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What Happens If Your Macros Are Too Low

What Happens If Your Macros Are Too Low (7 Issues)

‘Macros’ refers to macronutrients, which are nutrients that the body needs in large amounts. The primary macronutrients are protein, fat, and carbohydrates. 

When tracking macros people monitor their macros, often while reducing their overall calorie intake. This approach of tracking macros has become an increasingly popular way of losing weight, specifically fat. 

However, if you don’t hit your macros targets and don’t consume enough calories you can end up with some serious issues.

Below I’ve explained why it’s important to hit your macros targets, as well as what happens if your macros are too low.

How Important Is It to Hit Your Macros

It’s really important to hit your macros. If you don’t hit your macros then you won’t see long-term results from this diet. You can also experience a range of negative health impacts, especially if your macros are too low.

As with any diet or lifestyle change, consistency is key. So when tracking macros it’s important to hit your macros target each day. 

If your macro split is 40/40/20 for protein, carbs, and fat then you should be sticking to this as much as possible if you want to see results from tracking macros.

But hitting your macros isn’t just important in order to see results, it’s also important because you can develop health problems when your macros are too low.

Do You Have to Hit Your Macros Exactly?

Tracking your macros is important, but it doesn’t need to be exact. So long as you don’t go significantly over or under your macros target each day then you should still see results in the long term.

Whilst hitting your macros is important, it doesn’t have to be 100% exact. This doesn’t mean that you should go well above or below your macros target. It just means that there is some flexibility when hitting macros.

Related – Hitting calories but not macros

If you’re hitting your macros target most of the time, then going slightly over or under occasionally shouldn’t make a big difference and you should still see results in the long term.

However, if you consistently don’t hit your macros, or if you are going well under or above your macros target then you aren’t going to see results.

What Happens if Your Macros Are Too Low

There are a number of things that will happen if your macros are too low. The main ones include:

  1. You lose muscle instead of fat
  2. Your metabolism slows
  3. You feel sluggish and fatigued
  4. You feel hungry all the time
  5. You’re constipated
  6. You experience hormonal imbalance 
  7. You have trouble sleeping

When your macros are too low you can experience a range of different problems.

1. You Lose Muscle Instead of Fat

People often track macros in order to lose fat and gain muscle. However, if your macros are too low then the opposite can happen and you can experience muscle loss.

Your body will start to burn muscle instead of fat if you’re not consuming enough calories. 

Your body needs a certain amount of calories each day just to sustain yourself. If you’re following a macro diet then you would reduce the number of calories you’re consuming in order to lose weight.

However, if you cut your calories too much or too rapidly and go below the amount needed each day just to sustain yourself then your body goes for its carb stores for energy. 

If those carbs aren’t available because you aren’t consuming them then the body starts to burn glycogen, which is a form of glucose stored in your muscles. At this point, you’d start to experience muscle loss.

Your body can also start to lose muscle instead of fat if your protein intake is too low. Protein is crucial for muscle growth and development. 

If you aren’t getting enough protein in your diet then your body can’t build more muscle and as you lose weight you’ll lose muscle instead of fat.

Overall then, if you want to avoid losing muscle and burn fat instead then you need to be consuming enough calories each day. These calories also need to come from your key macros, with a focus on hitting your protein target. 

2. Your Metabolism Slows

When trying to lose weight, or lose fat, people often think that they need to radically reduce the number of calories that they consume. 

But as I explained, your body needs a certain amount of calories every day just to sustain itself. 

So if you cut your calories too much or too rapidly and go below the amount needed each day just to sustain yourself then you can do long-term damage.

This is because when you aren’t consuming enough calories your body goes into survival mode and starts trying to preserve itself by slowing down your metabolism. Essentially, your body won’t be burning as many calories anymore.

When your metabolism slows down it’s harder to achieve weight loss results in the long term. 

Also, when you stop cutting calories and eat a higher amount of calories again it’s much easier to gain weight and even harder to lose it.

So, you need to be reaching your macros targets and be eating a sufficient amount of calories each day in order to see results, especially in the long term.

If you feel like your metabolism has slowed then the good news is that there are different things you can do to speed it up again, including moving your body more and getting a balanced diet.

3. You Feel Sluggish and Fatigued

If your carbohydrate intake is too low then you’ll find yourself feeling sluggish and fatigued.

Carbohydrates are an essential micronutrient and they’re crucial to your overall health in a number of ways. One important thing about carbs is that they’re an essential source of energy and you need them to sustain energy levels throughout the day.

This is because of blood sugar levels. When you eat food containing carbs, your digestive system breaks them down into sugar, which enters your bloodstream

As blood sugar levels rise, insulin is produced which triggers cells to absorb blood sugar for energy.

If you don’t consume enough carbs then this can lead to tiredness and fatigue as your body struggles to maintain its energy levels.

With this being said though, not all carbs are equal. Refined carbs such as white pasta and white bread provide a short burst of energy as they cause a spike in blood sugar levels. 

