Water fasting is a short-term food intake restriction practice that only includes water ingestion.
Fasting is an extreme diet that has been adopted for thousands of years, especially by a few religions and cultures.
More recently, Western civilizations embraced water fasting to lose weight quickly.
Although it has been scientifically proven to have health benefits, it's important to stress that it has risks and does not apply to everyone.
So, what exactly is water fasting?
Water fasting is a type of short-term fasting that lasts from 24 to 72 hours and restricts the ingestion of nutrients to nothing but water.
The diet should be prescribed and monitored by a doctor and followed by a healthcare professional.
Besides religious reasons and weight loss, the method can be used for detoxing and before a more or less complex medical procedure.
Health Benefits
The human body needs water to survive.
Men are advised to drink around 3.7 liters of liquids per day, while women should ingest roughly 2.7 liters.
Most people embrace water fast for health reasons, primarily diabetes, heart disease, and Alzheimer's, and to lower the risk of a few types of cancer.
The drastic practice is also associated with cleaning damaged cells and regenerating new ones, a process known as autophagy.
The sensitivity to insulin and leptin improves, and the fall of blood pressure to healthy levels are some of the health benefits of water fasting.
The lemon detox cleanse is similar but includes other ingredients (cayenne pepper and maple syrup) and could last up to seven days.
Water fasting could have multiple negative consequences on human health.
Pregnant women, older adults, people with type 2 (T2D) and type 1 diabetes (T1D), gout, or eating disorders, and children should not adopt it without medical advice and supervision.
Getting Your Body Ready
The water-only diet requires a previous body preparation for the food restriction scheme.
Ideally, you should slowly reduce the food intake on the previous days and eventually fast for part of the day.
Once you're ready and get the green light from your doctor, it's time to start drinking two to three liters of water daily.
The body will respond to the new physical regime a few hours after beginning the water fasting program.
The most common symptoms include fatigue, dizziness, weakness, headaches, muscle aches, constipation, and low blood sugar.
The more physical exercise you do, the harder it will be to complete your water-only diet.
Once the fasting session ends, avoid eating heavy meals as it might make you feel uncomfortable, nauseous, and sick.
The best way to resume your regular diet is to start introducing yogurts, fruit juices, and smoothies before slowly eating larger meals.
In the first 24 hours, the goal is to avoid potentially serious complications from rapid shifts in fluid and electrolyte levels, a condition named refeeding syndrome.
If your water fasting program lasts for 72 hours or more, you'll need around three days before increasing your daily food intake.
Risks and Dangers of Water Fasting
Although it has potential benefits for human and animal health, a diet based on water intake can be dangerous and jeopardize your life.
If your main goal is to drastically reduce calorie consumption, you should know that you might lose essential things to the human body, i.e., good carbs and muscle mass.
According to several studies, water fasting makes us lose around two pounds (0.9 kilograms) per day on a single to three-day water fast.
Paradoxically, water fasting could lead to dehydration and nutrient deficiencies.
The reason is that around 20 to 30 percent of our daily water intake derives from the food we eat - meat, fish, fruit, vegetables, etc.
So, despite drinking from two to three liters a day, it might not be enough to replenish your water needs.
There's also another health issue connected with water fasting - it is called orthostatic hypotension.
It results in a drop in blood pressure and, consequently, dizziness, fainting, lightheadedness, and extreme physical weakness.
Last but not least, a long-term water fast program could aggravate medical conditions you might already have, including an increase in uric acid production and bulimia.
Remember that each person has their own specific health issues, needs, and lifestyle, so make sure to discuss the water-only practice with your doctor, as it should be medically reviewed by a healthcare professional.
They could suggest alternate-day fasting or intermittent fasting as the right option for your body.