Why You Need to Make Adjustments to Your Macros as You Diet

Online macro calculators don’t work – they just provide a starting point from which to work from.

So you’ve gone to an online macro calculator, plugged your all your relevant information, out pops a couple of sets of macros for your rest and training days and you proceed happily on your diet. Then, some weeks later you stop seeing any changes and appear to have stalled. Why could this be the case?

Well, there are multiple reasons. Now, before we get into them I don’t want to come across as critical of the people who have spent great time and effort to create these calculators to help people. They are good tools to get people going but they are not going to get you all the way. The problem comes when people start thinking that such calculators can predict a diet’s progress accurately. – It says you should be losing 1lb of fat per week because you have calculated a perfect x000 kCal deficit, and so when that doesn’t happen people start to freak out. – How can it be? Did I not calculate accurately?

This is what we will get into in this article.

Assumptions we’re making:

  • You have stalled and need to make a change. So that you know how to identify this situation you need to have read the two posts on tracking, “How to Track your Progress When Dieting,” and “Patience, a Key Tool for Diet Success.” Please.
  • There is no muscle growth happening while being in a deficit. – Lean body mass remains constant. (Yes, growth while in a deficit can happen in a deficit under certain circumstances but that’s out of the scope of this article.)

1. You might not be in a calorie deficit

This change is due to water weight and it happens for a couple of reasons.

Firstly, because overall carb intake for the week usually goes down due to the lower carb intake on rest days. As carbs suck in 3-4x their weight in water it’s easy to see how big this can be. (and also why you get the scale weight discrepancy between your training and rest days.)

Secondly, and this is less obvious, is the decreased salt intake that occurs when many people decide to go into “cutting mode” and they naturally tend to eat “cleaner foods”. (JCDeen has a great video which sums up why I think the clean eating thing is a bit of a misnomer but doesn’t change the fact that people have a tendency to eat less salty, perceived healthier foods when they start their diets.) This causes an initial drop, which rights itself to previous levels in about a week (see FAQ).

I’d say that putting these two factors together you pretty much have the biggest reason that many non-experienced dieters have for failing in the initial stages of their diet. Either the inflated expectations that these weight changes bring the lead to subsequent disappointment with progress or the fear of dropping weight too quick leads people to prematurely change their calorie intake upwards, removing what was a functional calorie deficit.

2. Our energy needs change as we diet

The Lighter We Get the Fewer Calories We Burn

There are three reasons for this: The energy required to be you is less, so your base metabolic rate (BMR) drops. You’re eating less food, so the calories required to consume that food (TEF) are fewer. And because you are lighter your exercise program (TEE) burns fewer calories.

BMR – Base Metabolic Rate drops
TEF – Thermic Effect of Food drops
TEE – Thermic Effect of Exercise drops

Because of these changes, a single calculation made initially will not continue to work in the vast majority of cases.

NEAT Variance

This is your spontaneous physical activity, known as NEAT in geek-speak (Non-Exercise Activity Thermogenesis). We all feel more lethargic on diets right? Fidgeting, moving around, propensity to take stairs vs elevator etc., decreases.

The problem with NEAT (and why I have given it a separate sub-heading) is that there are vast individual variances. Some people seem to respond minimally in this regard, some a great deal. (In one study, when subjects were put on a diet 1000kCal above calculated maintenance, the range of increase in NEAT was from -98 to +692 kcal/day.) It’s not unreasonable to assume that people are affected differently when considering the opposite: a deficit.

No calculation can take into account these individual NEAT differences.

Metabolic Adaptation

This is the adaptive component of your BMR that is not predicted by weight loss. Basically, it is caused by hormonal changes that happen when your body senses a calorie deficit, and so starts doing what it can to decrease your daily energy needs to stop you starving to death in certain survival situations. Modern dieting clearly isn’t a survival situation, but unfortunately, our bodies can’t tell the difference between prolonged calorie restriction and starvation, so it’s something we have to deal with.

This adaptive component is very real, but smaller than many people think. The largest decrease in BMR due to this adaptive component observed was in that Minnesota Semi-Starvation study and was measured to be about 15%, once the change in total daily energy expenditure, (TDEE) due to weight loss was taken into account.

