Luke Stanaway

Registered Nutritionist

12 Health Reasons To Give Fasting A Go

12 Health Reasons To Give Fasting A Go

12 Health Reasons To Give Fasting A Go

Key Takeways

  • Intermittent fasting (IF) can help reduce weight, reducing waist circumference by 4-7% and weight by 3-5kg over 10 weeks on average.

  • IF may help maintain muscle mass while dieting.

  • IF alters hormone levels, cellular repair, and gene expression, which benefits the body.

  • IF reduces insulin resistance, lowering blood sugar and the risk of type 2 diabetes.

  • IF reduces oxidative stress and inflammation, which cause chronic diseases.

  • IF may improve heart health by lowering blood sugar, blood pressure, triglycerides, cholesterol, and inflammatory markers.

  • IF induces autophagy, which could protect against cancer and neurodegenerative diseases.

  • IF could potentially improve sleep quality.

  • Before starting intermittent fasting, consult a doctor or nutritionist to see if it's right for you. Results and outcomes may vary.

The Potential Benefits of Intermittent Fasting

Intermittent fasting has grown in popularity as a weight-loss method, but it offers much more. According to animal and human studies, it has the potential to improve your overall health and extend your life. There are several ways to incorporate intermittent fasting into your lifestyle, ranging from daily fasting periods to fasting only on specific days of the week. Individual approaches and outcomes may differ. If you're thinking about starting intermittent fasting, check with your doctor or a nutritionist to see if it's a good fit for you. A discussion of the potential benefits of fasting has been provided below.


1.    Weight-loss

A systematic review of 40 studies found that intermittent fasting can result in significant weight loss, with an average of 3-5kg lost over a 10-week period, equating to 0.4kg lost per week. Some study participants had a 4-7% decrease in waist circumference, indicating a reduction in belly fat. The primary reason for weight loss via intermittent fasting is a reduction in calorie intake. Fasting periods in various protocols involve not eating meals, which results in a reduction in the number of calories consumed unless overcompensation occurs during eating periods.

2.    Maintain muscle mass when dieting

One of the negative effects of dieting is that the body frequently loses both fat and muscle. Interestingly, some research suggests that intermittent fasting may help preserve muscle mass while promoting fat loss. A scientific review discovered that intermittent calorie restriction results in weight loss similar to continuous calorie restriction, but with a much smaller decrease in muscle mass. In the calorie restriction studies, 25% of the weight lost was muscle mass, whereas only 10% was lost in the intermittent calorie restriction studies. However, it is important to note that these studies had limitations, so their findings should be interpreted with caution, and recent studies have failed to find any significant differences in lean mass or muscle mass with intermittent fasting compared to other types of eating plans so the jury is still out on this one.

3.    Hormones, cells, and genes

Many of the benefits of intermittent fasting can be attributed to changes in hormones, cell function, and gene expression. When you fast for a period of time, your body undergoes several changes, including a change in hormone levels that makes stored body fat more accessible and the initiation of critical cellular repair processes. During a fast, your body undergoes the following changes:

  • Insulin levels: Blood insulin levels drop significantly, promoting fat burning.

  • Human growth hormone (HGH) levels: HGH levels in the blood can skyrocket, enhancing fat burning, muscle gain, and a variety of other benefits.

  • Cellular repair: The body initiates critical cellular repair processes such as waste elimination from cells.

  • Gene expression: Positive changes in various genes and molecules have been linked to longevity and disease prevention.

4.    Lowering your risk for type 2 diabetes

Type 2 diabetes, characterised by elevated blood sugar levels in the presence of insulin resistance, has become more common in recent years. Anything that reduces insulin resistance should help lower blood sugar and protect against type 2 diabetes. Intermittent fasting has been shown to have significant benefits for insulin resistance, resulting in a significant decrease in blood sugar levels. In human studies on intermittent fasting, fasting blood sugar was reduced by 3-6% after 8-12 weeks in people with prediabetes, and fasting insulin was reduced by 20-31%. In one study of diabetic mice, intermittent fasting increased survival rates and protected against diabetic retinopathy, a complication that can lead to blindness. This suggests that intermittent fasting may be extremely beneficial for people who are at risk of developing type 2 diabetes. However, there may be some gender differences, as a 2005 study in women found that a 22-day intermittent fasting protocol actually worsened blood sugar management.

