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Can a juice cleanse give you a headache?


A juice cleanse involves consuming only fresh fruit and vegetable juices for a period of time, typically lasting anywhere from 3-7 days. Some people use juice cleanses as a way to detox or reset their diet. However, drastically reducing your calorie intake and cutting out whole foods can also lead to side effects like headaches.

In this article, we’ll take a closer look at how juice cleanses work, their potential benefits and risks, and what you can do to avoid headaches if you plan to try a juice cleanse.

How Do Juice Cleanses Work?

Juice cleanses involve consuming only fresh fruit and vegetable juices while eliminating all solid foods for a set period of time. Most cleanse programs provide pre-made juices that are tailored to provide nutrients and calories within a low calorie range, usually around 700-1200 calories per day.

Some popular juice cleanse programs include:

Program Cleanse Duration
BluePrint Cleanse 3 or 5 days
Pressed Juicery 1, 3, or 5 days
Juice Press 1, 3, 5, or 7 days

Most cleanse programs recommend easing into and out of the juice fast, starting with one day of all juices before and after the cleanse days.

The premise of juice cleansing is that by giving your digestive system a rest and flooding your body with nutrients, you can eliminate toxins and improve health. However, there is little scientific evidence that juice cleanses have any meaningful detoxification effect.

Potential Benefits of Juice Cleanses

While the “detox” claims are unproven, some people still report benefits from doing a short juice fast:

  • Rapid weight loss – Not all the weight is fat, but eliminating solid foods can lead to dropping several pounds quickly.
  • Kickstart a healthier diet – The restrictive nature of a juice cleanse can help break unhealthy eating habits.
  • Increased vegetable intake – Juice cleanses drastically up your fruit and vegetable consumption.
  • Improved hydration – Drinking ample fluids from juices can improve hydration.
  • Boosted energy – Some people report feeling more energized while juicing with the influx of nutrients.

However, these benefits tend to be temporary. Most people regain weight lost shortly after ending a cleanse by returning to normal eating habits.

Potential Risks of Juice Cleanses

While juice cleanses may seem like a quick fix, they carry some risks:

  • Nutrient deficiencies – Juices lack protein, fat, and fiber needed for health. Not getting enough protein can lead to muscle breakdown.
  • Low calorie intake – Consuming so few calories can slow your metabolism.
  • Blood sugar spikes – The high glycemic index of juices can rapidly spike and crash blood sugar levels.
  • Cravings and overeating – The calorie restriction can lead to cravings and overeating when you finish the cleanse.
  • Headaches – Headaches are a common side effect of dramatic changes in your diet. We’ll go into more details on juice cleanse headaches next.

For these reasons, health experts warn against following juice cleanses long-term or frequently. They are unlikely to yield lasting improvements to health or weight loss.

Why Juice Cleanses Can Cause Headaches

Headaches are one of the most commonly reported side effects of juice cleansing.

Here are some of the reasons a juice cleanse may lead to headaches:

Low Calorie Intake

Consuming very few calories can trigger headaches in some people. Extreme calorie restriction lowers blood sugar levels and may cause energy depletion that can result in head pain.

Most juice cleanse programs provide around 1,000 calories per day from juices. However, your body may require significantly more calories to properly function.

Caffeine Withdrawal

Since caffeine is not allowed on most juice cleanses, withdrawal from coffee and tea could play a role in some cleanse-induced headaches.

Caffeine withdrawal symptoms like headache tend to peak by 1-2 days after stopping caffeine intake. If your juice cleanse lasts 3 days or longer, caffeine withdrawal could be relevant.

Blood Sugar Spikes and Crashes

Fresh juices are rich in simple sugars with a high glycemic index. Their high sugar content can lead to big spikes in blood sugar when drinking juices.

Rapidly rising and falling blood sugar levels may trigger headaches in some people. Stable blood sugar is important for avoiding energy crashes that can promote headaches.


Although juice cleanses involve ample fluid intake, some people still report dehydration symptoms like headache, fatigue, dizziness, and dry mouth while juicing.

Even with juices every couple of hours, your fluid needs may exceed the fluid provided, especially if exercising. Dehydration can then exacerbate headaches.

Nutrient Deficiencies

Juice cleanses provide almost no protein, fat, fiber or many micronutrients. Deficiencies in nutrients like magnesium, B vitamins, zinc, and others could potentially contribute to headaches in some cases.

However, cleanses rarely last long enough to cause full-blown deficiencies. Still, restricting these nutrients may impact factors related to headaches like muscle function, nerve conduction, and blood flow.

Electrolyte Imbalances

Consuming only juices may impact important electrolytes like sodium, potassium, and magnesium. Electrolyte imbalances can sometimes trigger headaches in sensitive individuals.

While vegetable juices provide potassium, skipping out on sodium-containing foods can lead to imbalances that may promote headaches in some cases.

Tips to Prevent Headaches During a Juice Cleanse

If you plan to do a juice cleanse, there are some things you can do to help avoid headaches:

  • Ease into it – Start preparing your body 1-2 days before a cleanse by reducing caffeine, sugar, and processed foods.
  • Include ginger and turmeric – These anti-inflammatory juices may help prevent headaches.
  • Don’t over-exercise – Light walking is fine but avoid intensive workouts that can worsen headaches.
  • Stay hydrated – Drink extra fluids like water, herbal tea, or broth if allowed.
  • Get enough sleep – Shoot for 8+ hours per night to feel rested.
  • Manage stress – Stress can make headaches worse, so engage in relaxing activities.
  • Take breaks if needed – It’s okay to end a cleanse early if headaches become severe.

Pay attention to warning signs of low blood sugar like fatigue, dizziness, and mental fogginess. Sipping on extra fruit juices can help get quick glucose if needed.

Be sure to get medical advice if you have a history of headaches, migraines, diabetes, or low blood pressure before attempting a juice cleanse.

The Bottom Line

In summary, juice cleanses involve a dramatic calorie reduction paired with consuming only fruit and vegetable juices for up to 7 days. This extreme dietary change may lead to headaches in some people.

Potential causes include caffeine withdrawal, blood sugar fluctuations, dehydration, and nutrient deficiencies. While proponents claim cleanses detoxify and provide a nutritional boost, they are unnecessary for most healthy people.

To limit headaches and other side effects, ease into a cleanse, stay hydrated, avoid over-exercising, and don’t attempt a long cleanse if you have a history of migraines or headaches. While juice cleanses are unlikely to cause lasting harm or benefit for most people, they should be approached with caution.