3. Suboptimal macro ratio setting

Referring here to the three macronutrients: protein, carbohydrate, and fats.

Fatter folks tend to do better on more fats relative to carbs; leaner folks can get away with more carbs. On top of this, some folks simply seem to do better with relatively more of one than the other. This is exactly why I’m not a fan of online calculators and prefer people to put a little thought into their macros. Which is why I wrote my own guide on how to calculate them.

Now I should be clear, a suboptimal macro setting can in the long-term is not going to affect a person’s fat loss efforts (assuming adequate protein intake and a resistance training program). It will still be a calorie deficit after all. However, I have definitely seen fewer stalls, less hunger, and improvements in mood and performance when details are catered to the individual. These side-effects affect long-term compliance and ultimately then, results. I’ll touch more on this in the next post but it’s often a case of ‘try it and see.’


While we can predict somewhat the decreases in energy needs (TDEE) that happen as we get smaller, we can’t predict spontaneous physical activity (NEAT) changes, or metabolic slow-down (without getting thermometers out).

So the only practical way to proceed with your diet is to adjust things relative to your current intake – a fresh macro calculation is unlikely to work.

Are all macro calculations initially a guess then? Well yes, to an extent I would say so, but we all need a place to start. From there it’s essential to make adjustments based on your tracking data as you progress.

So how should one adjust as they go? That’s for the next post, “How to Manipulate your Macros”

Metabolic Damage: Cause for Concern?

In short, no.

People are quick to latch onto something to explain their lack of progress. This happens in all areas but especially dieting, where people can become neurotic. – Look at the boom in the supposed food intolerances that we have had in the last 20 years (just check out how many more special meals are being passed around the aircraft next time you are on a long-haul flight). Assuming the worst for ourselves, as we all like to think of ourselves as unique and special, is why I think the idea of Metabolic Damage as a concept has received a lot of attention. Exaggerate a problem, call it a scary name and people will flock to it. And while I have no doubt there are many well-meaning bloggers out there wanting to warn people of the pitfalls (post-diet rebounds, etc.) of setting their calorie intake too low for too long, there is an equal number trying to take advantage of people’s fears.

So what is the truth behind Metabolic Damage? – It’s just your body’s adaptation to dieting.

The popularity of the concept comes in part from people thinking that a single calculation at the start of a diet can predict progress through to the desired result. Then when it doesn’t, they post on a forum with their macro numbers, and voracious fitness reader number 1 does a calculation and concludes that the person has metabolic damage (because that’s what they just read about), to then be backed up by well-meaning forum bunnies 2-9.

As you now know, they are likely underestimating, or not taking into account:

  • Changes in TDEE due to weight loss
  • NEAT variance
  • Individual macro setting

Remember that starvation study? There was a 40% drop in the TDEE of those poor, emaciated fellas by the end of it, just 15% due to metabolic slowdown.

Now, add to this the tendency for 1. Under-reporting of calorie intake, 2. Binges that tend to be forgotten (more under-reporting) and 3. Water-weight games (retention and sudden whooshes – especially common in women, and during periods of high stress), and it’s easy to see how this issue has been blown up. Especially as there will be people with legitimate hormonal issues (that they don’t know about) jumping in and fueling the fire.

Now, I was going to write an entire post on the subject of metabolic adaptation but Lyle McDonald completely nailed it in an issue of the AARR which has just been published online for free, ‘Another look at metabolic damage‘. If you’ve still got questions then ask away there. – Lyle knows way more than I.

Practical tips on adjusting macros after long periods of dieting or low-carbing in the next post.


Thanks for reading.

Browse the other diet adjustment guides using the menu at the top, or get access to my full book on the topic of how I adjust the diets of my clients to take them to shreds and how you can do that too, here.

Questions welcomed in the comments as always. – Andy. 

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About the Author

Andy Morgan

Hi, I'm Andy, co-author of the highly-acclaimed 'Muscle and Strength Pyramid' books and founder of RippedBody.com. This site is my sincere effort to build the best nutrition and training guides on the internet. Some readers hire me to coach them, which I've been doing full-time, online, for the last seven years. If you're interested in individualized, one-on-one coaching to help you crush your physique goals, let's start the conversation. (You can read more about Andy here.)


