Fasting - A Quick How To - Dr. Brian Yeung, ND

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Types of fasting

Fasting is the practice of abstaining from food or drink for a specific period of time. It can be done for a variety of reasons, including religious observance, health, and personal or spiritual growth. There are several types of fasting, including:

Intermittent fasting: This is a pattern of eating that alternates between periods of fasting and periods of eating. The most popular method of intermittent fasting is the 16/8 method, in which individuals fast for 16 hours and eat during an 8-hour window. Another common form is the 5:2 diet, in which individuals eat normally for five days and restrict their calorie intake to 500-600 calories on two non-consecutive days.
Juice fasting: This type of fasting involves consuming only fresh fruit and vegetable juices for a specified period of time, typically ranging from 1 to 7 days. Juice fasting is often used for detoxification and weight loss purposes.
Water fasting: This type of fasting involves abstaining from all food and drink, except for water, for a specified period of time. It is typically carried out for short periods of time, ranging from 24 to 72 hours, and is often used for weight loss or detoxification purposes.
Complete fasting: This type of fasting involves abstaining from all food and drink for a specified period of time, usually ranging from 12 to 72 hours. Complete fasting is often used for spiritual or religious purposes, and is typically carried out under the supervision of a spiritual leader or healthcare professional.

Religious fasting

Religious fasting is an important type of fasting that is practiced by many different religious communities. Some examples include:

Lenten fasting in Christianity: During the 40-day period leading up to Easter, many Christians observe a period of fasting and self-reflection. The specific requirements for Lenten fasting can vary among Christian denominations, but it often involves reducing or eliminating certain foods from the diet.
Ramadan fasting in Islam: During the Islamic month of Ramadan, Muslims abstain from food and drink from sunrise to sunset. After sunset, they break their fast with a meal called iftar.
Yom Kippur fasting in Judaism: Yom Kippur is the Jewish Day of Atonement, and it is observed by fasting for 25 hours. During this time, Jews abstain from food and drink, and focus on prayer and reflection.
Fasting in Hinduism: Hinduism also has several fasting traditions, including the Ekadasi fast, which is observed twice a month, and the Navaratri fast, which is observed for 9 days during the Hindu festival of Navaratri.

Health benefits

Fasting has been shown to have several potential health benefits, including:

Weight loss: Fasting can lead to weight loss by reducing calorie intake and promoting the use of stored fat for energy.
Improved metabolism: Fasting has been shown to improve insulin sensitivity, which can help regulate blood sugar levels and reduce the risk of type 2 diabetes.
Reduced inflammation: Fasting has been shown to reduce levels of inflammation in the body, which has been linked to a range of chronic diseases, including heart disease, cancer, and Alzheimer’s disease.
Improved heart health: Fasting has been shown to lower blood pressure and cholesterol levels, which can reduce the risk of heart disease.
Increased longevity: Studies have shown that fasting can extend lifespan in animals and may have similar benefits for humans.
Increased mental clarity and focus: Fasting has been shown to improve mental clarity and focus, likely due to the increased production of neurotransmitters, such as norepinephrine and dopamine.
Improved cellular repair and renewal: Fasting has been shown to promote cellular repair and renewal processes, including autophagy, which is the body’s natural process for cleaning out damaged cells and replacing them with new, healthy ones.

Weight loss

Fasting is a popular weight loss strategy that involves restricting calorie intake for a certain period of time. While fasting can be an effective weight loss tool, it’s important to do it safely and in a way that promotes overall health. Here are some tips for fasting for weight loss:

Start slowly: If you’re new to fasting, start with a shorter fasting window and gradually increase it over time. This can help your body adjust to the changes and reduce the risk of negative side effects.
Stay hydrated: It’s important to stay hydrated during a fast, so be sure to drink plenty of water, herbal tea, or other non-caloric beverages.
Avoid bingeing: When breaking a fast, it’s important to avoid bingeing on high-calorie foods. Instead, opt for nutrient-dense foods that are easy to digest, such as soups, smoothies, or salads.
Monitor your health: If you have any underlying health conditions or are taking medication, it’s important to talk to your healthcare provider before starting a fast. They can help you determine if fasting is safe for you and provide guidance on how to do it safely.

