Dehydration, ADH, Vasopressin, and Dry Fasting


ADH or Vasopressin is the hormone that helps the body conserve water during a dry fast. Let's explore dry fasting and dehydration more.

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ADH, also known as vasopressin, is a hormone produced by the hypothalamus in the brain and stored and released by the posterior pituitary gland. It plays a pivotal role in maintaining the body's water balance.

Dehydration is a condition that occurs when the body loses more water than it takes in. This can happen due to various factors, such as excessive sweating, vomiting, diarrhea, or not drinking enough fluids. When the body is dehydrated, it tries to maintain its water balance through a complex system of hormones and feedback mechanisms. One of the key hormones involved in this process is Antidiuretic Hormone (ADH), also known as vasopressin.

What is ADH?

ADH is produced by the hypothalamus in the brain and stored and released by the posterior pituitary gland. It plays a pivotal role in maintaining the body's water balance. When the body is dehydrated, osmoreceptors in the hypothalamus detect the increased osmolality (concentration) of the blood. These receptors then stimulate the production and release of ADH. Once released into the bloodstream, ADH acts on the kidneys, prompting them to reabsorb more water and return it to the bloodstream. This action reduces urine volume and conserves water, ensuring that the body doesn't lose more water when it's already dehydrated. The net effect of increased ADH is the production of a smaller volume of more concentrated urine, which is darker in color. On the flip side, when the body is well-hydrated, ADH secretion decreases, leading to the production of a larger volume of dilute, light-colored urine.

This is important, as I do believe that the longer you dry fast you continuously use up more water than you create. So there is a balance that needs to be struck. The question is - at what point do we reach maximum therapeutic dehydration? Where does the line get drawn? Even if increased dehydration triggers stronger healing, we need to establish a safety zone where the damage outweighs the positive healing mechanisms. Currently, following Specific Gravity in a urine test, urine color along with dry mouth can give us a bit of an indication. Ingesting water to balance disrupts the homeostasis mechanisms, so it is highly discouraged. Speeding up dehydration through the first days of the fast is an option, albeit a scary one, and would necessitate following dehydration levels more closely, and then slowing down the activity levels.

During dry fasting, there is no intake of water, and the body is at a higher risk of dehydration. As dehydration starts to set in, the increased blood osmolality due to reduced water content prompts the hypothalamus to stimulate the release of more ADH. With higher ADH levels, the kidneys reabsorb as much water as possible, minimizing water loss through urine. This process is vital during fasting, as the body is trying to conserve every drop of water it has.

However, it is essential to use ADH levels as a tool, not an endpoint. If ADH levels are persistently elevated, it's an indication that the body is in a dehydrated state. Dry fasting shouldn't be prolonged to a point where it becomes detrimental to health. Everyone's body is different, and what might be a normal ADH level for one person during fasting might be different for another. It's crucial to understand personal baselines and work with a health professional to interpret any changes.

Prolonged stimulation of ADH (due to extended fasting or dehydration) can also lead to other effects like constriction of blood vessels. This constriction can increase blood pressure, which is one of the reasons why consistent and prolonged dehydration may not be good for cardiovascular health.

Monitoring ADH During Fasting

If someone is undergoing therapeutic dry fasting under the guidance of a health professional, periodic testing of ADH levels might be recommended to monitor the body's response. However, testing serum osmolality along with electrolytes and ADH levels would be fantastic. This is not possible for most dry fasters, however, alongside objective tests, maintaining a daily journal of symptoms like the color and volume of urine, thirst levels, and any feelings of dizziness or lightheadedness can provide context. No one can tell you for certain if going past 5 days of dry fasting will have any permanent negative damage or if the stem cell activation is able to fully heal any damage incurred.

