Costa Rica man loses weight with water fasting in 21 days: Is it safe?

A man lost 13 kilos in just 21 days with water fasting. Here is everything you need to know about how water fasting can help you lose weight.
water fasting
Water fasting helped a Costa Rica man lose weight but is it healthy? Image courtesy: Instagram| Lifestyle Limitless
Shruti Bhattacharya Published: 5 Jul 2024, 06:15 pm IST
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With so many diets and workout fads out there, a unique weight loss story has been going viral on the internet. A Costa Rican native, Addis Miller, recently rose to prominence for his innovative method of losing weight quickly and effectively. He claims to have shed 13 kilos in 21 days with water fasting. In a YouTube video, he shared his experience and insights, saying, “Earlier this year, I went on a 21-day water fast in Costa Rica. This event was life-changing for me, and I am delighted to share some of the most memorable experiences from my journey.” The man has gone viral for his weight loss transformation but that does not mean that the method he tried is safe.

Miller’s experience of trying water fasting

Miller said he was open-minded and was comfortable with the idea. For the first few days, he felt like his body was clearing out. Plus, he was feeling his belly was rumbling a lot and also was feeling tired. During the initial days, he was low on energy and it was challenging to stay true to the diet. Initially, he was drinking four litres of water each day, but he quickly discovered that he needed more water because his skin started to get dry and he noticed a bloodshot eye when he woke up in the morning. He also stated that the 14th day of the fast was a “pivotal moment” for him since it allowed him to connect with nature and sense what was around him. For him, the emotions and sensations were overwhelming. He said that on day 19, he wanted to fast for longer. He was not hungry. He felt amazing and spiritually renewed but his physical body was becoming weaker. He tried his best to become more energetic. He concluded by saying that this fast was life-changing for him.

In the Instagram post, he shares some benefits he experienced after trying water fasting, including:

  • Sense of smell recovered from suffering from long Covid.
  • Better memory
  • Hearing is better
  • Healthier relationship with hunger
  • Less digestive problems
  • Better taste
  • Lymphatic system functioning better
  • Fewer aches and pains
  • Clear and hydrated skin

While it may have worked for this man, is it safe for everyone to try water fasting for weight loss?

What is water fasting?

“Water fasting is a practice where you abstain from all food and consume only water for a set period, typically for a day,” says dietician Gauri Anand. Water fasting is a diet with no calories, where one only drinks 2-3 litres of water in a day. Following a water-fasting diet may cause changes in your body that could be good for your health, like burning fat and improving how your hormones work. While it is believed to be effective in the short term, you should not stick to it for a long time as it can lead to some side effects. However, a study published in the Global Advances in Health Medicine Journal found that doing water fasting may be beneficial for you.

Water fasting for weight loss: Does it really work?

The less you eat, the more you lose! It may sound simple but it isn’t as easy. When you do not eat anything solid, your body’s readily available source of energy (glucose from carbohydrates) gets depleted. To keep functioning, your body enters a state called ketosis. In ketosis, your body starts breaking down stored fat for energy, leading to weight loss, as found in a study published in the StatsPearl Journal. Plus, “if you are not consuming any food, you are taking in zero calories. This significant calorie deficit forces your body to tap into its reserves, which include fat, for fuel, resulting in weight loss,” says the expert.

Other benefits of water fasting

1. May reverse type-2 diabetes

Diabetes occurs when your cells become less sensitive to insulin, which helps your body convert food into energy and regulates blood sugar levels. According to experts, fasting may make your cells more insulin-responsive. A group of researchers did a short trial with 36 diabetics who fasted occasionally for three months. The study found that 90 percent of individuals lowered their diabetes prescriptions, including insulin, and more than half experienced diabetes remission (the state where your blood sugar levels become normal), as found in a study published in the Endocrine Society. However, more research is needed to prove whether water fasting helps or not in diabetes management.