  1. […] Metabolism is adaptive. Calorie needs increase over time when bulking, and decrease over time when cutting. […]

  2. […] [*Also known as a protein sparing modified fast – ~500kCal intake mainly from protein + leafy veg and a few essential fats. It’s an emergency case only diet (athletes that have left it too late to make their weight class for example), which Lyle is very clear about with his warnings at the start of the book. It wasn’t necessary for Shane to have done this and put him at a big risk of rebound/quick fat gain when coming off it due to severe metabolic adaptations.] […]

  3. […] to reduce the energy that you’d require to function – a survival mechanism known as metabolic adaptation. This is normal, not something to worry about, but best to be aware of. As you increase your […]

  4. […] and you’ll need to adjust your macros as you progress with your diet anyway (reason covered here), so even if you over, or underestimate slightly it’s not a big deal. Furthermore, if […]

  5. Mahendra says:


    This article was really informative and your website has been absolutely amazing.

    It’s helped me so much and I’ve been making some really good progress on my fat loss journey because of it.

    Thank you.



    1. Kameron says:

      Ok so if this has been addressed in 129 comments below, I apologize in advance. This article states: “So the only practical way to proceed with your diet is to adjust things relative to your current intake – a fresh macro calculation is unlikely to work.” Would you kindly provide an example as I’m not sure I completely understand.

      I re-read the article several times and also the next article :“How to Manipulate your Macros”, but still am unclear as to why a macro recalc is not recommended esp since fat loss is not linear and as the article states, the The Lighter We Get the Fewer Calories We Burn. Based on that solely, it seems a macro adjustment would be warranted. I guess what I’m asking is what exactly are the “things” that need adjusting.

      I ask because in 2.5 months I have lost 3.2% (14 total lbs) and do NOT want to lose anymore weight only bf and suspect I need to make adjustments somewhere.

      Thanks for your diligence in attending to alllllll of the questions (most repeated I’m sure) that get tossed your way. If one of your goals in life is to make a difference, I am quite certain you have succeeded, so thank you.

      1. Andy Morgan says:

        Hi Kameron. Questions help me to see where my explanations weren’t sufficient, or were confusing, so no need to apoloigize and thank you for asking.

        A macro adjustment will be needed, I just don’t recommend that you do it by re-calculating your needs based on your new weight and body fat percentage using the regular TDEE formulas because your metabolism will have adapted. The best way to proceed is to adjust reduce relative to your current intake.

        You know from the other article, “How To Manipulate Your Macros” that it takes approximately a 500kcal deficit to lose 1lb of fat per day. So, if you’ve been trying to lose 1lb per week and have only been losing 0.5lbs on average, you’ll need to reduce caloric intake by 250kcal each day to stay on target.

        When looking to halt weight loss, initially you just do the opposite. You’ll then need to keep adding over a few weeks in increments to find your regular maintenance calorie intake. The guide for that is here:
        How Do I Find Maintenance Calorie Intake After Dieting?

        I’ve put together a free email course that will take you through all of this stuff in stages which you may find useful. The Diet Adjustment Mastery Mini Course.

    2. Andy Morgan says:

      Most welcome Mahendra. I appreciate you taking the time to comment and let me know.

  6. Josh Wolff says:

    Mr. Morgan,

    I have been trying to do my due diligence before asking this question, but I cannot find a reference in the material provided.

    Why do you choose not to train people who do not eat meat?

    I am not asking to be critical, I am merely curious if you feel a vegan or vegetarian diet would be a limiting factor and why.

    1. Melinda Royce says:

      Oh dear the vegan ‘pain in the arse’ comment, has me rolling in laughter!

    2. Andy Morgan says:

      Hi Josh, thanks for the question. Please call me Andy, Mr. Morgan is my dad.

      Why do you choose not to train people who do not eat meat?
      First and foremost, it’s because these people tend to be a pain in the arse personality wise. As a second but still important consideration, it’s because the way I work (letting clients choose their own foods within a rule framework for meeting macro requirements, not monitoring specific foods) could be insufficient when it comes to ensuring that certain types of vegetarian diet aren’t deficient in their protein requirements (in terms of protein completeness). Such things should be handled by a Registered Dietician.

