Woman Reveals What Happened to Her Body on an 18-Day Water Fast

A woman who went on a drastic liquid diet for more than two weeks has revealed to Newsweek exactly what happened to her body, as experts have warned against prolonged periods without food.

"I drank water and herbal tea for 18 days, but I made sure I had electrolytes daily," Emma Van Carlen, 34 said.

Van Carlen raved about the benefits a lengthy water fast had for her, although Newsweek discussed prolonged fasting with two doctors who strongly advise against it. The medical professionals warned that going without food for an extended period of time can result in an eating disorder or even death.

What Is Intermittent Fasting?

Intermittent fasting is a diet in which fasting and eating are alternated on a regular basis. There are several approaches to this type of fasting, according to Johns Hopkins Medicine, which may include fasting for 16 hours and eating during an eight-hour window. Alternatively, the popular 5:2 approach entails maintaining a normal schedule and eating in moderation five days a week, followed by consuming no more than 600 calories twice a week.

On its website, Johns Hopkins Medicine states longer fasting periods, such as 24, 36, 48, and 72 hours, are not necessarily better for you and may be dangerous. Going without food for an extended period of time may actually encourage your body to begin storing more fat in response to starvation.

While Dr. Ernie Vesta, a former emergency room and primary care physician, isn't completely against water fasting for weight loss, he wouldn't recommend any longer than 72 hours.

Dr. Vesta spoke to Newsweek about water fasting, stating his belief that any longer than three days is a "radical method of weight loss."

"I would not advise it," Vesta, chief medical officer at healthcare company Curally, said, who added that "a short term water fast would be considered one to three days."

"Your internal chemistry will change during that time. In place of food, our body mobilizes energy requirements from protein (your muscles) in addition to beginning to use some of our fat stores to maintain life.

"Since our basic energy needs to maintain life are satisfied by blood sugar, the liver helps to make new sugar from the mobilized protein, a process the medical community calls 'gluconeogenesis.'

"As a result, during any fast, you begin to use some muscle before transitioning to a starvation mode. In starvation mode your body uses primarily fat for energy to maintain life and spares muscle (beyond around 10 days)."

How Did Van Carlen's Body Respond Without Food?

Four years ago, Van Carlen, who is originally from Sweden, began intermittent fasting ahead of her wedding, losing 30 pounds within seven months.

She achieved the results by fasting for 16 hours per day and eating one or two meals per day within an eight-hour time slot. Followed by the lengthy water fast that helped her lose 17 pounds and she says cleared her skin of acne.

Now, twice a year, Van Carlen, a fasting coach, completely abstains from food for three to five days.

"The first three days were the toughest, as I had headaches and felt sick," she told Newsweek about her 18-day experience in 2021.

While she eschewed food, she consumed electrolytes daily, including "potassium, sodium, and magnesium are essential when fasting to help prevent nausea, headaches, and weakness."

Van Carlen attributed initially feeling sick to her body stopping "burning food for fuel and started burning fat instead."

"We aren't used to it, so it can make us feel a little bit off. Then I started to level out, and any side effects went away. On the 8th day, I felt more energetic and less hungry," she explained.

One study, published in the peer-reviewed journal Nutrition Reviews in June 2023 revealed "prolonged fasting for 5–20 days produces potent increases in circulating ketones, and mild to moderate weight loss of 2–10 percent."

The group of researchers from the Department of Kinesiology and Nutrition, University of Illinois at Chicago, looked into the efficacy and safety of prolonged fasting.

They found that one-third of the weight loss is fat mass, and the other two-thirds is lean mass. The paper states it is concerning that an extended fast may accelerate the breakdown of muscle proteins, as suggested by the significant loss of lean mass.

Fasting for an extended period of time was consistently associated with a decrease in blood pressure. Some studies have also discovered that high LDL cholesterol levels, as well as high levels of a type of fat in your blood that is used for energy, have been reduced.

Van Carlen explained how she navigated feelings of hunger by going on daily walks for an hour in a bid to keep herself distracted.

"Hunger comes and goes in waves; it doesn't just worsen as the days go by. Usually we get hungry around breakfast, lunch, and dinner because we have trained our bodies to expect food at those times," she said. "I just pushed through the hunger pains and drank peppermint tea to suppress them."

Halfway through the fast, Van Carlen began to miss the social aspect of eating as she was missing out on meal times with her partner.

Van Carlen shared her experience in a TikTok video earlier this year, racking up over 684,000 views. During the clip, she states her mind began "playing tricks" on her between days 11 and 14. She kept telling herself to quit, but she didn't.

However, she admits the final three days were up and down. On the final day, she broke the fast with bone broth and avocado, and slowly introduced solid foods. Van Carlen described the long fast as "truly transformative" for her.

The Dangers of Fasting

Newsweek also spoke to Dr. Olalekan Otulana, a substance misuse and addiction physician. Like Vesta, he doesn't advise going without food for as long as Van Carlen did.

"Water-only fasting is an absolute cessation of food consumption while consistently consuming two to three liters of water per day. This type of fasting is widely-believed to improve health and could help motivate a healthy diet and lifestyle changes. It has been found that this type of intervention stimulates physiological effects that are potentially favorable to health," he said.

Although Otulana told Newsweek a fast that is any longer than 72 hours may "potentially compromise the safety of the person and could result in health complications."

"Over a long fasting period, you might develop other nutrient deficiencies as well, such as scurvy," he said.

His biggest concern about an extended fast is the risk of developing an eating disorder propensity.

"When prolonged for an extended period of time, the water fast runs the risk of changing your psychology around food—especially if the person fasting hasn't eaten properly in 18 days. "There also remains the challenge of re-introducing food to the person who has undergone the water fast. When the person is re-fed after 18 days of water fasting, there is the potential for detrimental effects on the body," Otulana said.

Fasting Isn't for Everyone

While Van Carlen advocates fasting for a living, she acknowledges that it is not for everyone and urges people to check with a medical professional prior to attempting it.

"Fasting is safe for most healthy individuals, but if you have an underlying health issue like diabetes, then you must consult a doctor," she told Newsweek. "If you are a healthy person and if you are doing it in a healthy way, fasting is safe. You must listen to your body for signs of distress, like fainting and vomiting. If you are experiencing any of this, then you are doing it wrong.

She added: "Fasting can be used as a helpful tool that can help reduce inflammation in the body. It's like a spring clean for my body. I used to have cystic acne, but it spontaneously went away after fasting. Fasting isn't suitable for people with eating disorders. It's important for everyone to approach it with an educated mindset.

"Fasting should never be used as a punishment for yourself or to overcompensate for eating something—that is, when you are in a dangerous territory. I always approach fasting with a calm mind."

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