Although this might feel great at first as your blood sugar levels come down again you’ll find yourself feeling worse off.

So it’s important to focus on complex carbs, such as whole grains, brown rice, and quinoa. These complex carbs are more nutritious and contain more fiber. As higher fiber foods are harder to digest they leave you feeling fuller for longer.

Also, as complex carbs don’t cause a sudden spike in blood sugar levels they help to provide a more gradual and steady level of energy.

The bottom line then is it’s important to make sure your carbohydrate intake is at the right level when following a macro diet. 

When consuming carbs you should focus on complex carbs that are going to help you feel full for longer and provide a slow release of energy throughout the day.

4. You Feel Hungry All the Time

If your macros are too low then you’ll find yourself feeling hungry all of the time. This can be caused by different things.

As I explain in the last section, carbohydrates, particularly complex carbs, are crucial for maintaining steady blood sugar levels. If your blood sugar levels aren’t stable then you can experience intense cravings.

This is because when your blood sugar levels drop your body craves something that will spike them again. So you might find yourself craving foods that are high in sugar.

See also – How to reduce hunger while cutting

Feeling hungry all of the time can also be a sign that you’re not consuming enough protein. Protein is great for keeping you feeling full and stopping hunger/ cravings.

However, as with carbs, not all forms of protein are the same. When thinking about feeling full for longer you should focus on good protein sources like eggs, meat, meat-alternatives, and vegetables. Each of these foods has been shown to keep you fuller for longer.

Feeling hungry all of the time can also have a psychological cause. If you aren’t hitting your macro targets then you probably aren’t eating enough. 

When you deprive yourself of food or specific foods then it becomes all you can think about. This is something many people experience when following restrictive diets.

The great thing about counting macros is that so long as you account for the foods you’re eating, no foods are off-limits. So if you’re hitting your macro targets then you shouldn’t be feeling hungry all of the time.

5. You Become Constipated

If your macros are too low then you can experience digestion problems, including constipation. 

As I mentioned already when you aren’t consuming enough calories your body essentially goes into survival mode and your metabolism slows. This process also affects your digestive system, which can slow down in order to preserve calories and energy.

As a result, you can experience digestive problems.

Although all types of macronutrients (protein, carbs, and fats) are important for proper digestion, digestive problems when your macros are too low are usually caused by not eating enough carbs, particularly high fiber carbs. 

Fiber is important for helping to ensure proper digestion. Whole grains, brown bread, and quinoa are particularly high in fiber which will help your body digest foods and keep your digestive system working as it should.

Other foods that are high in fiber include beans, fruits like apples, potatoes, and cereals.

So if you want to keep your digestive system working as it should you need to ensure you’re continually hitting your macros target.

6. You Experience Hormonal Imbalance

If your fat intake is too low then you can experience hormonal imbalance. Fats are necessary for hormone production as well as maintaining the function of your hormones. 

Fats have a bad reputation. When it comes to dieting most people are trying to lose fat, so they think that they need to eliminate all sources of fat from their diet. 

However, not all fats are the same. 

Artificial trans fats for example have been shown to increase your risk of heart disease, as well as potentially increase your risk of diabetes. As these kinds of fats are more likely to promote bad health, they shouldn’t be making up a big part of your macros.

However, other types of fat have an essential role in maintaining good health, including ensuring hormonal balance. They do this through rebuilding cells and stabilizing hormones.

So foods containing good fats, such as nuts, olive oil, salmon, and other fatty fish, which are high in omega-3 and good fats, should be a key part of your diet.

Overall then if you don’t want to experience hormonal imbalance then make sure you’re hitting your macros targets, particularly the target for fats in your diet.

7. You Have Trouble Sleeping

As well as making you feel tired and fatigued, having low macros can also cause sleep problems.

There’s plenty of evidence that shows a nutritious diet is essential for sleep. This means having a well-balanced diet and consuming enough calories each day to ensure that your body is getting the necessary nutrients.

If you aren’t eating enough, and aren’t maintaining a healthy diet, then this will adversely affect your sleep. This might involve difficulty falling asleep or trouble staying asleep.

Given how important sleep is to our overall health, it’s important to ensure you’re supporting your sleeping pattern by hitting your macros and consuming enough calories.

In Summary

When dieting, getting your calorie intake in order should be a priority. The calorie intake should also be set based on your personal goal. If you want to lose body fat, you’ll need to have a caloric deficit. 

The danger when just focusing on calories though is that you’ll neglect the macros. There are a number of issues that can arise if your macros are too low and these will impact mood, performance in the gym, ability to stick to a diet, and ultimately the end result. 

Therefore, when dieting, make sure you set a reasonable calorie target but that you also get your macro ratio to reflect this figure. 

A diet containing just protein as your calorie source will definitely help you lose weight but the absence of carbs and fat could cause significantly greater issues. This is an exaggeration but the impact is still a concern!

Macros being too low is definitely an issue but I’d also recommend checking out this further reading: 

What happens if you go over your macros

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