Extreme fasting, or fasting for prolonged periods of time, such as several days or weeks, can be dangerous and may lead to malnutrition, dehydration, and other health complications. Furthermore, the weight lost during these fasts are temporary, and are quickly regained once your diet returns to normal.

Improved metabolism

Fasting has been shown to have various effects on metabolism, which is the process by which our bodies convert food into energy. Here are some ways that fasting can potentially improve metabolism:

Increases insulin sensitivity: Insulin is a hormone that regulates blood sugar levels and plays a key role in metabolism. Fasting has been shown to increase insulin sensitivity, which means that the body is better able to use insulin to regulate blood sugar levels. This can lead to improved metabolism and lower risk of conditions like diabetes and metabolic syndrome.
Boosts fat burning: Fasting can increase the body’s ability to burn fat for energy, which can improve metabolism and aid in weight loss. During fasting, the body switches from using glucose (sugar) for energy to using fat stores, which can lead to a reduction in body fat and improved metabolic health.
Increases growth hormone: Fasting has been shown to increase levels of growth hormone, which can help to build and maintain muscle mass. Muscle tissue is metabolically active, meaning that it burns more calories at rest than fat tissue. By increasing muscle mass, fasting can potentially improve metabolism and increase calorie burning.
Reduces inflammation: Chronic inflammation is linked to many health problems, including insulin resistance and metabolic syndrome. Fasting has been shown to reduce inflammation in the body, which can improve metabolism and reduce the risk of these conditions.

Health risks

Fasting, especially for longer periods of time, may not be appropriate for everyone, and there are certain groups of people who should avoid fasting altogether or do it under medical supervision. Here are some examples:

Pregnant or breastfeeding women: Fasting during pregnancy or while breastfeeding can be harmful to both the mother and the baby. It’s important to consume enough nutrients and calories to support a healthy pregnancy and to provide adequate nutrition for the baby.
Children and teenagers: Fasting may interfere with normal growth and development in children and teenagers, and it’s not recommended for this age group.
People with certain medical conditions: Fasting may not be appropriate for people with certain medical conditions, such as diabetes, hypoglycemia, liver or kidney disease, or eating disorders. People with these conditions should consult with their healthcare provider before starting a fast.
People taking certain medications: Some medications may require regular food intake, and fasting may interfere with the absorption or effectiveness of these medications. People taking medications should consult with their healthcare provider before starting a fast.
People who are underweight: Fasting may cause further weight loss in people who are already underweight, which can be harmful to their health. It’s important to maintain a healthy weight and consume enough nutrients to support overall health.

Overall, it’s important to talk to your healthcare provider before starting a fast to determine if it’s safe and appropriate for your individual health status and needs.

In diabetics

People with type 2 diabetes have high levels of glucose in their blood, which can lead to a range of health problems if not managed properly. While fasting may not be appropriate for everyone with type 2 diabetes, it can be done safely and can potentially improve the condition in some cases:

Improves insulin sensitivity: Fasting has been shown to improve insulin sensitivity in people with type 2 diabetes. By reducing insulin resistance, the body is better able to use insulin to regulate blood sugar levels, which can lead to improved glucose control.
Reduces blood sugar levels: Fasting can lead to a reduction in blood sugar levels, which can be beneficial for people with type 2 diabetes. By limiting the intake of carbohydrates, the body produces less glucose and relies on stored glucose (glycogen) and fat for energy.
Promotes weight loss: Fasting can lead to weight loss, which is an important factor in managing type 2 diabetes. Excess body fat can contribute to insulin resistance, and losing weight can help to improve insulin sensitivity and glucose control.

However, people with type 2 diabetes should be cautious when fasting and should talk to their healthcare provider before starting a fasting regimen.

Some potential risks of fasting for people with type 2 diabetes include hypoglycemia (low blood sugar), hyperglycemia (high blood sugar), and dehydration. It’s important to monitor blood sugar levels closely and to follow a safe and appropriate fasting plan.

How to fast for health

What can I have during a fast?

