So I have been doing something I never thought that I would do, which is experimenting with prolonged fasting and intermittent fasting to help me get to a point of optimal health. While I did intermittent fasting before, I mostly stuck to intermittent fasting periods of between 12 and 14 hours a day.

Even though when I first started intermittent fasting I did lose fat, I basically hit a plateau that lasted for a few years. After almost two years of trying to lose fat without success and in a desperate attempt to clear my acne, I decided to really push myself. I set a health challenge at the beginning of the year to become the optimal, healthiest version of myself in 2020 and started with a 30-day intermittent fasting challenge where I had to fast for 16 hours or longer every day. I also wanted to do a few prolonged fasts on top of fasting intermittently, as they are great for longevity and optimal health. 

To kick off my optimal health challenge, I started with a 72-hour fast a few days before the new year started. I went into 2020 fasting, partly because I wanted to do something really difficult, so that the rest of the year, whenever something felt like it was too difficult, I would be able to think back to my 72-hour fast and know that I can do anything, regardless of how difficult it is. 

After that, I did two more 48-hour fasts in January, did intermittent fasting in between, and just finished my third 48-hour fast. The reason why I chose to stick to a 48-hour fast and not do a 72-hour fast again is because a lot of the fat-loss benefits of fasting start to go away when you fast for longer than 48 hours, and your body will start to break down muscle if you fast for too long, which is not ideal if you are aiming for optimal health and want to improve your healthspan. You do not want to simply live longer, but you also want to be able to move around more when you are older, and having enough muscle mass is crucial.  

48-hour fasts also provide enough suffering. The thing is that now, if I feel like quitting during a 48-hour fast, I know that I have done this a few times before and know that I will be okay. I know that I just need to push through the discomfort of fasting and keep reminding myself of my goal of reaching a state of optimal health.  

What Are the Side Effects I Have Experienced During A 48-Hour or 72-Hour Fast? 

• Fatigue: could have seen this one coming. It makes sense that you will feel weak and tired during a fast because your body is not used to going this long without energy. 
• Food smells even better when I am fasting:  I do not know what it is, and perhaps it is connected to the mental clarity I feel when fasting, but my sense of smell seems to be better when I am fasting, which really sucks when you walk past a bakery or when someone is cooking meat closeby. 
• I could not work out as hard: I could not exercise at the intensity I normally do (which is not even that intense) when fasting for longer than 20 hours. Exercise while fasting is good, as it can help protect your muscles from being broken down and can increase autophagy, but luckily, it does not have to be intense exercise. 
• I felt anxious and jittery. This sucked a lot because even though my mind feels very clear when I fast for very long because I feel anxious and jittery, I am not that productive and struggle to keep still. My ADD is on steroids when I am doing a prolonged fast, so I do not think I will plan on being super productive again if I do a longer fast. Lesson learnt! Do not plan to do a lot of work when fasting. I do still manage to get a few things done, but I am not nearly as productive. 
• It is quite anti-social. I cannot really schedule dinners with family or friends when doing a prolonged fast unless I sit there and eat nothing and only drink coffee while other people are enjoying their food, but that is too much at times. I have visited people for a cup of coffee, and it was fine, as long as visits are not during mealtimes. 

So What Benefits Am I Getting From Fasting for 48 Hours? Why Would I Do Such a Thing? 

• Ageing: going for longer periods of time without eating is one of the best things you can do if you are aiming for longevity and want to slow down ageing. This is because it helps with cell recycling and regeneration, and ageing speeds up when these processes slow down. 
• Fat Loss: I noticed the biggest difference when it comes to fat loss when I started doing intermittent fasting and prolonged fasting. 
• Beautiful, healthy skin: As acne is an inflammatory condition and I also have a bit of scarring from previous breakouts, I wanted to start doing this more often to improve my skin health and hopefully get healthy, glowing skin.
• Stress resilience: fasting helps your body adapt to stress. By putting your body through hermetic stress like fasting and things like cold shock therapy, your body becomes better able to handle other stressful situations. 
• Confidence: you try feeling bad about yourself after you did not eat when you have a history of binge eating and still struggle to control yourself around food. 

