People have practiced fasting for centuries for medical, religious, and ethical reasons. In recent years, intermittent fasting has become increasingly popular worldwide. But this dietary pattern is anything but a fad diet.
Studies show that intermittent fasting can cause various benefits for your overall health. When it comes to your diet, it doesn’t just matter what you eat. It also counts when you eat.
Keep reading to learn about the benefits of intermittent fasting, the risks, and how you can make fasting work.
What Is Intermittent Fasting?
Intermittent fasting is a dietary pattern that focuses on the timing of meals in a day or week.
There are two main types of intermittent fasting:
- Alternate day fasting. This type of fasting alternates 24-hour fasts with 24-hour eating periods. Alternate day fasting often follows the 5:2 strategy, which includes 5 non-restrictive eating days and 2 fasting days in a week. For example, you may fast on Monday and Thursday and eat regularly on all other days. A modified version of alternate-day fasting restricts eating to around 500 calories or no more than 25% of your caloric need on fasting days.
- Time-restricted eating. This type of fasting restricts your eating window to a specific time slot in the day. The most popular form of intermittent fasting is the 16:8 method. This method involves fasting for 16 hours and eating within an 8-hour window. People who follow the 16:8 method typically eat their first meal of the day around lunchtime. For example, you may eat from 11 am to 7 pm. Another popular form of time-restricted eating is the 20:4 method. This dietary pattern involves fasting for 20 hours and eating within 4 hours.
Our bodies react best to intermittent fasting when it aligns with our biological clocks or circadian rhythms. Your circadian rhythm is a 24-hour clock that synchronizes your bodily functions with the rise and fall of the sun. Other cues like eating and sleeping can also influence circadian rhythms.
The gut microbiome has a circadian rhythm that follows standard sleep-wake patterns. For example, digestive functions like gastric emptying increase during the day and decrease at night.
Lifestyle factors such as late-night eating, jet lag, and shift work can disrupt our circadian rhythms and lead to health problems.
8 Benefits of Intermittent Fasting
Intermittent fasting can reset circadian rhythms, resulting in numerous health benefits. Of note, most scientific studies cite these benefits experimented on animals. We’ll outline the benefits of intermittent fasting below.
1. Improves Microbiome Health
Intermittent fasting increases the diversity of the gut microbiome. It also promotes the growth of beneficial bacteria. This results in a greater production of short-chain fatty acids, reducing intestinal inflammation and strengthening the gut barrier.
2. Speeds Up Your Metabolism
Intermittent fasting produces a metabolic change known as ketosis after 6-8 hours of fasting. During ketosis, your body uses stored fat for energy instead of glucose. This results in fat breakdown.
Your liver metabolizes fat into ketones, which are substances that act as an alternative energy source for the cells in your body. Your cells use more energy processing ketones than they do processing glucose. This speeds up your metabolism and can result in weight loss.
3. Induces Autophagy
Intermittent fasting induces autophagy in a wide variety of tissues and organs. Autophagy means “self-eating.” This describes how cells break down old, damaged, or abnormal substances.
Your cells use the energy from these broken-down products for tissue repair and stress resistance. This protects your cells from future damage and environmental stressors.
In the gastrointestinal tract, autophagy prevents leaky gut and can also suppress the growth of colon cancer.
4. Promotes Weight Loss
Intermittent fasting can result in an overall decreased caloric intake if desired. Eating within a shorter time frame makes eating fewer calories than you burn easier. When practiced consistently, intermittent fasting can accelerate weight loss.
5. Lowers Risk of Diabetes
Intermittent fasting can lower the risk of type 2 diabetes by reducing insulin resistance. Fasting decreases insulin levels in the blood and improves the sensitivity of insulin receptors. This allows your cells to use glucose more effectively, which reduces blood sugar levels.
6. Reduces Oxidative Stress and Inflammation
Prolonged nighttime fasting such as the 16:8 method increases antioxidant levels. Antioxidants are substances that can reduce oxidative stress and inflammation. Higher antioxidant levels may improve symptoms of inflammatory bowel disease.
7. Prevents Heart Disease
Fasting can prevent heart disease by improving key risk factors such as hypertension, cholesterol, and diabetes. Intermittent fasting reduces systolic, and diastolic blood pressure, decreases low-density lipoproteins (LDL), increases high-density lipoproteins (HDL), and improves insulin sensitivity.
8. Boosts Brain Health
Intermittent fasting may boost cognitive functioning by altering the composition of the microbiome. The gut influences brain health through multiple pathways known as the microbiome-gut-brain axis.
