Prolonged Fasting For Weight Loss In Older Adults

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There are many different types of fasting exercises that become popular from time to time. If you haven’t heard of it already, intermittent fasting is a thing that a lot of people, including celebrities, have vouched for from time to time. A vital part of intermittent fasting is the timing of meals.

But if you are planning on taking it to the next level, prolonged fasting is the one you want to look at. It is worth mentioning up top that this is an extreme form of fasting. And while it has some scientific backing, it is not for everyone and might not always fetch the results you hope.

Before we start, it is essential that if you decide to commit to a prolonged fast that you do it with the assistance or your Medical Practitioner. There are great benefits from this type of fasting, but only if it is done correctly.

Here’s a low down of its benefits and potential side effects. You decide.

What Is Prolonged Fasting?

This form of fasting essentially is about restricting the intake of calories to an extreme level. It can last from two to five days and go up to two weeks. You only consume liquids like water or plain tea and black coffee too.

Experts say that those who want to try this should start with intermittent fasting which is less intense. Once you know your way around it, you can extend the time periods gradually and reach prolonged fasting.

This will give your body the chance to adjust to the regimen you are putting it through. Now, the human body can handle this type of deprivation of food for a long period. The specific time period depends on the person in question.

The longest of such recorded incidents has been 382 days, but there have been instances where people have died just after 26 days.

So, if you are thinking about giving this a go, you might want to start with a 12-hour eating:12-hour fast and then move on to 24 hours and then escalate it to two days which is when it qualifies to be prolonged fasting.

Prolonged fasting comes with the objective of stressing the body over many days to make healthy changes that start at the cellular level. This should always be done under the supervision of a medical professional.

You should follow routines that still provide your body with healthy foods specific to this style of fasting so that you reap the benefits and not fall prey to fads.

Its Connection To Weight Loss

When you restrict the intake of calories, you theoretically make the body lose weight. This happens because the body will metabolize the stored fats it has to produce energy since it is not getting any new food. This process is called ketosis and there are a few diets around that concept too.

But it is important to know that your insulin and blood glucose levels experience a drop around 12 to 16 hours after you started the fast. We say “in theory” because this is not a standard for everyone since the needs of each body are different.

Prolonged Fasting For Weight Loss

When your body is in this state of fasting, it will no longer use the glucose that you get from food to produce energy. Instead, it will use the fat reserve and as a result, it will produce ketones that the brain will oxidize to carry out its functions.

When you get back to eating, the pathways that signal nutrients to get back on track will be reactivated and the process of ketosis will take a back seat. This method is said to improve your metabolism, improve the immune functions of the body and reduce inflammation.

So, it is possible to lose weight following this process in a way that suits the needs of your specific body type. Needless to say, weight loss itself has benefits for those who need it in terms of longevity of life and good health. You can also use prolonged fasting to help control the risks of heart disease, type-2 diabetes, some types of cancers and stroke.

By putting your body through ketosis, you can also enjoy the added benefits of burning fat without using up the protein in your body. This makes it easier to grow and maintain muscles during weight training because you are also restricting calorie intake.

Health Benefits Of Prolonged Fasting

When done right, prolonged fasting comes with a range of benefits. Here’s a look at those.

Weight Loss

This is a good way to burn fat and if you continue a healthy regimen after you are done with your prolonged fasting session, you can keep it that way too. So, those who want to lose weight by getting rid of fat can definitely give prolonged fasting a go under, of course, medical supervision.

The switch to a different metabolism that is usually the result of restricting calorie intake is also a good way to lose more than just water weight.

Prolonged Fasting For Weight Loss. measure yourself first ...

Lower Insulin Levels

Prolonged fasting will also reduce your insulin levels, as mentioned earlier, along with glucose levels. Now, you must be careful when you do this and people with medical conditions, especially diabetes should have the support of their Medical practitioner and monitor their insulin levels carefully.

Research has shown that a well-managed prolonged fast can even reduce type 2 diabetes, allowing people to return to a healthy lifestyle.

But if you can benefit from this, you will notice that prolonged fasting can help bring down the risk of cardiovascular problems. Reducing the stress of high metabolic rates will also be good for your blood pressure.

This is how the risk of strokes and inflammation is reduced.


This is a stage in which the body’s metabolism changes because of the fasting exercise and when it goes into ketosis. At this time, your system takes another look at itself and makes changes to start molecular changes that will repair your body.

This has the potential to help you get rid of harmful substances and toxins in the body and remove inflammation. Powerful stuff!

Improved Cognitive Function

You might not expect this one, but this type of fasting has the ability to do some good for your mental health too. That’s because your brain is affected by prolonged fasting too.

Now, this is not a given and it is not for everyone and we will get to that in a minute but when it is applicable, prolonged fasting can help reduce symptoms of mental health problems like depression and anxiety.

This is because when the body is making those above-mentioned molecular changes, it has the opportunity to repair and rejuvenate and remove toxins from the brain.

Possible Side Effects

Now, as you would expect, this is a bit extreme and it does come with a few side effects. The most obvious one might be that you will constantly be hungry in the first couple of days.

And since you are allowed to consume only water, tea and coffee, you will need to have incredible focus to reap the benefits. However, the good news is that after the first 2 – 3 days your body adapts and you no longer suffer from hunger.

Prolonged fasting can also be a risky thing to try if you don’t take care of obvious side effects like fatigue, electrolyte imbalance and dehydration.

You should also expect to have lower levels of energy and be a bit irritable when your body is moving into ketosis. You can, of course, fight it by increasing water intake, resting and taking electrolytes. However, if you are fasting with the help of your Medical Practitioner, they will provide you with advise on how much water to drink and will probably recommend that you add a pinch of quality sea salt to your water and take a quality electrolyte.

And finally, there is the issue of those who have medical conditions doing it without the supervision of their physician. This is not only irresponsible but can prove to be life-threatening. We cannot re-iterate enough that you need an expert to guide you in a prolonged fast.

The Impact Of Prolonged Fasting On Older Adults

When older adults engage in prolonged fasting, studies have shown that they will experience a loss of appetite. If that sounds like a good thing because at a certain age people lose their appetite anyway, you might want to think again.

older couple sitting on a park bench

When it happens naturally, it is often referred to as anorexia of aging. And this is known to have the potential to lead to other problems like:

  • Vision and hearing impairment
  • Gastrointestinal problems
  • Isolation
  • Depression
  • Poly-medication

Studies have also shown that test subjects of prolonged fasting experienced more depression than those who were not fasting for more than 12 hours. Studies have also shown that poor appetite has led test people towards depression when compared to those who have a normal appetite. So, that’s something to be concerned about.

Lack of an appetite has also been linked to low muscle mass, low grip strength and low skeletal muscle mass.

Older adults have also been seen to have trouble getting up from chairs regardless of their usual physical activities when they have tried prolonged fasting for more than 12 hours.

Prolonged Fasting For Weight Loss: Wrapping Up

While the studies have confirmed that some of these aspects need more research, it is important to note that prolonged fasting might not be for everyone. These are facts to be mindful of before diving head first into prolonged fasting.

We recommend a book that will give you a lot more information on both the process of prolonged fasting and short term fasting for older people and the possible benefits:

You can pick up “The Longevity Diet – Slow Aging, Fight Disease, Optimize Weight” by Valter Longo, PHD at Amazon or any good book store. Valter Longo has been studying intermittent fasting, short term fasting and prolonged fasting for many years.

Rosemary Richards