---
title: "Weight Gain During Fasting: Causes, Fixes, and Lab Tests"
description: "Weight gain during fasting is often water retention, stress hormones, or thyroid slowdown. Targeted blood tests available at Quest—no referral needed."
canonical: "https://www.vitalsvault.com/symptoms/weight-gain-during-fasting"
last-updated: 2026-08-22
---

# Weight Gain During Fasting: Causes, Fixes, and Lab Tests

> Weight gain during fasting is often water retention, stress hormones, or thyroid slowdown. Targeted blood tests available at Quest—no referral needed.

---

Canonical HTML: https://www.vitalsvault.com/symptoms/weight-gain-during-fasting
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