Intermittent Fasting can help?
In my previous article, Why Am I Strong but Still Have Belly Fat?, I explained how a routine blood test completely changed the way I looked at nutrition, weight loss and long-term health. One of the biggest lifestyle changes I made afterwards was adopting intermittent fasting. It became the foundation of my daily routine and, over the following eight months, helped me lose around ten kilograms without constantly feeling hungry. But my personal experience also raised an important question: why does intermittent fasting work so well for some people while others struggle to see any meaningful results?
Intermittent fasting has become one of the most discussed nutrition strategies of the past decade. Supporters describe it as a simple and sustainable way to lose weight, improve blood sugar control and even promote healthy ageing. Critics argue that it is simply another diet with a fashionable name. As is often the case, the scientific evidence lies somewhere between those two extremes.
Unlike many traditional diets, intermittent fasting does not tell you exactly what to eat. Instead, it focuses primarily on when you eat. The most popular approach is the 16:8 method, where food is consumed during an eight-hour eating window followed by approximately sixteen hours without calories. Other approaches include the 5:2 method or occasional 24-hour fasts, but the underlying principle remains the same: giving the body extended periods without food.
Fasting Is Nothing New
Although intermittent fasting has become enormously popular on social media, the concept itself is anything but new. Throughout human history, periods without food were entirely normal. Our ancestors did not have refrigerators, supermarkets or food delivery services. Eating depended on hunting, gathering and seasonal availability. The human body therefore evolved with the ability to function during both feeding and fasting periods.
Many religions have also included fasting for centuries. Whether during Ramadan, Lent or other religious traditions, temporary fasting has long been associated with discipline, reflection and self-control. Modern intermittent fasting differs in its purpose, but it demonstrates that the human body is well adapted to temporary periods without food.
What Happens During the First Hours of Fasting?
Immediately after eating, the body enters what scientists call the fed state. Blood glucose rises, insulin is released and nutrients are directed towards muscle tissue, the liver and fat stores. During this period the body primarily burns glucose obtained from the recent meal.
Several hours later, as digestion is completed, insulin levels gradually begin to fall. The liver starts releasing glucose from its glycogen stores in order to maintain a stable blood sugar level. Glycogen acts as the body's short-term carbohydrate reserve and provides energy between meals.
As the fasting period continues, glycogen stores slowly decline. The body increasingly relies on stored fat to meet part of its energy needs. This metabolic shift does not happen at exactly the same time in every individual because meal composition, physical activity, liver glycogen stores and overall metabolic health all influence the process. Nevertheless, lowering insulin for longer periods allows fat stored in adipose tissue to become more readily available as a fuel source.
Why Lower Insulin Levels Matter
One of the most important effects of intermittent fasting is not that it somehow "switches on" fat burning, but that it reduces the amount of time during which insulin remains elevated. Insulin is an essential hormone that allows glucose to enter cells, but when we constantly snack throughout the day, insulin may remain elevated for much longer than necessary.
Lower insulin levels during fasting make it easier for the body to access stored fat as an energy source. This does not override the laws of energy balance—weight loss still depends on consuming fewer calories than the body uses over time—but it may make maintaining that calorie deficit considerably easier for many individuals. Feeling less hungry between meals was certainly one of the biggest benefits I experienced personally.
Lower insulin exposure may also improve insulin sensitivity over time, particularly when intermittent fasting is combined with weight loss, regular physical activity and an overall healthy diet. Readers who would like to understand this process in greater depth can find a detailed explanation in our companion article, Insulin Resistance Explained: Causes, Symptoms, Prevention and Treatment.
Intermittent Fasting Is Not About Starving Yourself
One of the biggest misconceptions surrounding intermittent fasting is the belief that success comes simply from skipping meals. In reality, fasting is not intended to encourage chronic undernutrition or extreme calorie restriction. The goal is to create structured eating patterns that are easier to maintain while still providing the body with sufficient protein, healthy fats, fibre, vitamins and minerals.