The exact types of foods allowed can vary. However, when fasting for health or medical reasons, a general fast includes the following rules:

YES water with some lemon or lime, coffee, and tea (NO milk, cream or sugar)
SOME 0 calorie sweeteners (allulose, erythritol, inulin, stevia, sucralose)
SOME 0 calorie pop or soda (not too much)
SOME close to 0 calorie broths (not too much)
NO caloric juices of any type, smoothies, milk
NO solid foods or snacks of any type
NO foodstuffs with any significant calories

Supplements

During fasting, the body won’t have any nutrients due to reduced food intake. As a result, some people may choose to take supplements to support their overall health during this time without breaking their fast. Here are some supplements that may be helpful during fasting:

Multivitamins: Taking a multivitamin can help ensure that the body is getting the necessary vitamins and minerals during fasting, especially if the diet is restricted or limited.
Electrolytes: Fasting can lead to electrolyte imbalances, which can cause symptoms like headaches, fatigue, and muscle cramps. Taking electrolyte supplements or drinking electrolyte-rich fluids like coconut water can help prevent these symptoms, especially if you are still physically active while fasting.
Probiotics: Fasting can affect the gut microbiome, which can impact overall health. Taking probiotics during fasting may help maintain a healthy gut microbiome.
Omega-3 fatty acids: Omega-3 fatty acids have anti-inflammatory properties and can help support overall health during fasting. They can be taken as supplements or liquid form.

Tips and recommendations

Start with a shorter fast. If you are new to fasting, start with a shorter fast such as a 12-hour or 16-hour fast. Once you are comfortable with shorter fasts, gradually increase the duration of your fast.
Remain well hydrated. Fasting increases your risk of becoming dehydrated. Consume at least 6-10 glasses of liquid (at least 1.5 L liquid) throughout the day.
Minimize caffeine and alcohol. Caffeine and alcohol, even if they contain minimal calories, can dehydrate your body and make you feel more hungry. It’s best to avoid them during a fast.
Minimize artificial sweeteners. Artificially sweetened pop like coke zero may have no calories, but the excessive sweetness can trigger cravings and make it more difficult to complete your fast.
Reduce stress. The fasting period can be a stressful time for your body. Try to reduce the amount of strenuous activities such as exercise, work, or playing sports temporarily. Make sure you get good sleep every night. It is also strongly encouraged that you engage in stress reducing activities such as yoga or meditation.
Keep busy. Keeping yourself busy can help distract you from hunger and keep your mind occupied. Consider engaging in activities such as reading, exercising, or spending time with friends and family.
Get plenty of rest. Resting and getting adequate sleep is important during a fast. It can help reduce stress and keep your body in a state of relaxation.
Persevere, you can do it! Remember, the degree of success depends on your level of commitment.

Managing symptoms

Sometimes, fasting can cause temporary symptoms that can be uncomfortable. Here are some common adverse effects and how to manage them:

Cravings. Avoid being near food. Your body will physiologically react to the sight and smell of food, and this may cause heartburn or make it hard to continue to fast. Try to avoid being near food or others when they are cooking or consuming food.
Dizziness. If you experience dizziness, light-headedness, or disorientation, your blood sugar levels may be low. Consume a sweet juice or sugary drink, or place sugar or a sugar-rich sweet below your tongue right away.
Heart palpitations. If you experience heart palpitations or fluttering, you may have an electrolyte imbalance. Consume an electrolyte-rich drink such as coconut water, or a freshly blended juice that contains spinach, collard greens, oranges, bananas or apples.
Heartburn. If you experience heartburn, try to avoid seeing or smelling food nearby. Otherwise, sipping a blended high-fibre smoothie can help alleviate symptoms. If you are on heartburn/GERD medication, you need to continue it even when you are not eating any solid food.
Headaches. If you experience headaches, try to slowly wean yourself off certain foods/drinks such as coffee. Abruptly stopping coffee can lead to caffeine-withdrawal headaches. Maintaining adequate hydration is also important in reducing withdrawal symptoms. If headaches persist, taking some acetaminophen (Tylenol) can help quickly alleviate it.
Constipation or diarrhea. If you experience constipation or diarrhea, you can try taking a soluble fiber supplement like psyllium husk or inulin fiber, or if your fast allows, consume more blended high-fibre smoothies to keep yourself regular.

Fasting – A Quick How To