10 day water fast

Introduction

10 day water fast. Fasting has been practiced for millennia for religious, ethical or health reasons. Now, it is a popular therapeutic strategy to prevent chronic disease and a huge problem during some extraordinary circumstances in which people may be unable to obtain anything edible for days. To endure prolonged fasting, the body undergoes important physiological adjustments to keep its function. However, whether severe fasting is safe or leads to a new energy metabolic homeostasis is largely unknown.

The changes in modern lifestyles and excessive food intake increase the risk of developing chronic diseases. The first therapeutic strategy to prevent these diseases is a lifestyle change such as dietary interventions and physical activity more than pharmacological treatments . In humans, fasting is characterized by consciously eating no or minimal amounts of food and caloric beverages for periods that typically range from 12 h to weeks . Emerging discoveries drive a growing public perception that fasting is beneficial for many aspects of human health and shows great potential for the therapy of metabolic diseases . Although the prevalent fasting models such as intermittent fasting (IF), alternative day fasting (ADF) and time-restricted feeding (TRF) have been demonstrated to potentially prevent diseases and manage body fitness with minor side effects , the ameliorative effects of fasting show great diversities mainly due to individual differences and various short-term complete fasting (CF) models, which influence its large-scale application to an array of diseases.

Taken together, although ketone bodies, deposited fat and gluconeogenesis allow most human beings to survive 30 or more days in the absence of any food, there are still few human being experiments that explore the systematic changes of prolonged fasting on a healthy body. We proposed that the short time of CF is the main cause of different or individual benefits from fasting. Then, a 10-day CF human experiment was conducted under controlled conditions to systematically estimate its safety, tolerance and time effects on health, psychological mood and brain functions. Our previous reports have presented that 10-day CF affected subjective sensations but not cognitive abilities, which was associated with the energy substance switch in the middle of CF , and previous fasting experience was important to prevent negative feelings during prolonged fasting . In the present, we minutely depicted the time effects of 10-day CF followed by refeeding on body health, physiological and nutritional status assessed by pulse, blood pressure, body weight (BW), blood glucose and ketones, body composition and nutritional and biochemistry indexes to evaluate health risks and the application advantage of long-term CF.

Materials and Methods

2.1. Participants

We performed a 10-day water-only fasting in male adults under medical supervision conditions with detailed descriptions in our previous publications . In brief, 60 interested Chinese participants were invited for further screening and 44 participants dropped out due to age, weight, BMI, underlying health conditions or religious beliefs. Three dropped out for personal reasons before the start of the experiment. Finally, 13 male participants undertook water only ad libitum drinking during the fasting period in a controlled laboratory building, accompanied with a mild-intensity lifestyle program. The exclusion criteria included: history of eating disorders or any chronic illnesses, including diabetes mellitus, cancer, cardiovascular disease, metabolic diseases and tobacco or alcohol dependence, which were reviewed during a complete medical examination before the experiment.

2.2. Study Design

The study was approved by the Ethics Committee of the Space Science and Technology Institute (Shenzhen) (SISCJK201805001) and followed the ethical standards of the 1964 Declaration of Helsinki and its later amendments. All participants signed their written informed consent form and were informed by detailed experimental design and process of this study before the start of the experiment. A 22-day experiment was divided into four phases (3-day Baseline (BL), 10-day CF, 4-day CR and 5-day Full Recovery (FR). During the second phase, the participants were only permitted to drink Nongfu Spring water (including Ca ≥ 400, Mg ≥ 50, Na ≥ 80, K ≥ 35, metasilicate ≥ 180 µg/100 mL) ad libitum and performed normal ambulatory activities in a health research building. In the third phase, the participants were gradually given increased amounts of food to protect their digestive system after CF. During the final phase, the participants were allowed to return to their normal eating habit.

What is water fasting?

Water fasting is a type of fast during which you cannot consume anything besides water.

Most water fasts last 24–72 hours. You should not follow a water fast for longer than this without medical supervision.

Here are a few reasons why people try water fasting:

• religious or spiritual reasons
• to lose weight
• for “detoxing”
• for its health benefits
• preparing for a medical procedure

The main reason why people try water fasting is to improve their health.

How do you water fast?

There are no scientific guidelines on how to start water fasting.

However, several groups of people should not water fast without medical supervision.

This includes people with gout, diabetes (both types 1 and 2), and eating disorders, older adults, people who are pregnant, and children If you have never water fasted before, it’s a good idea to spend 3–4 days preparing your body for being without food.

You can do this by eating smaller portions at each meal or by fasting for part of the day.

Water fast (24–72 hours)

During a water fast, you are not allowed to eat or drink anything besides water.

Most people drink two to three liters of water per day during a water fast.

