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Dry Fasting: Does It Boost or Endanger Our Health?
April 15, 2020
Dry fasting is commonly practiced for religious, spiritual or health-related reasons. In addition to improving self-discipline and awareness, proponents claim that it may also be associated with a wide range of benefits, including increased weight loss, better blood sugar control and more.
However, there are also several serious side effects to consider as well. In fact, prolonged fasting can ramp up the risk of dehydration, nutritional deficiencies, weakness and fatigue.
This article will take an in-depth look at a few of the purported benefits of dry fasting, along with some reasons you may want to consider other types of fasting instead.
What Is Dry Fasting?
Fasting is a practice that involves abstaining from food for a specific period of time. With most forms of fasting, liquids like water, coffee and tea are usually permitted. However, with dry fasting, all foods and liquids are restricted during the fasting window.
Dry fasting is commonly used in religious or spiritual practices, including Ramadan, a month-long Muslim holiday in which people fast every day from dawn to sunset. Fasting is also thought to improve self-discipline, increase feelings of gratitude and enhance faith and spirituality.
Some also choose to fast for health reasons, including increased weight loss and fat-burning. This is because there are a few main dry fasting stages that occur when you abstain from eating altogether.
When your body runs out of glucose (sugar) to use for energy, it will begin breaking down glycogen stores instead. After the glycogen stores are depleted, it starts converting fat into ketones, which can be used as an alternative fuel source for the body.
Other purported health benefits of dry fasting include decreased inflammation, improved blood sugar levels and enhanced cell regeneration.
Additionally, because it’s more extreme than other types of fasting, some believe that dry fasting can amplify or speed up the benefits of fasting. However, research is limited on whether or not completing a dry fast offers any added benefits over other forms of fasting.
Types/Varieties
There are several different types of dry fasting, each of which varies in terms of its specific length. Here are a few of the most common types:
- Periodic Fasting: This type of fasting requires you to limit food and water intake for a specific number of days.
- Intermittent Dry Fasting: This form of fasting involves cycling between periods of fasting and eating, with fasting windows usually lasting between 16–20 hours.
- Alternate-Day Fasting: With this type of fast, you should abstain from food and liquids every other day.
- Eat Stop Eat: This method requires dieters to fast on one to two days non-consecutive days per week. On other days during the week, you should follow a normal diet.
Vs. Water Fasting
Compared to water fasting, dry fasting is much more restrictive. While water fasts permits the consumption of water (and sometimes other beverages like coffee or tea) during the fasting window, a dry fast requires you to restrict all foods and drinks.
While some claim that the dry fasting results are much faster, there’s limited evidence to support this. For example, one review published 25 articles and found that both types offered similar benefits in terms of weight loss and overall health.
Water fasting is also much more flexible, easier to follow and associated with fewer adverse side effects. If implemented properly, certain types of fasting, like intermittent fasting, can be safely incorporated into a healthy routine with minimal risk of side effects.
Potential Benefits
Proponents of dry fasting claim that abstaining from liquids can amplify the benefits of fasting even more. Here are a few of the purported benefits of dry fasting and the science to support it.
1. Decreases Inflammation
Although acute inflammation is a normal part of the immune process, sustaining high levels of inflammation long-term can increase the risk of chronic disease. Fasting has long been used to reduce inflammation and protect against cell damage. In fact, studies show that fasting can suppress the expression of inflammatory markers and decrease oxidative stress.
Keep in mind, however, that additional studies are needed to determine whether or not fasting from liquids may offer any additional benefits over other forms of fasting and how this may impact the development of chronic disease.
2. Boosts Weight Loss
Many people incorporate fasting into their routine to help boost weight loss and fat-burning. In addition to decreasing overall food intake by limiting the period of time during which food is consumed, fasting also forces the body to use up fat for fuel instead of sugar. In clinical studies, intermittent fasting has even been shown to improve body composition by increasing both weight loss and fat loss.
Note that while research suggests that fasting in general may be beneficial for weight loss, current evidence on the link between dry fasting and weight loss rates is lacking. Further studies should be conducted to evaluate whether dry fasting is more effective for weight loss than other types of fasting.
3. Promotes Cell Turnover
Autophagy is a natural process in which the body clears out and replaces damaged cells. Not only can this process help slow signs of aging, but it may also aid in the prevention of chronic conditions, including cancer, diabetes, liver disease and neurodegenerative disorders like Alzheimer’s.
In animal models, fasting has been shown to help induce autophagy, enhance immune health and increase cell regeneration. Although more human studies are needed on the effects of dry fasting on autophagy, one analysis published in Ageing Research Reviews concluded that “evidence overwhelmingly suggesting [sic] that autophagy is induced in a wide variety of tissues and organs in response to food deprivation.”
4. Improves Blood Sugar Control
Some research has found that fasting could be especially beneficial for those with diabetes. For instance, one study in 10 people with type 2 diabetes found that intermittent fasting led to decreased caloric intake, increased weight loss and significant improvements in blood sugar levels.
What’s more, fasting could also help protect against insulin resistance. Insulin is the hormone responsible for transporting sugar from the bloodstream to the tissues where it can be used as energy.
Having high levels of insulin circulating in the blood can decrease the body’s sensitivity to insulin, which can impair your ability to regulate blood sugar levels efficiently. According to one study out of Malaysia, intermittent fasting not only improved blood sugar levels and increased weight loss, but it also helped effectively enhance insulin sensitivity in healthy adults as well.
Related: Intermittent Fasting on Keto: Important or Overhyped?
5. Speeds Up Results
Because dry fasting is more restrictive than regular fasting, many people believe that it can speed up results. However, it remains unclear whether or not there are any added benefits of dry fasting compared to other forms of fasting.
One review published in 2019 compared the effects of dry fasting with other types of fasting, including time-restricted eating. Interestingly enough, researchers noted that both types of fasting were effective for weight loss and offered similar health benefits. Still, additional studies are needed to evaluate if dry fasting may affect the rate at which results are obtained.
Dangers and Side Effects
Although there are several purported benefits of dry fasting, there are several dry fasting dangers to consider as well.
Like other types of fasting, dry fasting can cause side effects like hunger, decreased energy levels, mood changes, headaches and brain fog. However, dry fasting is particularly dangerous because it requires you to restrict all liquids as well as food, which can cause dehydration and electrolyte imbalances. While the human body can survive several weeks without food, it can only survive a few days without water.
If fasting is prolonged or repeated several times within a short period, it can cause serious side effects, including dehydration, nutritional deficiencies, binge eating, kidney stones and fainting. In severe cases, dry fasting can even lead to death.
If you have any underlying health conditions, you should consult with a healthcare professional to determine if fasting is right for you. Fasting is also not recommended for children, teenagers, those with a history of disordered eating and women who are pregnant or nursing.
Final Thoughts
- What is dry fasting? Dry fasting is a practice that involves abstaining from all foods and drinks, often for religious or health reasons.
- There are several different types available, including periodic, intermittent and alternate-day fasts.
- Some of the purported dry fasting benefits include decrease inflammation, increased weight loss, enhanced cell turnover, improved blood sugar levels and faster results.
- However, completing a dry fast can also cause serious side effects like dehydration, nutritional deficiencies and kidney stones.
- Compared to water fasting, dry fasting is also much more restrictive, dangerous and difficult to follow.