5.    Reducing oxidative stress and inflammation

Oxidative stress, caused by unstable molecules known as free radicals, is a factor in ageing and the development of various chronic diseases. These free radicals can cause damage when they interact with other important molecules such as protein and DNA. Several studies have shown that intermittent fasting can help the body resist oxidative stress. Furthermore, studies show that intermittent fasting can help to reduce inflammation, which is another major contributor to many common diseases.

6.    Heart health

Heart disease is the leading cause of death worldwide. It is well understood that various health indicators, known as "risk factors," can increase or decrease the likelihood of developing heart disease. A number of these risk factors have been shown to be reduced by intermittent fasting, including:

  • Blood sugar levels

  • Blood pressure

  • Triglycerides in the blood

  • Levels of total and LDL (bad) cholesterol

  • Inflammatory markers

However, much of this data comes from animal studies. Before any recommendations can be made, more human research is needed to fully understand the impact of fasting on heart health.

7.   Cellular repair processes

During fasting, the body's cells initiate a cellular waste removal process known as autophagy. Within the cells, this process involves breaking down and metabolising accumulated broken and dysfunctional proteins. Increased autophagy has the potential to protect against a variety of diseases, including cancer and neurodegenerative diseases such as Alzheimer's.

8.    Cancer and cell proliferation

Cancer is distinguished by uncontrolled cell proliferation. Intermittent fasting has been shown to have a variety of metabolic benefits that may reduce the risk of developing cancer. Early animal research suggests that fasting or fasting-like diets may help prevent cancer. Similarly, human studies have yielded promising results, though more research is required. Furthermore, there is evidence that fasting can reduce the side effects of chemotherapy in humans.

9.    Brain boosting

Intermittent fasting has been shown to benefit the brain as well as the body. Intermittent fasting has been shown to improve a variety of metabolic features important for brain health. It can help in:

  • Reducing oxidative stress

  • Reducing inflammation

  • Controlling blood sugar levels

  • Improving insulin sensitivity

Intermittent fasting has been shown in rodent studies to stimulate the growth of new nerve cells, which improves brain function. It has also been shown to increase levels of brain-derived neurotrophic factor (BDNF), which plays an important role in the prevention of depression and other brain-related issues. Furthermore, animal studies have shown that fasting can help protect the brain from damage caused by strokes.

10. Alzheimer’s disease and other neurodegenerative diseases

Alzheimer's disease is the most common neurodegenerative disease in the world, and there is currently no cure. As a result, preventing its onset is critical. Intermittent fasting has been shown in animal studies to either delay or alleviate the effects of Alzheimer's disease. A case study discovered that a lifestyle intervention involving daily short-term fasting improved Alzheimer's symptoms in 90% of the participants. Fasting may also protect against other neurodegenerative diseases such as Parkinson's and Huntington's, according to animal studies. However, more human studies are needed to back up these claims.

11. Lifespan extension

The possibility of intermittent fasting extending lifespan is a fascinating discovery. Animal studies, including those on rodents and fruit flies, have shown that intermittent fasting has similar lifespan-enhancing effects to continuous calorie restriction. In a rat study, those who fasted every other day lived 83% longer than non-fasted rats. Another study in mice found that fasting every other day increased lifespan by 13%. Furthermore, daily fasting in male mice improved overall health and delayed the onset of age-related diseases such as fatty liver disease and hepatocellular carcinoma. Although more research is needed to confirm these findings in humans, intermittent fasting is gaining popularity among those looking to delay ageing due to its benefits for metabolism and other health markers. The idea of living a longer and healthier life by fasting intermittently makes sense.

12. Improving sleep quality

Have you ever felt like you couldn't get rid of your drowsiness after a big meal? It's common knowledge that what we eat affects our level of alertness and fatigue. Some Intermittent Fasting practitioners claim that their diet regimen has improved their sleep patterns.

This connection could be explained in two ways. The first is that intermittent fasting aids in the regulation of the circadian rhythm, which governs sleep patterns. Although there is limited research to support this theory, a regulated circadian rhythm may result in easier falling asleep and feeling more refreshed upon waking. This theory was discussed in an article published in the journal "Nature and Science of Sleep" in 2018.

According to the second theory, eating the last meal earlier in the evening allows the food to be fully digested by bedtime. According to the Sleep Foundation, going to bed on an empty stomach, especially if the last meal was heavy or spicy, can interfere with digestion or cause heartburn, making it difficult to fall asleep.


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