Remarkably, intermittent fasting may reduce symptoms and disease progression in people with epilepsy, Alzheimer’s disease, and multiple sclerosis.
Risks of Intermittent Fasting
The benefits of intermittent fasting outweigh the risks in the average, healthy individual. However, intermittent fasting isn’t safe for everyone.
Fasting is not recommended for women who are pregnant or breastfeeding. Growing babies and infants need sufficient nutrients for proper development. A shortened eating window can make people more susceptible to missing essential nutrients without careful planning.
Additionally, people who have a history of disordered eating should not try any form of fasting. Any eating pattern that skips meals or restricts food can trigger disordered eating habits.
If approved by their doctors, people with diabetes, kidney disease, and heart disease should only fast under medical supervision.
If you have diabetes and don’t eat for an extended period, your blood sugar levels can become too low. This can lead to hypoglycemia. People with diabetes are also at risk of diabetic ketoacidosis. This life-threatening condition can occur when the liver produces ketones too quickly, which causes them to accumulate in the blood.
Fasting with kidney disease or heart disease can also cause medical problems such as:
- Electrolyte imbalances
- Worsening renal function
- Dehydration
- Fluid overload
How to Prepare for Intermittent Fasting
The following recommendations can help you prepare for intermittent fasting:
- If you have any underlying health conditions, talk to your doctor before trying intermittent fasting. You should ask your doctor if intermittent fasting is safe for you. Your doctor may recommend a modified fasting schedule if you need to take any medication with food.
- Assess your current diet. Are you eating foods that promote a diverse microbiome? Intermittent fasting is most beneficial when combined with a healthy diet. Here, you can learn more about nutrition and lifestyle recommendations that support your gut bacteria.
- Create a meal plan. Meal planning will help ensure you have ingredients on hand to prepare healthy snacks and meals that meet your nutritional needs. It would be best if you opted for foods with a high number of nutrients per calorie. It’s important to know how many calories you need to consume in a day to prevent under eating.
- Mentally prepare for unwanted side effects. It can take up to 2-4 weeks for your body to adjust to an intermittent fasting eating schedule. You may experience headaches, hunger cravings, irritability, and fatigue during this time. Knowing what to expect ahead of time can help you push through these feelings.
Tips for Successful Intermittent Fasting
These tips and tricks can help you succeed with intermittent fasting:
- Enjoy black coffee and tea during your fasting period. Drinking unsweetened, non-caloric beverages won’t break your fast and can help suppress your appetite.
- Drink plenty of water. Water takes up space in your stomach, which helps you feel fuller. Drinking water also keeps you hydrated and can prevent constipation.
- Eat fiber-rich foods. Plant-based foods like fruits, vegetables, and whole grains can help you feel fuller longer. This can reduce hunger pangs during your fasting window. Fiber also promotes a diverse microbiome and regular bowel movements.
- Limit your intake of added sugars. Eating foods with added sugars like candy and soda immediately spikes your blood sugar and increases hunger. You don’t need to cut out junk food entirely, but you should focus on eating whole foods whenever possible
- Avoid eating late at night. Nighttime meals can throw off your circadian rhythm. This can lead to insulin resistance, gastrointestinal problems, poor sleep quality, and more. Try to eat no later than 7 pm to get the most benefit from intermittent fasting.
- Slowly reduce your eating time. Easing into intermittent fasting can reduce unwanted side effects. Starting with an 8-hour eating period with the 16:8 method may help you adapt better than jumping into the 20:4 method.
The Bottom Line
Many studies show the benefits of intermittent fasting. However, most of these studies use animal subjects rather than humans. With the available research, intermittent fasting appears safe in the average, healthy individual. But it’s not safe for everyone. You should always talk to your doctor before trying any significant dietary changes. This is especially important if you have an underlying medical condition.
Intermittent fasting may improve your health by:
- Increasing the diversity of the gut microbiome
- Speeding up your metabolism
- Inducing autophagy
- Promoting weight loss
- Lowering the risk of diabetes
- Reducing oxidative stress and inflammation
- Preventing heart disease
- Boosting cognitive function
There are many forms of intermittent fasting, with fasting periods ranging from 16-hours to 24-hours. You can pick the fasting schedule that works best for you.
It’s unclear which strategy yields the best health benefits. But we do know that intermittent fasting should follow circadian rhythms. This means that you should eat during daylight hours and fast at night. Eating a balanced diet can ensure you get all the nutrients you need within a shortened eating window.
If you want to know if intermittent fasting is right for you, you can call our office at 806-696-4440 or request an appointment online.