Someone who spends eight hours eating highly processed foods far beyond their calorie requirements is unlikely to experience meaningful improvements in body composition. Likewise, someone who fasts for sixteen hours but neglects strength training and overall nutrition should not expect dramatic changes. Intermittent fasting is best viewed as a tool that supports healthy habits rather than replacing them.
Does Intermittent Fasting Burn More Fat?
One of the most common claims surrounding intermittent fasting is that it somehow forces the body to burn dramatically more fat than conventional diets. The scientific picture is more nuanced. Fat loss still depends primarily on maintaining an energy deficit over time. Intermittent fasting does not change the fundamental laws of metabolism. What it often changes is how easy it becomes to achieve that calorie deficit without constantly feeling hungry.
Many people naturally eat fewer calories simply because they have fewer opportunities to eat during the day. Others find that structured eating windows reduce mindless snacking, particularly during the evening when high-calorie foods are often consumed out of habit rather than hunger. This was certainly one of the biggest advantages I experienced myself.
What About Autophagy?
Autophagy is frequently presented on social media as the ultimate reason to practice intermittent fasting. In reality, the science is considerably more complex. Autophagy is the body's natural process of breaking down and recycling damaged cellular components. It plays an essential role in maintaining healthy cells throughout life.
Animal studies have shown that fasting can stimulate autophagy, but determining exactly when meaningful levels occur in humans remains difficult. Factors such as fasting duration, physical activity, age and overall health all influence the process. While autophagy represents an exciting area of research, it should not be viewed as the primary reason to adopt intermittent fasting. Weight management, improved dietary structure and better metabolic health remain the strongest evidence-based benefits.
Will You Lose Muscle?
A common concern is that going many hours without food automatically causes muscle loss. Fortunately, this fear is often exaggerated. During a typical 16:8 fasting schedule, healthy adults who consume sufficient protein and continue resistance training generally maintain their muscle mass remarkably well while losing body fat.
Muscle preservation depends far more on total daily protein intake, progressive strength training and overall calorie balance than on eating every two or three hours. In fact, maintaining muscle mass is one of the reasons why resistance training should remain part of every weight-loss programme, regardless of whether someone practices intermittent fasting or follows a more traditional eating schedule.
Who Should Avoid Intermittent Fasting?
Intermittent fasting is not appropriate for everyone. Pregnant or breastfeeding women, children, individuals with a history of eating disorders and people taking medication that affects blood glucose should always seek medical advice before making significant dietary changes. Individuals with diabetes, particularly those using insulin or glucose-lowering medication, should never begin fasting without guidance from their healthcare provider because fasting may increase the risk of hypoglycaemia.
Even among healthy adults, intermittent fasting should never become an excuse for obsessive eating habits or extreme calorie restriction. Any nutritional strategy that creates unnecessary stress or cannot be maintained over the long term is unlikely to provide lasting benefits.
Consistency Always Beats Perfection
Looking back, I don't believe intermittent fasting worked because it was a miracle diet. It worked because it gave me a routine that suited my daily life. I stopped constantly thinking about food, reduced unnecessary snacking and found it much easier to control my appetite. Combined with strength training, regular walking and paying closer attention to my blood sugar, those habits gradually became part of my lifestyle rather than a temporary project.
Perhaps the biggest lesson was that successful weight management rarely depends on finding the perfect diet. It depends on finding habits that remain realistic not for a few weeks but for many years.
The Bottom Line
Intermittent fasting is neither a miracle cure nor another passing fad. It is simply one nutritional strategy that can help many people reduce calorie intake, improve meal structure and support better metabolic health. For some individuals it will feel natural and sustainable. Others may achieve the same results using completely different approaches.
The most important lesson from both scientific research and my own experience is that lasting success comes from consistency. Healthy food choices, adequate protein, regular physical activity, sufficient sleep and sustainable daily routines will always have a greater impact than chasing the latest nutrition trend. Intermittent fasting can be an effective tool—but only when it becomes part of a balanced lifestyle rather than a short-term solution.
Sources:
National Institute on Aging – Intermittent Fasting: What We Know About the Science
Harvard T.H. Chan School of Public Health – Intermittent Fasting
Johns Hopkins Medicine – Intermittent Fasting: What Is It and How Does It Work?