      I am merely curious if you feel a vegan or vegetarian diet would be a limiting factor and why.
      If protein requirements are met with a varied diet, then it (protein completeness) won’t be an issue and the diet shouldn’t be a limiting factor. That’s not going to be possible with a vegan diet to my knowledge (which admittedly is limited as I lack interest due to not having any skin in the game so to speak).

  7. ibraden18 says:

    Hi Andy. I know you recommend slowing the rate of fat loss as clients get leaner–but are there specific How To’s for this process? That is, if a client is about to cross the threshold into single digit BF% and has been losing 1-1.5 lbs per week at X calories, would you suggest bumping calories to X + 200 or something of the like in order to slow weight loss down a bit?

    Thank you sir,

    1. Andy Morgan says:

      Hi Ian, yes that’s right.

  8. Andre says:

    Hello Andy,

    I just read your E-Book ‘The Last Shred’ and was curious why you do not use any ‘ReFeed’ Days on your diets as described in the Eric Helms nutrition book.



    1. Andy Morgan says:

      Hi Andre, thanks for the question.
      Refeeds are part of the overall diet set up. The adjustments strategy is independent of that.

  9. Jon says:

    Hi Andy,

    I would like to get your thoughts on the following idea:

    Is it possible to be too low on a calorie-deficit (from lack of eating and not purposefully through dieting) and then embark on a cutting program (training/calorie deficit) where the calculated calorie deficit is higher than the intake the body was used to having before training?

    I’m thinking this is may be my situation but I’m not entirely sure since I don’t keep track of calories/macros when I’ve fallen “off the wagon”. However, I feels as if I used to eat much less calories during those break times than when I started training. Mainly due to not making meals a priority. Several times I have started a program, gained weight despite crossing all my T’s and dotting the I’s – then stopped

    I’ve wondered if the sudden increase in calories on a new program, even though I’m in a deficit, could be causing that weight gain or no movement at all?

    I don’t really see anyone talking about this so wondered if you had a take on the matter. Thanks, Jon

    1. Andy Morgan says:

      First and foremost, you need to start tracking your intake, cause unless you do you’ll be forever stuck second guessing yourself.

      Here’s what generally happens:
      1. Someone could have been dieting without counting (thus lowering their metabolism a little). In the majority of cases people successfully diet (for a time) without counting by lowering carb intake, which lowers their water and muscle glycogen balance in the body considerably. This is often confused with fat loss.
      2. Weight loss stalls and they decide to start counting, which inevitably involves a calorie intake calculation.
      3. The calorie calculation will not take into account for the slightly lower metabolism, so it will be slightly too high.
      4. Furthermore, calorie requirements may be set a little higher than they should if they used a calculation technique such as the Katch-McArdle formula, because people underestimate how much body fat they carry.
      5. If people calculate their macros also, they’ll be reintroducing carbs into their diets, which will bring about an increase in water balance and glycogen balance. People confuse this with fat gain.

      The sum of it is that people often set their calorie intake a little high (minor issue which can be corrected after tracking for a few weeks with an adjustment), but they get confused/panic when they gain weight initially, not realizing that it’s water. They quit, thinking they have screwed up, or they simply don’t have the patience to wait for a few weeks till they have established a baseline from which to adjust.


  10. Holden says:


    Quick question for you…so I’m on day 5 of Week 1, and I set up my macros and everything according to your guide. The only thing that I didn’t do was this:

    “There is a school of thought that it can be beneficial for nutrient partitioning (and therefore body composition changes) to have more calories on the days you work out, and less on the days you don’t. Martin took this a step further by experimenting with higher carb/lower fat intake training days, and higher fat/lower carb intake rest days, while combining it with morning fasts.”

    So far I’ve been eating the same exact overall amount of calories and macros for each day, so my question is at what point should I make the transition to that^^? Is it important enough that I should even be worrying about it?

    1. Andy Morgan says:

      Hi Holden. Any point you feel comfortable doing it. If you’re entirely new to this then I’d leave things as you are for now while you get used to it all.

Questions welcomed. (Over 16,000 answered)

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