss a little more), 
• or 1-3% above this level (if you want to favour muscle gain a little more). 

These options will allow you to very roughly maintain your weight, while very slowly adding muscle and reducing body fat. But this option is just incredibly slow and in the real world, you would simply be better off just fully committing to weight loss or weight gain if either of them is your goal. Practically speaking, eating a very small surplus or deficit is incredibly tedious and realistically there is already a large degree of error involved with calorie tracking that trying to eat in this manner is just a very low return on investment.

Making Calorie Adjustments 

The hardest part about any diet is knowing when to make adjustments. People either become too trigger-happy and feel they must make adjustments every week to see continued progress, or people stay on the same calories for too long when progress has stalled. Just because you have spent a lot of time working out your maintenance calories and you have been diligent with your diet, that doesn’t mean everything will run perfectly smoothly with your progress. 

There will be ups and downs, and you will eventually (more than likely) stall (and this is entirely normal in the presence of body weight change, as energy expenditure scales up and down with those changes).

So how do you know when to make adjustments? And what adjustments should we make?

Firstly, as we have discussed previously, your diet should be outcome-based. If you aren’t achieving the outcome you want then something must change. However, before you wake up and decide one day that you aren’t achieving the outcome you want, you must consider the bigger picture.

If you are consistently losing 1kg per week and then one week you only lose 0.5kg, that doesn’t necessarily mean you need to make any changes. We are looking for the overall trend in weight loss or weight gain, combined with the feedback from the mirror. Generally, we don’t make adjustments unless you have stalled for 2-4 weeks weight-wise (especially if you are a woman and have a menstrual cycle also affecting body weight).

We also tend to prefer very minor tweaks to the diet. Just because weight loss or weight gain has stalled, doesn’t mean you have to reduce or increase calories by 500-1000! Small changes in the range of 100-300 tend to yield the best results, as you are able to diet on higher calories, performance is better and adherence is generally also much better.

Generally, we like calorie increases to come from carbohydrates, although based on your preferences and overall calories, the increase could come from fats. We generally like calorie decreases to come from fats (but rarely would we suggest dropping below ~0.5 grams per kilogram of body weight, and we will discuss macronutrients more in-depth in the next few articles in this series). Keeping carbohydrates high while dieting will allow you to keep your physical performance high, while also allowing you to eat a larger volume of food (as 1 gram of carbohydrates has 4 calories, while 1 gram of fat has 9 calories), especially if you choose mostly whole foods like we recommend.

So if you have stalled for more than two weeks, dropping or increasing calories by 100-300 based on your overall calorie intake and goals will ensure you continue losing or gaining.

Measuring Success 

Now, even though we have just spent ages talking about how the scales should be moving in accordance with your goals, in response to your diet and training, we actually don’t believe the scales is all that important. 

It literally only tells you your relationship with gravity. 

You see, if you drink more water one day, the scales will go up. Weigh yourself later in the day, the scales will be up. Didn’t eat much vegetables/fibre the last few days, weight will be down. Haven’t gone to the bathroom for a while, scales will be up. So scale weight is highly variable, and shouldn’t be your sole measure of success.

As a result, with our coaching clients, we like a combination of:

• scale weight, 
• progress pictures (we highly recommend you take these weekly as you will really wish you did once you have lost fat and/or gained muscle, and they really are a great way to measure progress when other metrics are changing that much), 
• the mirror, 
• how clothes feel on you,
• and finally a tape measurement of the waist (and potentially other body parts). 

If you keep track of all these things you are guaranteed to find a metric that is changing over time. From this, we can make the necessary adjustments. Consistency in your measurements is required for them to be accurate, however. 

The more times you measure per week the more data points you will have, but daily measurements can really mess with some people’s heads. So you may need to measure less frequently. 

Regardless of the exact schedule, you should aim to standardise the schedule and circumstances of the measurements as best you can (for example, always do your weigh-ins in the morning after you have gone to the toilet, as it isn’t accurate to compare them to night time measurements after a full day of food and drink).

Calorie Distribution

Before we finish up this article, we do need to touch on the topic of calorie distribution. There are some nuances around how you actually spread your calories out across the day that are important to understand as it does influence how you set up your diet and then actually implement the diet. There is also a lot of noise on the internet with this stuff, and we can relatively quickly cut through that and get a clean signal.

In general, we recommend that calories should be relatively evenly spread throughout the day. Most people will sleep for ~8 hours, and that means you will have a 16-hour feeding window each day. Now most of you are simply not eating from the second you wake up until the second you go to sleep, so this isn’t exactly a perfect 16 hours, but you get the idea. We have roughly 16 hours to distribute our food across the day.

