Does Intermittent Fasting Slow Your Metabolism?

Key takeaways

• Intermittent fasting is a technique where you only eat for certain periods each day and don’t eat outside of those windows.
• Metabolic health plays a crucial part in maintaining healthy energy levels and promoting weight loss.
• Intermittent fasting impacts your metabolism by speeding up function in the short term and improving insulin sensitivity in the long term.
• Incorporating intermittent fasting in conjunction with holistic weight loss efforts can promote metabolic health and help you shed pounds.

Intermittent fasting is a technique in which you eat only during certain periods of time each day and not outside of that window. During a fasting window, you avoid eating entirely and only drink water or zero-calorie beverages like coffee or tea.

There are several different approaches to fasting, like fasting for two days of the week and eating normally for the other five or fasting for an eight to 16-hour window each day. When done right, intermittent fasting has a variety of potential health benefits, like reducing inflammation and boosting memory.

However, many people looking to lose weight consider intermittent fasting as a potential option—begging the question of how intermittent fasting affects the metabolism. With the important role that metabolism plays in weight loss, this is an important question for anyone looking to lose weight. Research shows that intermittent fasting may actually have some positive effects on metabolic health and weight loss, but that doesn’t mean it’s the full solution.

What Is Metabolism?

Metabolism is the process by which the body converts the foods we eat into energy. Metabolic health plays an integral part in giving us the energy to handle our day-to-day activities. The metabolism’s function can vary depending on the person. Your body uses energy in the form of calories to engage in physical activity, as well as maintain your natural body functions at rest—this is known as your basal metabolic rate.

Everyone’s metabolism is different, so for some people, it may work faster or slower. The speed of your metabolism is largely determined by genetics, but your metabolic health and function may also be impacted by other key factors like your stress levels and lifestyle choices.

The metabolism plays a key role in weight loss. At a basic level, weight loss happens when you use more calories for maintaining activity than you consume through food. By understanding how your metabolism functions and taking steps to improve your metabolic health, you can put yourself in the best possible position for sustainable weight loss.

How Intermittent Fasting Affects Metabolism

Research has found that intermittent fasting offers several potential benefits for your health, like improving memory, promoting heart health, and boosting physical performance. These benefits have led researchers to study intermittent fasting’s impact on metabolic health as well, and there are a few promising results.

Fasting facilitates a process called “metabolic switching,” which encourages weight loss—when in a fasting state, the body will begin using fat stores for energy instead of the calories you eat through food. This effect will lead to the burning of fat and losing weight.

Some research suggests that fasting for short periods may boost your metabolism while fasting for longer periods can actually slow it down. Any form of weight loss can slow the metabolism by reducing muscle mass, but it appears that fasting can still offer benefits both in the short and long term. 

In the short term, benefits include:

• Fasting can increase your metabolism by as much as 14%, according to one study.
• Fasting increases the levels of fat-burning hormones in the blood, like norepinephrine and human growth hormone.

Meanwhile, in the long term, benefits include:

• Weight loss often leads to a loss of muscle mass, which can slow the metabolism. Intermittent fasting better preserves muscle mass compared to consistent calorie reduction.
• Intermittent fasting can improve insulin sensitivity, making your body more efficient at processing sugar and using it for energy.

However, it’s important to note that according to a significant amount of research, many of the benefits of intermittent fasting seem to be the result of the reduced calorie intake rather than the fasting process itself.

Individual Variability

As with any approach to weight loss, you can’t expect intermittent fasting to have the same effects for you as it does for anyone else. There is no one-size-fits-all approach, so what works for you may not work for everyone.

Any of the following factors can impact your metabolic health:

• Gender
• Age
• Genetics
• Stress levels
• Overall health

If you begin intermittent fasting, it’s important to start with realistic expectations. Just because your friend at the office started intermittent fasting and immediately shed pounds doesn’t mean that you will, too. Still, as long as you integrate intermittent fasting with a healthy approach surrounded by a blend of effective weight loss strategies, you may see some results with the right amount of patience.

Implementing Intermittent Fasting Safely

Intermittent fasting can offer some potential benefits, but you shouldn’t overlook that it’s a big lifestyle change. When you first start, you may experience side effects like hunger, fatigue, headaches, and more. If you’re not careful, intermittent fasting can be harmful, particularly if you’re not eating enough to give your body the fuel it needs.

To fast safely, keep the following tips in mind:

• Introduce fasting gradually – Fasting is a significant change to your diet. It’s important to introduce it into your diet gradually so you can give your body time to adjust.
• Choose an approach that fits your lifestyle – There are multiple approaches to fasting with different windows throughout the day and week. Choose one that best fits best within your work and activity schedule.
• Listen to your body – If you feel overly fatigued or unwell after intermittent fasting, then you should stop or seek support from a medical professional or nutritionist.

Always be sure to consult your doctor to see if intermittent fasting is safe for you, especially as some groups must be extra cautious. For example, women who are pregnant or breastfeeding, people who have a history of eating disorders, and people with type 1 diabetes who rely on insulin should all use caution and consult a healthcare provider before fasting.

Improve Your Metabolism Holistically

Intermittent fasting may have some short-term benefits for your metabolism when you find a healthy way to incorporate it, but the long-term benefits are unclear. Ultimately, fasting is not the guaranteed solution to weight loss—the best path to weight loss is a holistic approach that includes incorporating lasting habits and lifestyle adjustments.

At re:vitalize weight loss & wellness, we’ll work with you to take the necessary steps to promote metabolic repair like performing a personalized metabolic age assessment, creating a personalized micro-nutrient supplement protocol, and providing a customized food list that highlights the optimal nutrients for your health. 

Metabolic repair is just one facet of our holistic Weight Loss & Metabolic Reset programs—we’ll also help you build healthy habits that promote improved energy, better sleep, and more, all on the path to sustainable weight loss.Contact us today to schedule a 1:1 consultation with our team, learn more about your body composition, and get the support you need to achieve your weight loss goals.