Bread Makes Me Tired & Fatigued: 3 Reasons + How To Fix

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If you feel tired, fatigued, or sluggish after eating a sandwich, you are not alone. There are several reasons why you are feeling this way after eating bread. 

As a Registered Dietitian, I always like my clients to understand the relationship between their food and any body reaction.

So, why is bread making you tired?  Bread can make you feel tired because you might have a slight gluten intolerance. Also, white bread is high on the glycemic index, which means a high glucose response leading to a sugar crash. Finally, if you consume bread with high tryptophan foods (i.e. cheese), it can increase serotonin, making you feel tired.

Not only will this article help you determine why bread is making you feel this way, but there are several solutions you can implement to avoid getting tired after eating bread.

3 Reasons Why Bread Makes You Tired, Fatigued And Sluggish

3 reasons why bread makes you tired, fatigued and sluggish

1. Gluten Intolerance

Guten is a protein found in wheat, barley, and rye. Some people have difficulty digesting gluten (celiac disease). According to the Celiac Disease Foundation, they estimate that 1 in 100 people suffer from this condition, with the majority of them undiagnosed. 

When someone with celiac disease eats food that contains gluten, their body senses it like a strange object in the body, leading to an autoimmune response. This means that the body is attacking the small intestine to get rid of this unknown molecule. 

When this happens, it leads to symptoms such as bloating, diarrhea, gas, nausea, vomiting, pain in the abdomen, and even feeling tired. 

If you doubt whether or not you have celiac disease, you can eliminate all gluten foods for four weeks. If your symptoms get better, then you have some gluten intolerance. 

For a more detailed diagnosis, you should visit a healthcare provider who can run tests on you to determine if you are celiac. If you decide to go to the doctor, continue your usual diet. If you eliminate gluten on your own and then go to the doctor, it could give you a false negative result. 

However, from my professional opinion, if you’re only getting tired after eating bread, and not experiencing any of the other symptoms that are common with a gluten intolerance (bloating, nausea, etc.), then the cause of your fatigue may be due to something else.  

2. Blood Glucose Swings

Another reason bread is probably making you tired can be related to your blood glucose response.

The way food affects our glucose response is measured by the glycemic index. The glycemic index is a scale that goes from 0 to 100 on how quickly a food can raise your sugar levels. It is divided into three categories:

  • Low glycemic index: 0 to 55
  • Medium glycemic index: 56 to 69
  • High glycemic index: higher than 70

The higher the number on the scale, the higher the sugar response will be since it is digested and absorbed faster by the body. 

The type of bread you choose (white vs. whole grain) can have a different glycemic index. White bread is generally higher on the glycemic scale (around 71) since it is easy to digest. This creates a high sugar response in the body.

While eating high glycemic foods before a workout is good, if your body doesn’t need this high-energy spike, it will work to stabilize your sugar levels again, making them drop. This sudden drop in your sugar levels can cause you to feel fatigued, tired, and sluggish. 

A study on 82 overweight adults found that people who included food high in the glycemic index scored 26% higher in showing fatigue symptoms than those who chose lower glycemic index foods. 

3. The Culprits Are The Toppings 

Finally, the reason you are feeling fatigued or tired might be nothing to do with bread but with the foods you are having along with bread. 

Proteins are made up of amino acids.  One amino acid is called tryptophan. Tryptophan is a common amino acid found in high protein foods like eggs, cheese, and turkey. It is used to create melatonin (which regulates the sleep and wake cycle) and serotonin (the happy hormone). The combination of these hormones together can make you feel tired. 

One more thing to note about bread and tryptophan:  

Eating bread will increase your insulin response, which in turn increases the absorption of tryptophan in the brain, increasing the effect of fatigue in your body. 

Therefore, if you are eating a high protein diet with bread, this means that the reason you are feeling tired, fatigued, and sluggish might be due to the high tryptophan foods that you are adding. 