However, what most people do is distribute the vast majority of calories towards the evening. They have a light breakfast (or skip it), maybe a medium-sized lunch, and then they have a big dinner and usually some extra snacks/food after dinner too. So the food distribution across the day is heavily biased towards the later half of the 16 hours we have in our feeding window. Unfortunately, research would seem to suggest that this is actually one of the less healthy ways to distribute our calories.

There is a field of research called “chrono-nutrition” which researches how nutrition and our circadian rhythm (basically our body’s internal body clock) interact. To (almost comically) distil an expansive research base down to a few words, research in this area suggests that eating more of your food later in the day isn’t optimal from a health perspective and has many ill effects ranging from an increased risk for cardiovascular disease, metabolic disease and even some cancers.

Now, there are actually quite a lot of complex interactions going on here, both with circadian rhythm (and its disruption) affecting eating patterns and eating patterns affecting circadian rhythms, but again, for this discussion, the nuances aren’t all that important. We want to know what to do.

What the research in this area seems to suggest is that spreading your intake out throughout the day, and potentially even biasing more calorie consumption to the earlier part of the day, may be the best option for health, performance, satiety and potentially also body composition. Even if you can’t or don’t want to spread your intake out more evenly, the research in the field of chrononutrition and the research in the field of sleep science would seem to suggest that you should ideally leave some time between your last meal and the time you go to sleep. Something like 2-3 hours seems to be what works and is most practical for most people, which means if you go to sleep at 11 pm, you would have your last meal at 8 pm or 9 pm.

Eating in this way means you are left with a rough eating window of 13-14 hours, from when you wake up, to roughly 2-3 hours before you go to sleep (we discuss this all more in the sleep article). Within that window, you want to spread your intake out relatively evenly, potentially even biasing higher calorie intakes to earlier in the day.

Now, having coached a lot of people, the most frequent objection to this is people saying they just aren’t hungry in the morning. To be fair, some people are just not hungry in the mornings and they may just do better with allocating more of their food to later in the day (by later I mean towards the middle of the day, not necessarily to the end of the day/feeding window).

However, in most cases, the reason people say they are not hungry in the morning is because they have eaten a lot of food late in the evening the night before, or they are just very highly stressed in the morning (which can blunt hunger). People also often mask their hunger by taking stimulants like caffeine, which can also blunt hunger.

If you reduce the stress in the morning by doing stuff like going to bed a bit earlier, not having 30 alarms wake you up, having things prepared and ready to go so you aren’t rushing around the house looking for things in the morning, not looking at your work emails or social media first thing upon waking, not hammering down huge quantities of stimulants (i.e. coffee) and any other things you can do to lower morning stress, and then you combine this with not eating 2-3 hours before bed, and in almost every single case, morning appetite returns.

As I have seen this play out time and time again with my coaching clients, I know that a large portion of you reading this (to who this information directly applies), will simply think, “Nah, that isn’t me” or “Nah, I can’t possibly reduce morning stress because of X, Y, Z”, and while that may actually be the case, for most of you, it isn’t, and you would actually do a lot better if you did actually spread your calories out a bit more and eat in the morning.

However, even if you can’t fully buy in to this, you can still improve things by more evenly spreading your calories across your own eating window, not saving the majority of your calories for the evening, and trying to keep 2-3 hours before bed a food free period. Basically, we just want a more even spread of things, rather than the extreme evening bias with calorie distribution that most people do.

Time Restricted Feeding (TRF)

Now, you may be wondering about protocols like time-restricted feeding (TRF), where you decrease your eating window to something like 8 hours instead of 16 hours. This is often called intermittent fasting, although that is technically something different (and we will discuss it in a moment). There are actually a variety of protocols out there for intermittent fasting, however, most of them are set up to continue the fasting period (the non-feeding window) further into the day. So with something like a 16-hour fasting window, you would stop eating at 9 pm at night and then not eat again until 1 pm the next day.

I know all of you out there who identified with the “not hungry in the morning” discussion in the previous paragraph are foaming at the mouth now, and love to hear that there is an actual name for what you have been doing! However, the research on these types of diets still generally shows that biasing your eating window to earlier in the day, rather than later (often discussed as early TRF and delayed TRF in the research) is better and almost every protocol still has people not eating 2-3 hours before sleep.