What Does a 48-Hour Fast Do?

A 48-hour fast gives your body more than enough time to get rid of any glucose in your system, as well as clear out any damaged or senescent cells. Autophagy, the cell recycling process in your body, really starts to kick in after 16 hours. If you really want to clear your body of any unnecessary junk and really do a detox for optimal health, you want to be in a state of autophagy for quite a while. A 48-hour fast will help ensure that you are in autophagy for long enough to really have an impact. 

It will also help with fat loss. Your metabolic rate can increase during a longer fast, and because you are not eating, when you run out of fuel from the food you ate before your fast, your body will start to break down your own fat for energy. Fasting puts your body in a state of ketosis, where the body breaks down fat and turns them into ketones for fuel. 

One of the biggest benefits of doing a prolonged fast is that it lowers inflammation a lot. 

Is it Safe to Fast for 2 Days?

It is safe for most people to fast for two days, but it is recommended that you consult with your doctor before doing so. Diabetics need to be especially careful, and obviously, pregnant should not do it, as you need to consume enough food to support your baby and have a healthy pregnancy. 

How Much Weight Can You Lose On a 48-Hour Fast?

The amount of weight you can lose on a 48-hour fast depends on a lot of factors, such as:

1. How fat-adapted you were before the fast. Being fat adapted means that your body is used to burning fat for energy. If you follow a low-carb diet for a week or more before doing a 48-hour fast, your body will switch into fat-burning mode a lot quicker during a 48-hour fast.
2. Are you exercising and moving during your fast? The amount of weight you can lose depends on how much energy you burn during the fast. To lose weight, you need to burn more than you consume. If you just lie in bed during your fast, you will still lose some weight during your fast, but not nearly as much weight as if you were to be active for at least parts of the fast.
3. How much you eat after the 48-hour fast will also affect how much weight you lose due to the fast. Your body is likely to absorb whatever you eat after breaking your fast, and if you eat 3000 calories of junk food, you will undo a lot of the weight-loss benefits you received from doing it. If you break your fast with a healthy meal that is high in protein, then your body will absorb that protein and use it to replenish and repair cells. Just do not break your fast with a high-fat and high-carb meal. When you consume a lot of fat and carbs together, your body will store a lot more fat. Choose high-protein paired with either carbs or fat.

Does Fasting Put You In a State of Ketosis?

Fasting will put your body in a state of ketosis, so you do not have to follow a ketogenic diet to get the benefits of being in ketosis. It is even better when you pair a ketogenic diet with fasting. 

How Often Can You Do a 48-Hour Fast?

You do not want to do prolonged fasts too often, as they can put a lot of stress on your body. Once a month or once every few months is great, but I am currently doing a 48-hour fast every two weeks, as I am dealing with quite a few inflammation-related health issues and want to improve the appearance of my skin, and want to see if it will help, and I am also trying to lose fat. 

What Is a Good Way to Prepare for a 48-Hour Fast?

Plan to do your 48-hour fast when you will not have to be very social and watch other people eat. Also do not plan on having very productive days, as your energy levels can take a bit of a dip. I still work when I am fasting, but I do things like admin that do not require that much focus and that I can do at a relaxed pace.

Is Doing a 48-Hour Fast Once a Month the Secret to Optimal Health?

I think it is one of the secrets. There are a lot of things you can do to improve your health. But I do believe that intermittent fasting and prolonged fasting are incredibly powerful tools and that everyone should give it a try. 

How Do I Feel After Doing a 48-Hour Fast?

Honestly, I feel like a badass. Intermittent fasting and prolonged fasting have given me a lot more confidence. It is not always easy, and you definitely have a reason to be proud if you manage to fast. The first time I did a 16-hour fast, I felt unstoppable, now imagine how I feel after not eating for two days. I feel superhuman, and I am always really excited when I think about the benefits. 

I really feel like putting your body through challenges and stress like this can help with mental toughness. My mental clarity also improves a lot when I am fasting, and I understand how that can become addictive for people. When I am just doing intermittent fasting and I am fasting for 16 to 18 hours, I am always super productive before I break my fast. In fact, when I have finished writing this article, I am going to break a fast with a nice bone broth stew.