Dry Fasting for Weight Loss: US Dietitian Explains What Happens During a 36-Hour Fast

May 25, 2025

In recent years, dry fasting—a practice where individuals abstain from both food and water—has gained popularity among those seeking rapid weight loss. While intermittent fasting and water fasting have long been discussed in the health and fitness community, dry fasting is now drawing attention for its purported benefits. But what really happens to the body during an extended dry fast?

What is Dry Fasting?

Dry fasting is a more restrictive form of fasting that prohibits both food and liquid intake for a set period, often ranging from 12 to 36 hours. Proponents claim it accelerates fat loss, detoxifies the body, and may even improve metabolic health. However, medical experts urge caution, emphasizing the risks associated with dehydration and nutrient deficiency.

Insights from a US Dietitian

According to a US-based dietitian cited by the Times of India, fasting for 36 hours without water or food can have significant effects on the body. In the initial hours, the body uses glucose stored in the liver for energy. As the fast progresses, the body shifts to burning fat for fuel, which can result in weight loss.

However, the dietitian warns that dry fasting can lead to rapid dehydration, decreased blood pressure, dizziness, headaches, and impaired kidney function. The risks are especially high for individuals with underlying health conditions or those exposed to hot climates.

Potential Benefits and Risks

While some studies suggest that fasting can improve insulin sensitivity and reduce inflammation, there is limited scientific evidence specifically supporting dry fasting. The lack of water intake can quickly lead to dehydration, which may outweigh any potential benefits.

Experts recommend that anyone considering fasting consult with a healthcare professional beforehand, especially if they have pre-existing medical conditions or are taking medications.

Conclusion

Dry fasting remains a controversial weight loss trend. While it may lead to short-term weight loss, health professionals caution against its potential dangers. Safer, evidence-based approaches to weight management—such as balanced nutrition and regular exercise—are generally recommended.

Disclaimer:
This article is for informational purposes only and does not constitute medical advice. Dry fasting can be dangerous, especially for individuals with health conditions. Always consult a qualified healthcare provider before making significant changes to your diet or fasting routine.