There may be some benefits to TRF, but this usually revolves around getting people to eat fewer calories (simply by having a cut-off for eating rather than allowing people to eat all day people eat fewer calories). I am not convinced that the benefits are all that much better than just having a relatively even distribution of calories across the waking day, while also having 2-3 hours before bed as a food-free period. There is research ongoing in this area, but unfortunately, TRF with the majority of calories biased towards the later half of the day, especially if there is a high-calorie intake close to sleep, don’t seem to be optimal for health (again, I will refer you to the sleep article for an expanded discussion).

While TRF protocols can be a tool in the toolbox, especially for those of you who are on low calories, they are not a magic bullet and they shouldn’t be used as a tool to just allow you to get away with poor diet habits. You will, unfortunately, see this very often in the fitness industry, as people who are on low calories save up large amounts of their calories for the end of the day, and to do this, they effectively just don’t eat all day and call it “intermittent fasting”. It is very often just disordered eating patterns, and these people very often just have very poor relationships with food in general. It is understandable to want to bias calories towards the evening and to come up with protocols that allow that, as a lot of the “fun” foods that people want to eat are seen as dinner foods or desert foods, and this is even more attractive if you have fallen into the habit of always having lots of “treats” in the evening (as an aside, this desire to treat yourself in the evening usually also resolves itself when you more evenly spread calories across the day, as you aren’t starving and feeling restricted all day), however, it isn’t an optimal practice and we would not recommend it as your baseline diet structure.

Calorie Intake Around Exercise

Now, the only thing that further modifies how we distribute our calories across the day is exercise (for all things exercise, you can visit the exercise hub). While we generally want to relatively evenly spread our calories across the day, we may want to also bias some more calories around exercise. This doesn’t have to be excessive, but it does make sense to ensure you are well fuelled for exercise (so calories biased before exercise) and that you recover from exercise effectively (so calories biased after exercise).

Now, as I said, this doesn’t need to be excessive, but it is something that should be on your radar. It isn’t always possible, especially if you train first thing in the morning (most people aren’t going to get up 1-2 hours before their 6 am training session just so they can get a meal in, and we certainly wouldn’t recommend that, in general). However, we can still have a general rule in place that suggests we try to ensure we are well-fuelled before and after training.

This obviously becomes more important the more serious or advanced your training is (i.e. there is a difference between how important this would be for those of you who are trying to perform at the highest level versus those of you who want to train for general health and fitness) and it also becomes a bigger concern if you are training multiple times per day (because you need to make sure you are well fuelled each session and recover as much as possible between each session).

So we want to relatively evenly distribute our calories across the day, but have a slight bit more around when we train. This can be a bit difficult if you train very close to bedtime, but most people are not generally training within 1-2 hours of sleep anyway (as it generally causes people not to be able to get to sleep easily), so it is less of a concern.

Weekly Calories

Finally, while we have been discussing calorie distribution across the day, we can also think about this across the week. You see, there is no reason to only think of calories across a single day, and realistically, it is better to think of things on a longer time scale. What you do on average, is the thing that matters most. So theoretically, you could spread your calories across the week disproportionately (i.e. some days higher, some days lower) and once you are in and around the average level of calories you need to be for any given day then you will move towards your goal, especially if you are only concerned about body composition (i.e. you need to eat 2000 calories per day, that is 14,000 calories per week, so you could eat 1500 for 5 days and 3250 on the 6th and 7th day and still be eating 2000 calories on average for that week).

This is somewhat true, and it is probably best to think of things on average, as some days are going to be slightly above or below your calorie targets. However, people very often run into trouble with this thought process and try to “save” calories for the weekend, and starve themselves Monday to Friday to do so.

This generally doesn’t lead to the best results (as you are under-fuelled most of the time, and even if you are losing fat, you are likely losing muscle and your performance (in the gym and in life) is probably not optimal either), and more often than not, it just leads people to binge eat. The binge eating either happens midweek (i.e. by Wednesday you end up starving at eating way more than 1500 calories), or it occurs on the weekend itself (i.e. you think you are only going to eat 3250 on Saturday and Sunday, but you end up eating way more because you have felt so restricted all week, you simply can’t stop yourself once the brakes are off).

So in theory, yeah, you can view things on a longer time scale than a single day, but this only works when the calorie differences are actually quite small (i.e. 100-200 for a given day), and for some people, it isn’t worth it to try, as they will actually just end up with a worse relationship with food.

