Can Meal Replacement Shakes Cause Headaches? How To Prevent?

Can Meal Replacement Shakes Cause Headaches? How to Prevent?

Last Updated on July, 2024

Meal replacement shakes are all the rage because of how helpful they can be. 

Whether you want to lose weight, build muscle or have a quick meal in the middle of a busy day, meal replacement shakes have your back.

I mean- all the nutrients you would get in a regular meal but with fewer calories!? Sounds too good to be true!

However, despite all their advantages, there are concerns regarding whether meal replacement shakes can cause headaches. 

Find out whether there is any truth behind these concerns here!

Can Meal Replacement Shakes Cause Headaches?

Meal Replacement Shakes and a human feeling Headaches

Unfortunately, yes. Meal replacement shakes can cause headaches.

Meal replacement shakes can cause headaches for various reasons involving ingredients in the shakes that can trigger headaches or your body rebelling as you cut out specific elements from your diet. 

But don’t sweat it!

Keep reading to find out exactly why meal replacement shakes can cause headaches and how you can prevent this from happening.

Why Do Meal Replacement Shakes Cause Headaches?

Sugar Withdrawal

If you use meal replacement shakes to replace high carb meals, you’re likely to run the risk of withdrawal from sugar.

Studies have shown that sugar affects the reward system of the brain. 

Sugar triggers dopamine release in the nucleus accumbens, which is the same area of the brain associated with responses to addictive drugs. (1)

It also causes the release of endorphins in your brain, which are your body’s natural opioids. When your body no longer has these extra opioids, it’ll start to crave them. This craving causes symptoms of withdrawal, which include headaches.

Artificial Sweeteners

Some meal replacement shakes contain artificial sweeteners like aspartame and sucralose, and studies show that these substances can cause headaches and trigger migraines.

However, note that for artificial sweeteners like aspartame to trigger headaches, it needs to be ingested in large quantities and for a prolonged period.

So, taking around two meal replacement shakes that contain these artificial sweeteners per day for an extended period can create sensitivity towards headaches. 



When you restrict carbs (as consuming meal replacement shakes will help you do), you can become dehydrated faster. This can generally be the case when you don’t maintain a healthy balanced diet alongside your meal replacement shakes.

This is because cutting carbs leads to the release of more water as the body goes to its glycogen store to break down the carbs. This loss of water weight is, in fact, why cutting carbs helps with weight loss, BUT it does have the unfortunate effect of triggering headaches. 

Although they don’t know precisely why this is the case, experts believe that it has to do with narrowing blood vessels in the brain. But unfortunately, this narrowing of blood vessels also reduces the amount of blood and oxygen the brain gets.

Insufficient electrolytes can also play a part in dehydration headaches.


You can find certain ingredients in meal replacement shakes that can trigger headaches and migraines, especially in migraine sufferers.

Here are some of the main allergens to look out for in your shakes.

  • MSG

Monosodium Glutamate (MSG) is a flavor enhancer used in a range of processed foods, restaurant foods and drink mixes. 

MSG has been in use for roughly 100 years and it brings out the flavors of other ingredients and triggers the taste sensors in the brain.

some headache making ingredients

Although the FDA recognizes it as safe, there have been reports of people experiencing various reactions attributed to foods containing MSG.

These reactions (known as the MSG symptom complex) include headaches.

People sensitive to glutamates can also experience headaches related to MSG as a link between glutamates and trigeminal nerves has been established by a study.

  • Pea Protein

Peas are high in glutamates, and if you are sensitive to glutamates, pea protein might be what’s triggering your headaches.

If you suffer from migraines, it would also be best to avoid consuming meal replacement shakes containing the following;

  • Hydrolyzed Protein
  • Soy Protein
  • Whey Protein
  • Soy Protein

Soy protein is a common allergen, and people with this allergy display a range of symptoms that include- you guessed it- headaches.

Soy protein isolate is included in a ton of vegan meal replacement shakes, and it’s also high in glutamates like pea protein.

So make sure to check labels when you purchase your shakes.

Toxic Additions

The Food and Drug Administration does not regulate meal replacement shakes because they are classified as dietary supplements.

A 2010 study by “Consumer Reports” details that traces of arsenic were discovered in 15 commercially produced protein drinks, along with traces of heavy metals such as cadmium, lead and mercury.

Low-level heavy metal poisoning over a long period can lead to problems like muscle and joint pain, weakness and, of course, headaches.

How to Prevent Headaches Caused By Meal Replacement Shakes?

A Man Shouting Because of Headache

Gradually Reduce Carbs and Sugar

To reduce headaches while consuming meal replacement shakes or losing weight, try to gradually reduce your intake of carbs and sugar.

If you are a heavy soda drinker, completely cutting off your soda intake can also cause these headaches. So, reduce your soda consumption gradually, too, to give your body the chance to acclimate itself to less sugar and caffeine.

Increase Water Intake

To prevent headaches brought on by dehydration, increase your fluids intake. 

Your body is already a little dehydrated when you start to feel thirsty, so make sure that you drink water or tea often.

Choose Shakes With No Artificial Ingredients

As we discussed earlier, some artificial sweeteners can cause headaches, so check the ingredients in the shakes you buy to ensure that these sweeteners aren’t present.

A quick Google search should help you discover shakes that don’t contain any headache-inducing ingredients with ease.

We have a list of recommended meal replacement shakes without artificial sweeteners on our website.

Pick Alternative Approaches to Meal Replacements

If you are simply taking meal replacement shakes for convenience with no weight loss goal in mind (and if your headaches aren’t going away), you can explore the following alternatives that are equally as convenient. 

Smoothies are an excellent alternative to a meal replacement shake, and you can make them at home to ensure that they have the same nutritional value as a meal replacement shake.

For example, you can add fresh fruit and vegetables, healthy fats like avocados, proteins, etc.

smoothie meal shake

If you want something hot to take on the go, you can try pureed soups. You can make big batches that you can freeze if you don’t have the time to cook constantly.

You can also get salads to go, pre-cut veggies with hummus and healthy snacks like dried fruit, roasted chickpeas, etc. 


The thing about headaches is that they’re highly unpredictable. As Vincent Martin, MD, a UC Health physician, states, “a trigger factor does not always trigger a headache.” (2)

Various other factors that can contribute to a headache, making identifying a specific trigger difficult. But if you notice a link between a particular trigger and your headaches that exist 50 percent of the time, then that is most likely to be your headache trigger.

If this is the case for you with meal replacement shakes, be conscious of the ingredients in the shakes you buy. 

In addition to this, ensure to maintain a balanced diet alongside your meal replacement shakes.

And finally, if you are still unable to get rid of your headaches, you can try out some of the equally convenient alternatives detailed above.


Meal replacement shakes help with weight loss, proven by a study showing a 7.8% body weight loss for those using shakes vs 1.5% for the control group. This is due to high protein content, which promotes fullness without added calories.

Common side effects of meal replacement shakes include digestive issues, headaches, and potential health problems from artificial ingredients like sucralose and maltodextrin. To minimize these, have a balanced diet and check shake ingredients.



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Jennifer Pantall
Jennifer Pantall is a Nutrition Therapy Practitioner. She loves tennis and has one daughter with a lovely husband whom she adores. Jennifer also loves to spend time outdoors playing with her dog or walking in nature. You can find more about me here.

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