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2. May lower blood pressure

Short-term water fasting is also thought to lower blood pressure. A 2022 study published in the Nutrients Journal found that 48 participants who were overweight or obese discovered a clinically significant reduction in both systolic and diastolic blood pressure after a 10-day water-only fast and five days of refeeding.

3. May trigger autophagy

Fasting may trigger autophagy, a cellular process where your body cleans out and recycles damaged cells, as found in a study published in the Ageing Research Review. This might contribute to overall health and potentially slow down signs of ageing, but more research is required to support the claim.

How to start water fasting?

You cannot suddenly start water fasting, you have to take a strategic approach to it. Here is a complete guide on how to prepare and start water fasting, as explained by the expert.

Preparation (3-4 days before beginning water fasting)

  • Reduce calorie intake: Slowly reduce portion sizes and eliminate processed meals, sugary drinks, and excessive caffeine. This helps to ease your body into a fasting condition.
  • Hydrate: Drink at least 2-3 litres of water per day. This prepares your body to rely entirely on water throughout the fast.
  • Choose a fasting window: Choose a timeframe that allows you to take rest and do some physical activity. Avoid fasting if you are anxious, sick, or overly sleepy.
    Inform those around you: Let your family, friends, and coworkers know you will be fasting to minimise unnecessary worries.

During the fasting period

  • Water is key: Drink just plain water, herbal teas (without sweeteners), or black coffee (with no cream or sugar). Aim for 2-3 litres of water per day.
  • Electrolyte support: Add electrolytes to your drink, especially for extended fasts. But consult your doctor for recommendations.
  • Listen to your body: Rest periodically and break your fast if you feel severe discomfort, dizziness, or vomiting.
  • Limit your activity: Avoid hard exercise. Light walks or moderate yoga are fine but prioritise rest.

Breaking the fast

  • Gentle reintroduction: Do not jump back into heavy meals. Start with easily digestible foods like bone broth, fruits, and vegetables. Gradually increase portion sizes and complexity over a few days.
  • Continue hydration: Maintain a high water intake even after breaking the fast.
    Listen to your body: Pay attention to your body’s signals and adjust your food intake accordingly.

Are there any side effects of water fasting?

Water fasting may be dangerous to some people, particularly those with the following conditions, as pointed out by the expert.

1. Eating disorders

Water fasting may promote disordered eating or initiate the binge-restrict cycle, as found in a study published in the Journal of Psychopathology and Clinical Science. This can lead to the onset of eating disorders, which can be bad for your overall health.

eating disorder
Regular water fasting may lead to an eating disorder. Image courtesy: Shutterstock

2. Pregnancy and breastfeeding

When you are pregnant or breastfeeding, your nutritional and caloric needs rise, and everything you do might have an impact on your unborn child. Fasting is not advised for anyone pregnant or breastfeeding.

3. Not advisable for type 1 diabetes

Water fasting is not advised for those with type 1 diabetes. If you have type 2 diabetes, you should always consult your doctor before fasting. If you have diabetes and go on a water fast, you risk developing hypoglycemia (low blood sugar). For people using insulin or other diabetes drugs, going without food may necessitate changing your medications, which you should never do without your healthcare provider’s permission. Fasting may assist with type 2 diabetes but always consult your doctor first.

Water fasting: Is it safe to follow?

Water fasting, which involves consuming just water, can be safe for certain people under particular conditions. Short fasts for a day with lots of fluids are usually tolerated well. However, it is vital not to continue water fasting if your body does not allow it or notice any unusual signs. It is important to consult a doctor before beginning, especially if you have any medical conditions. Also, it is not suggested for pregnant women, children, or those with specific medical conditions. Consider speaking with your doctor about intermittent fasting; it could be a safer and more sustainable way to attain your health goals.

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About the Author

Shruti Bhattacharya is a content writer and editor for over 2 years. She specialises in writing on a variety of topics such as wellness, lifestyle, beauty, technology and fashion. Her current focus is on creating factually correct and informative stories for readers. ...Read More

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