Glycemic Index In Bread Compared With Other Foods

The glycemic index determines how high the sugar response is going to be in the body. 

The higher the sugar response, the higher the sugar crash, making you feel more tired, fatigued, and sluggish. 

In the following table, I compare several foods related to bread and their glycemic index

FoodGlycemic Index
Cornflakes93 (High)
White Rice89 (High)
White Bread71 (High)
Spaghetti58 (Medium)
Oatmeal55 (Medium)
Quinoa53 (Medium)
Corn Tortilla52 (medium)
Whole Grain Bread51 (Medium)
Brown rice50 (Medium)
Black Beans30 (Low)

Keep in mind that only carbohydrates are in the glycemic index since they are going to create an insulin and sugar response. Fats and proteins are not shown since they won’t create a sugar response. 

As you can see, white bread is in the high glycemic index category, and whole wheat bread is in the medium glycemic index. 

The reason for the difference is because of fiber.  

Fiber is a type of carb that stays longer in your stomach. This allows the carbs you eat to be released slower than those with no fiber. 

That is why white bread has a higher glycemic index, since it has less (or even no fiber) than whole wheat bread. 

5 Ways To Avoid Getting Tired From Bread

5 ways to avoid getting tired from bread

1. Switch To a Gluten-Free Bread

If you think you cannot process gluten, the best thing you can do is switch to gluten-free bread. They are often made with gluten-free foods like potatoes, almond flour, lentil flour, coconut flour, or chickpea flour. 

Eliminating gluten in your diet can reduce feeling tired throughout the day. The good thing is that there are now several brands that offer gluten-free bread like Young Kobras Organic and BFree Gluten Free Pita Bread.

Also, you can make baked goods at home that are gluten-free. You only need to use items like almond flour or coconut flour. 

One of my favorite recipes for those that are missing baked goods like donuts is a High Protein Cauliflower Donut (Keto & Low Carb Friendly).

2. Decrease Your Bread Intake

Another thing you can do is decrease your bread intake throughout the day. Everyone has a different tolerance when it comes to symptoms. 

You can start with having only one slice of bread and see if you feel tired, fatigued, or sluggish. 

If you don’t have any symptoms, you can increase another slice, and so on until you determine your tolerance. 

3. Go Whole Grain

The glycemic index has a significant impact on whether or not you are likely to feel tired. Higher glycemic response means that your sugar levels are likely to crash the same way they rise. 

If you want to decrease this symptom, replace your white bread with whole-grain bread. This will make you go from having a high glycemic index food to a medium one. This means that the sugar response will be softer with the latter one. 

If you have a loaf of bread in mind, check how many grams of fiber it has. Make sure that it has at least 3 grams of fiber to ensure that it won’t spike your sugar levels as much. 

If you are looking for whole-grain bread recommendations, you can check my other article 8 Best Bread For Bodybuilding (Bulking & Cutting)

4. Learn How to Decrease The Glycemic Response

Proteins, fats, and fiber takes longer to digest in the body, which means you have a lower sugar release whenever you combine a high-carb food with one of these. 

Thus, if you are trying to decrease your sugar response, you can combine bread with either a protein (chicken, salmon, or meat), a healthy fat (avocado, olive oil, nuts, or seeds), or a high fiber food (non-starchy veggies). 

By reducing your sugar response, you are less likely to have a sugar crash right after eating bread, avoiding the feeling of tiredness. 

5. Avoid High Tryptophan Foods With Bread

If bread is not the culprit and the reason are the foods you add along with it, you want to avoid having high tryptophan foods. 

Avoid adding foods like pumpkin seeds, cheese, eggs, tuna, salmon, and chicken breast to avoid feeling fatigued. 

Other Foods That Can Make You Tired


About The Author

Brenda Peralta

Brenda Peralta is a Registered Dietitian and certified sports nutritionist.  In addition to being an author for FeastGood.com, she fact checks the hundreds of articles published across the website to ensure accuracy and consistency of information.