If you think intermittent fasting could be a good fit for you, that’s great because it has tremendous potential to help you lose fat.
A review article conducted in 2020 looked at 27 trials where participants took part in some form of Fasting. They found that fasting resulted in weight loss between 0.8-13.0% from baseline body weight and waist circumference decreased (in the studies that recorded it). This systematic review of 40 studies found that intermittent fasting participants typically lost 7-11 pounds over 10 weeks.
Several experts and policymakers have developed the American Dietary Guidelines 2020-2025. Essentially, they are a set of dietary recommendations updated every 5 years. When we summarize the high-quality evidence available to us in these guidelines (as well as in consensus statements and high-quality studies), we can see that a healthy diet (or healthy dietary patterns) is made up of the following components:
- Eat plenty of whole fruits and vegetables of all types
- Eat high-fibre starches and choose mainly whole grains.
- Eat protein-containing foods from various sources.
- Choose minimally processed fats and oils from plant sources.
When you eat a ‘normal’ meal, glucose (from carbs) and fatty acid (from fats) are the primary energy sources for your cells. After you’ve eaten, glucose is used as a direct energy source, and fatty acids are stored in your fat tissue as triglycerides.
When you fast, meaning you are eating nothing or very little, your body runs out of glucose and needs an alternative energy source to keep going. It now breaks down your triglycerides into their components (fatty acids and glycerol), and your liver will convert them into ketone bodies.
Ketone bodies (or ketones for short) can be used as an alternative energy source for many tissues, including the brain. When you eat enough food (from all 3 macronutrient groups- carbohydrates, proteins, and fats), the number of ketones in your blood is low. When you fast, this level rises within the first 8-12 hours, reaching between 0.2-0.5 millimolar (mM) levels, maintained for about 24 hours with a subsequent increase to 1-2 mM by around 48 hours. However, fuel is not the ketone’s only function; it also significantly affects your cells and organs. For example, ketones able to:
Improve mitochondrial function
Mitochondria are often referred to as the powerhouses of our cells. Energy in our body is mainly from mitochondria releasing energy from ATP molecules. When we suffer from metabolic disturbances and obesity, our mitochondrial function is reduced, but Fasting may help improve this function.
Help your cells become more resistant to stress
During these times of food restriction, the cells adopt a stress resistance mode. Essentially you are making your cells more challenging to withstand.
Autophagy, Latin for “self-eating,” refers to when cells purposely eat other cells in your body. They might sound like a bad thing, but it’s not. Autophagy allows your cells to clean up “cellular garbage” that usually accumulates in cells or when you are hurt or sick. It’s your cell’s version of taking out the trash! When autophagy doesn’t work properly, your immune system attacks this cellular garbage and can cause low-grade, chronic inflammation (the basis of most chronic diseases).
When you eat or break the fast, the body is forced to switch from Fasting and using ketones to glucose. This is known as ‘metabolic switching.