Why You Get Muscle Cramps or Body Aches While Fasting (and How to Cope)

Eating restrictions can sometimes put a strain on your body, which is why you may experience muscle pains or body aches during fasting.

A lack of water and certain nutrients may be behind your discomfort. Other factors, like your exercise routine, can also contribute to cramping while fasting.

Here’s a breakdown of the possible causes of muscle cramps during fasting and how to treat or prevent them.

What Are Muscle Cramps?

• Dehydration
• Electrolyte imbalances
• Muscle fatigue
• Loss of muscle control

“Research does suggest inadequate stretching and muscle fatigue lead to uncontrolled contractions in the muscle,” says Sharon Zarabi, RD, program director at Northwell Health’s Katz Institute for Women’s Health in Long Island, New York.

In addition, if you overexert yourself, don’t exercise regularly, or skip a stretching routine, your muscles will most likely become fatigued, and their neural reflex activity (the movement your body makes without thinking) will be affected, Zarabi says.

Can You Get Muscle Cramps While Fasting?

“Fasting or very low-calorie diets can cause cramping because you are depleting the muscle of minerals and electrolytes,” Zarabi says.

Luckily, there are ways to address these body aches during fasting. ”Cramps can be relieved through gently stretching and massaging the muscle,” Zarabi says. “Hold a stretched position until the cramp stops. Apply heat to tense or tight muscles, or cold to sore, tender muscles.”

To reduce the risk of cramps or aches, ”always warm up and cool down before and after any physical activity,” Zarabi says. ”Ensure you are hydrated before and after workouts. Remember, your body is composed of 80 percent water. It is essential and you need to drink it!”

• Stretch the affected area.
• Massage the affected area with your hands or a massage roller.
• Stand up and walk around.
• Apply heat or ice.
• Take over-the-counter pain relievers, like ibuprofen or acetaminophen.

Preventing Cramps While Fasting

• Increasing hydration
• Getting more rest
• Stretching your muscles

Body weight (in pounds) ÷ 2 = minimum ounces of water to drink per day

Getting enough electrolytes is also key to avoiding cramps. Magnesium is one major electrolyte that helps calm the muscles and is crucial for muscle contractions in neuromuscular signaling, which is directly associated with muscle cramping, Zarabi says.

• Spinach
• Legumes, like beans and lentils
• Nuts, like almonds and cashews
• Seeds, like pumpkin and chia seeds
• Whole grains, like brown rice and whole-wheat bread

”Review your diet with a registered dietitian-nutritionist to assess adequate protein, healthy fats, complex carbs, minerals, and hydration,” Zarabi says. “Food is medicine and our best form of treatment, so no need to run to the pharmacy for supplements. Reevaluate your diet and ensure you have all colors of the rainbow on your plate.”

If you’re restricting your eating, make sure you’re still getting enough water and electrolytes, like magnesium, potassium, and calcium, from food to keep cramps at bay.

If fasting body aches persist, consider seeing a doctor to rule out any circulatory and neurological issues, Zarabi says. She also says that the pain could be a side effect of medications you’re taking, and your doctor can help you determine whether this is the case.

The Takeaway

• Muscle cramps, or spasms, can occur for various reasons, including dehydration, working out in the heat, muscle fatigue, or an electrolyte imbalance.
• Fasting can result in cramping if you’re not getting enough key nutrients through food.
• If you are dieting or fasting, make sure to stay hydrated and eat foods rich in magnesium, a key electrolyte for good muscle health.