Specific Gravity, Dehydration, and Serum Osmolality

Specific gravity is a measure of the density of a substance compared to the density of water. In the context of urine testing, specific gravity can be used to assess the body's hydration status. When the body is dehydrated, the kidneys reabsorb more water, resulting in a higher specific gravity of the urine. On the other hand, when the body is well-hydrated, the kidneys excrete more water, resulting in a lower specific gravity of the urine. I always advise anyone I consult with to keep track of specific gravity, urine pH, and ketones. This can be done with the urinox-10 urine test strips quite easily.

Serum osmolality is another test that can be used to assess the body's hydration status. It measures the concentration of particles in the blood, such as sodium, glucose, and urea. When the body is dehydrated, the serum osmolality increases, indicating a higher concentration of particles in the blood. On the other hand, when the body is well-hydrated, the serum osmolality decreases, indicating a lower concentration of particles in the blood.

Dry Fasting and Therapeutic Dehydration

Dry fasting has been used for centuries as a spiritual and therapeutic practice. Proponents of dry fasting believe that it can help the body heal and rejuvenate by triggering various physiological processes, such as autophagy (the body's natural process of breaking down and recycling old or damaged cells) and increased production of human growth hormone (HGH). There is also the ability of the blood to pull out toxins and more from cells like lipofuscin due to the osmotic effect. These are currently theories and we don't know where the line should be drawn for therapeutic dehydration. My protocols focus on 5-day dry fasts because I believe they reach therapeutic levels of dehydration without going too far. Check out the Scorch protocol for Autoimmune illnesses here.

However, it is essential to approach dry fasting with caution, especially when it comes to prolonged or extreme forms of fasting. While there may be potential benefits, there are also risks involved.

Q: How long can you dry fast before dehydration becomes dangerous?
: The risk of dehydration significantly increases after 48 hours.

Q: What are the early signs of dehydration during a dry fast?
: Common signs include dark yellow urine, dry mouth, fatigue, dizziness, and rapid heartbeat. It's crucial to listen to your body and rehydrate if necessary.

Q: Is dry fasting safe if I'm just doing it for 24 hours?
: Many people report completing 24-hour dry fasts without severe issues.

Q: How does dry fasting affect kidney function?
: Dry fasting can help detoxify the kidneys, but prolonged fasting without hydration might strain the kidneys. It's important to approach it gradually and listen to the body.

Q: Can dry fasting lead to permanent dehydration damage?
: While the body can recover from short-term dehydration, repeatedly exposing it to severe dehydration might lead to long-term health complications, including kidney damage. This is why daily intermittent dry fasting is not recommended. Controlled fasts a few times a year are done therapeutically instead.

Q: How should I break a dry fast to ensure I don't get too dehydrated?
: Gradually reintroduce fluids. Start with small sips of water, and then progressively increase the amount. After rehydrating for a safe length, you can start with very light and digestible foods.

Q: Are there any benefits to dry fasting over water fasting when considering dehydration risks?
: Dry fasting offers more potent detoxification benefits and fat loss in a shorter period, but it comes with a higher risk of dehydration compared to water fasting.

Q: How can I prepare my body for a dry fast to minimize dehydration risks?
: Hydrating well is recommended in the days leading up to the fast, reducing caffeine and alcohol intake, and ensuring a healthy diet with plenty of electrolytes. Jumping in from a low-carb diet introduces dehydration earlier, and should not be performed for dry fasts longer than 5 days. For those that don't require a low carb diet for health reasons - Check out the juice prep protocol.

Q: Is it safe to exercise while dry fasting?
: Intense exercise increases dehydration risks during a dry fast. However, light exercise may stimulate better lymphatic clearing and more metabolic water production. You would be advised against strenuous activities while dry fasting.

Q: Can dry fasting cause electrolyte imbalances?
: Yes, without water and food intake, the body can't replenish lost electrolytes, however dry fasting research papers have indicated that the body is able to maintain healthy electrolyte levels during a 5-day dry fast by activating homeostasis mechanisms.

Yannick Wolfe

15 Years of Fasting Experience, Ex-ME/CFS, Ex-Long covid. Tech Consultant, Molecular biologist, Father, Researcher, Experimenter.

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