Somewhat related to this is calorie cycling, where you alternate various calorie levels across the week. So you may have certain days as higher calorie days, some days as medium calorie days and other days as low-calorie days. A more extreme form of this would be intermittent fasting where you simply don’t eat (or consume very little food) on some days. There are potential benefits to cycling calories across the week, and certain protocols are set up more intelligently than others. However, this concept oftentimes just makes dieting more complicated. It can be helpful for people with days with very high-calorie output (such as athletes with very high training volumes or manual labourers), but similarly to what we discussed about viewing things on a scale longer than 24 hours, there isn’t a massive benefit to calorie cycling versus just eating relatively consistently across the week.

Small differences can make sense, but eating in a deficit a few days per week and then eating in a surplus on other days isn’t going to make you lose fat and build muscle, the average is what matters. There may be some benefits, in certain circumstances, but in general, these approaches generally just make building consistent and sustainable diet structures harder, not easier. It is very easy to fall into the trap of thinking there is some massive benefit to calorie cycling, but as a thought experiment, if you simply count your days from midday to midday rather than midnight to midnight, the calorie distribution of many of these calorie cycling approaches simply cease to make any sense and you will quickly realise that it is average calorie intake that matters the most.

There are potential benefits to fasting, but a surprising amount of these benefits can simply be achieved via calorie restriction itself. It doesn’t have to be “no calories”, it just has to be “less calories”. Some people may need a bigger signal to gain benefits (i.e. the deficit needs to be larger), but most people will get a lot of the benefits that are often touted for fasting by virtue of eating a calorie deficit for a period of time. Some populations may benefit from periods of no food intake, such as may be suggested with true intermittent fasting (protocols such as 5:2 where you don’t eat, or eat very little 2 days each week). However, this is usually because it allows for better adherence to a larger deficit, which may be necessary for time-sensitive medical issues (such as rapidly reducing organ fat deposits in people with the early stages of type 2 diabetes) rather than any unique benefits to fasting itself.

To summarise the information about calorie distribution; it makes sense to relatively evenly spread your calorie intake out across the day, potentially biasing intake earlier in the day and around exercise, and ideally stopping food intake 2-3 hours before sleep. If you can do that on most of your days you will be in a very good place with the diet in general (there are always going to be situations like meals out, parties, celebrations etc that disrupt this). While there are potentially some situations where we might need to fine-tune calorie distribution across the day, this generally only applies to athletes who are training multiple times per day and are looking to maximise their performance in each session.

How Many Calories Should You Eat Conclusion 

What we’ve learned so far leads us to some very simple rules about calories by which weight loss and weight gain can be explained. These rules are absolutely fundamental to determining how much you weigh.

• If you burn more calories than you eat you will lose weight. 
• If you eat the same amount of calories that you burn your weight will not change. 
• If you eat more calories than you burn you will gain weight. 

When trying to set up a diet, you want to work out your maintenance calories either using a calorie calculator or the average and adjust method, and then depending on your goals, make a small adjustment up or down in calories to that you are losing/gaining at an appropriate rate. 

As we are dealing with a complex system (metabolism), we don’t want to be too aggressive with our calorie increases/decreases, and we also want to try and control as many of the variables as we can (it is especially important to try to control for NEAT, thus we recommend setting a daily step target).

In general, you want to ideally spread your calorie intake out across the day, potentially biasing more calories earlier in the day and perhaps also around your workouts.

If you want to really optimise your diet and tailor it to your specific goals, we can help you do this. You can reach out to us and get online coaching, or alternatively, you can interact with our free content. This article series will show you the basics of how to dial in your nutrition, but if you have specific goals, you will generally need a more specific approach to the diet.

If you want more free information on nutrition, you can follow us on Instagram, YouTube or listen to the podcast, where we discuss all the little intricacies of exercise and nutrition. You can always stay up to date with our latest content by subscribing to our newsletter.

Finally, if you want to learn how to coach nutrition, then consider our Nutrition Coach Certification course, and if you want to learn to get better at exercise program design, then consider our course on exercise program design. We do have other courses available too. If you don’t understand something, or you just need clarification, you can always reach out to us on Instagram or via email.

Paddy Farrell

www.triagemethod.com

Hey, I'm Paddy!

I am a coach who loves to help people master their health and fitness. I am a personal trainer, strength and conditioning coach, and I have a degree in Biochemistry and Biomolecular Science. I have been coaching people for over 10 years now.

When I grew up, you couldn't find great health and fitness information, and you still can't really. So my content aims to solve that!

I enjoy training in the gym, doing martial arts and hiking in the mountains (around Europe, mainly). I am also an avid reader of history, politics and science. When I am not in the mountains, exercising or reading, you will likely find me in a museum.