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Steve Berry > Blog  > Intermittent Fasting
Intermittent Fasting

Intermittent Fasting

Intermittent fasting involves eating during a specific time period, followed by a period of fasting where no food or drink is consumed. According to scientific research, intermittent fasting has many physiological and mental benefits that will be discussed in this article.


Digestive System & Energy Levels: When we eat, the digestive system has to use energy in order to breakdown food into small particles in order for the body to absorb the nutrients. Eating frequently or eating large meals will use up a lot of energy, which can make you feel lethargic. This may also increase gut inflammation and cell proliferation. Fasting reduces this, and gives the digestive system time to rest, which will boost energy levels.

Heart & Blood Cells: People often think of their stomach when it comes to eating but your heart also plays a part. Eating heavy meals increases the risk of heart attack. Eating unhealthy foods increases the risk of heart disease. When you eat, your heart rate increases to provide the digestive system with more energy to break down the food. The insulin in your blood also increases, causing blood sugar (glucose) to rise. Intermittent fasting reduces resting heart rate, blood pressure, insulin and leptin, a hormone that’s linked to body fat and obesity.

Fat Burn: As mentioned above, fasting reduces leptin production, which decreases hunger and fat storage. Fasting also increases adiponectin, a hormone that regulates glucose levels and breaks down fatty acid. It also increases lipolysis, which also breaks down fats. Want to melt fat? Try intermittent fasting.

Brain Health: fasting is also proven to boost cognitive function, increase stress resistance, reduce the risk of stroke, reduce depression, reduce dementia and generally helps keep our brains staying younger.


Ways to Fast:

16:8 Fast (good for getting lean): eat within an 8 hour period every day (typically 12pm-8pm), fasting for the other 16 hours. Eat high protein and low refined carbs during the cycle. Aim to eat the largest meal post workout. You can still drink water, herbal tea, black coffee and most calorie free drinks during the 16 hour fast.

5:2 Fast eat normally for 5 days in a week and on the remaining 2 days, fast or reduce calorie intake to around 500 or less over the 2 days.

Start-Stop Fast eat on 1 day normally. On the next day fast. Repeat.

Warrior Fast: fast during the day for 20 hours. Eat a large, high calorie meal at night. Typically, you would do a 3 week cycle to adapt to this method, however this method is difficult to adapt to and sustain long term, hence the name.


Negative Effects of Fasting:

Diabetics: Fasting may increase ketones, which are chemicals that are produced in the liver when your body cannot produce enough insulin to turn sugar (glucose) into energy. Your body needs to find another source, so your body turns fat into ketones which is sent to the blood stream. Normally, this process is not a problem for someone without diabetes, however, too many ketones in a diabetic person can be fatal. Therefore, fasting is not recommended for people with diabetes because it can lead to dangerous spikes and dips in blood sugar levels.

Nutrients: Fasting for long periods of time can be bad for you, especially if you exercise regularly or have a physical job. Your body needs carbohydrates for energy, as well as other nutrients like vitamins and minerals.

Underweight: fasting isn’t recommended for someone who is underweight because it will cause more harm than good. High calorie diets are recommended for people who are underweight to ensure that their body is getting enough nutrition and energy.


Intermittent fasting may cause hunger, fatigue (physical and mental) and cravings so it might not be right for everyone. I would recommend it to people who are overweight and sedentary. People who are highly active, underweight or diabetic should avoid it. Always seek advice from a doctor before starting a diet.