Intermittent Fasting

By: Kelly Gilthorpe Burkenstock, M.D.


Religions have long maintained that fasting is good for the soul, but its health benefits were not widely recognized until the doctors began using various fasting diets to treat many issues – such as diabetes, obesity and epilepsy. Interestingly, fasting as a treatment for epilepsy dates back to the Roman Era where people with epilepsy were caged and not fed to rid them of their demons.

Whether you practice fasting for spiritual, health or medical reasons, most people will fast at some point in life.

Intermittent fasting is a regimen that cycles between periods of fasting, with either no food or significant calorie reduction, followed by periods of unrestricted eating. It changes body composition through loss of fat and weight, while also improving many health parameters associated with disease such as – blood pressure, cholesterol, inflammation, obesity, brain health, heart health, Aging, andropause and menopause, and cancer. Intermittent fasting drains the body of your glucose (sugar) reserves – the main energy source from the foods we eat. Without this glucose reserve, your body switches to burning fat as fuel – known as ketosis. There are many different versions of intermittent fasting, some notable examples include:

5:2 Fast, consisting of eating normally for 5 days every week and fasting for 2 days. On the 2 fasting days the client restricts their calorie intake to 500-600 calories per day. The other 5 days the client eats normally and unrestricted.

16:8 Fast, clients eat normally and unrestricted for 8 hours and fast for the remaining 16 hours- drinking only water and calorie free drinks.

18:6 Fast, clients eat normally and unrestricted for 6 hours and fast for the remaining 18 hours- drinking only water and calorie free drinks.

2:5 Juice Cleanse Fast, a quality juice cleanse is used for 48-72 hours, (2-3 days),and then clients eats nutritious meals after the cleanse is complete. A low sugar, low salt, all natural product, enriched with vitamin, mineral and fiber can be an excellent weight loss plateau breaker. Clients eat normally and unrestricted 5 days, and fast with a quality juice cleanse for 2 days.

When you switch to an intermittent fasting diet plan, you upgrade your body’s performance in a number of ways. Your body initiates a number of important hormonal changes which make fat more accessible to burn. There are diverse and powerful benefits thought to occur due to intermittent fasting: weight loss, disease prevention, improved memory, brain restoration, heart health, better mood, decrease in insulin resistance, increase in lifespan (Anti-Aging); enhancement in stress tolerance and an upgrade to the immune system. Several trials have shown significant weight loss, without an overall increase in appetite. Though these benefits are proven in animal trials, we await final confirmation from ongoing human trials.

Part 1
Weight Loss

By eating fewer meals, intermittent fasting can lead to an automatic reduction in calorie intake. Additionally, intermittent fasting changes hormone levels to facilitate weight loss. Hormones increase the release of the fat burning hormone norepinephrine, (also known as noradrenaline). By helping you eat fewer calories and burn more calorie fuel, intermittent fasting causes weight loss by ramping up the fat burn and decreasing the calorie intake. Intermittent fasting can be a powerful weight loss tool.

A 2014 review showed this eating pattern can cause a 3 to 6% weight loss over a 6 month span. Also noted, people lost 4 to 7% of their waist circumference – a significant amount of dangerous belly fat. Lethal belly fat surrounds the abdominal organs and contributes to heart disease. Intermittent Fasting also causes less muscle mass loss than traditional diets with daily continuous calorie restriction, a welcomed plus!

Foolproof? Unfortunately not, the main reason for success with intermittent fasting is that you eat less calories overall, so if you binge on massive amounts of food, or indulge in high fat, junk carbs, and/or processed foods; or consistently eat against your personal DNA macronutrient profile you may not lose any weight at all.

I recommend incorporating a juice cleanse detox into your life, with a quality grade juices cleanse product plus raw greens or one salad per day for several days. This acts as a method of intermittent fasting, to slow aging and prolong lifespan as an easier alternative to water fasting. Water fasting has a rapidly decreasing effect at removing toxins, as nutrients necessary for the removal also decrease as the water fast progresses. Also, a juice cleanse fasting enables clients to continue to work and is safer than water fasting. Juice cleanse fasting prevents dehydration, loss of electrolytes and fainting.

A few days of juice cleansing can be a great way to reset your taste buds and jumpstart a new, healthful diet. However, there is no health benefit of trying to use a juice cleanse as temporary detox, just to return to a bad diet. This intermittent fasting magic only works if you stick with a nutritious diet longterm, incorporating some juice cleansing and occasional caloric restriction.

As always please consult a physician before starting any diet plan if you have any medical condition, especially if you are a diabetic, pregnant or nursing.

Stay tuned to part 2 Intermittent Fasting and Brain Health.
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– Dr. Kelly Gilthorpe Burkenstock is an internal medicine physician and has studied abroad with several of the world’s foremost international luminaries. She has locations in Metairie and Mandeville. For more information please call 985-869-8400 or 504-502-7600.

Dr Krista Varady, University of Illinois
Dr Sandrine Thuret, Neuroscientist
Dr Mark Mattson, National Institute on Aging

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