The water fast lasts for 24–72 hours. You should not water fast for longer than this without medical supervision because of health risks.

Some people may feel weak or dizzy during a water fast and may want to avoid operating heavy machinery and driving to avoid causing an accident.

Post-fast (1–3 days)

After the water fast, you should resist the urge to eat a big meal.

This is because eating a large meal after a fast may cause uncomfortable symptoms.

Instead, break your fast with a smoothie or smaller meals. You can start introducing larger meals throughout the day as you feel more comfortable.

The post-fast phase is especially important after longer fasts. This is because you may be at risk of refeeding syndrome, a potentially fatal condition in which the body undergoes rapid changes in fluid and electrolyte levels.

This phase normally lasts a day, but people who fast for 3 or more days may need up to 3 days before they feel comfortable eating larger meals.

Is water fasting worth it?

In short, probably not.

There’s very little evidence that water fasting is a healthy approach to managing health or losing weight.

Weight loss is inevitable if you’re eating nothing, but we know that moving toward a healthier lifestyle often involves small, simple changes that are realistic and manageable. 

What’s more, the weight loss likely stems from the body releasing glycogen (energy) stores from the liver and muscles. These stores hold a lot of water.

Meanwhile, there’s been little research into how quickly people regain the weight lost during an extreme fast.

Overall, water fasting can be hard to sustain, even in the short term. And understandably so. 

It’s also likely that any side effects of water fasting would impact your day-to-day activities, at work or school and in your free time. 

Finally, you’re more likely to feel tired, so you might not feel like staying active. And we know that physical activity is key for maintaining your overall health and a moderate weight.

Risks of water fasting

Water fasting carries risks, including side effects such as mood changes, migraine headaches, and disordered eating. It can make you feel physically and mentally drained, too.

And this type of fasting can be particularly dangerous for certain people. For example, pregnant people, those with type 1 diabetes, and anyone who needs to take medication with food should avoid it.

Unlike intermittent fasting, which we’ll touch on later, water fasting is at the extreme end of the fasting spectrum, in part because people often try it for long periods.

Potential benefits of water fasting

Both human and animal studies have linked water fasting to a variety of health benefits.

Here are a few health benefits of water fasting.

May help lower blood pressure

Research shows that longer, medically supervised water fasts may help people with high blood pressure lower their blood pressure. in 48 people with overweight or obesity found that water fasting for an average of 17 days under medical supervision led to reductions in systolic blood pressure.

It was also associated with improvements in levels of LDL (bad) cholesterol and inflammation.

Similarly, another review concluded that water fasting could significantly reduce blood pressure levels and body weight in people with high blood pressure.

Still, more research is needed to evaluate the link between short-term water fasts (24–72 hours) and blood pressure.

Will water fasting help you lose weight?

Like other types of fasting, water fasting can help you lose weight.

However, it comes with plenty of health risks.

If you want to reap the benefits of fasting but also want to lose weight, intermittent fasting and alternate-day fasting are probably more effective approaches than water fasting for 24–72 hours.

These fasts provide similar health benefits but can be followed for much longer periods, as they allow you to eat food, decreasing the risk of nutrient deficiencies.

Benefits from personal experience

To give you a background of my body: I’m a 27-year-old cisgender woman with a 21 BMI. I’ve never had health complaints or operations. Before my first fast, doctors said I’m healthy.

But I wasn’t healthy. I ate a glass of Nutella a week, hated cooking, and felt addicted to eating. Plus, I didn’t like my body. I worried about gaining weight and eating too much five times every day. I felt trapped in a vicious circle of negative self-chatter.

This is how fasting changed my life:

• Food Appreciation: I started to enjoy cooking and seeing food as nourishment for my body rather than a threat.
• Healthy Diet: After fasting, I didn’t like the taste of sugar and processed foods anymore. I changed my diet, but not because I forced myself. It felt only natural to become vegan and choose fresh ingredients.
• Food Patience: I’m no longer hangry. I know my body can survive days without food, and another hour won’t hurt me.
• Body Appreciation: I felt gratitude for my healthy body and mind. What I took for granted suddenly felt special. The gratitude always remains for some months after the fasting period.
• Higher Energy Levels: I had high energy levels before my first fast. But after fasting, I’m able to tackle anything I previously avoided.
• A Clear Mind: I felt laser-sharp focus. I could look at my life from a bird’s eye perspective. I saw toxic friendships and felt the need to end them. I changed my phone habits. I decided to become self-employed. A lot of major life decisions happened as a result of my fasting experiences.

Other friends had similar experiences. Not all turned vegan and not everybody started to love their bodies. But all of them reported a greater appreciation of mind and body.

Here are 5 FAQs about a 10-day water fast: