Ready to get started on a New Year of improved health?
Ready to start turning back your biological age clock?
Cue fasting! The health benefits can be amazing. Not only did one study show a Biological Age Reversal by 2.5 years in one year after doing 3 cycles of the fasting mimicking diet but look at all the other potential benefits:
Potential benefits a fasting mimicking diet:
- Fat burning
- Mental clarity
- Decrease in inflammation markers
- Heart health
- Insulin resistance improvement
- Reduction of visceral fat
- Weight loss
- Increase in good bacteria in the gut
- Skin improvements
- Cellular cleaning (autophagy): this is when cells recycle intracellular debris, worn-out parts and toxins and repurpose them into newer reusable parts. They appear to be younger versions of themselves after the fast.
You’ve read and heard about fasting and I’m sure you might have even tried some intermittent fasting limiting the window you are actually eating called time-restricted eating. However, the true studies on fasting involve longer fasts with so many added benefits we thought it would be worth trying. We are doing the Prolon fast in our office so join us!
Let’s learn more about fasting.
So why aren’t more people doing this? Because it is HARD!! This is one of the reasons studies have looked at other ways to get this benefit evaluating everything from caloric restriction to varied times of time restricted eating. Here are some of the terms you might hear….
- Sustained fasting: Fasting more than several days in a row
- Time-restricted eating: this is a version of intermittent fasting. Reducing the amount of time during the day you are eating and fasting on average 14-18 hours depending on your window of eating.
- Alternate day fasting: Simply means one day you fast, the next day you don’t.
- 5:2 diet: Fasting for 24 hours twice a week and often includes restriction of calories to 75% or less than 500 calories during those two 24 hour segments.
- Calorie restriction: reducing your calories on a daily basis but not paying attention to timing. This is not fasting.
- Fasting mimicking diet: Any fast that mimics fasting but still allows food intake
READ ON to learn more about what pitfalls there are to fasting (hint – thyroid is one of them) and how fasting compared to calorie restriction….
The first order of business is to address simple calorie restriction. Turns out simply reducing your calories does help with weight loss, insulin resistance and cardiovascular health parameters however not as much as intermittent fasting!!
Does that mean you get to eat whatever you want as long as you are eating during a smaller window?
Umm, short answer… NO!! A small study looked at eating three meals evenly spaced out during the day vs eating the exact same three meals within a specified restricted eating window of four hours. After two months, there were some slight changes. The time restricted people did have a slight change in body fat mass but an increased LDL and blood pressure. Take home message here, if you are not going to change your diet eating regularly spaced out meals is preferable. Further studies show erratic eating (sometime you eat dinner at 5 and sometimes you eat at 10pm etc) may actually increase the risk of disease!
There is a key “metabolic switch” that occurs during a fast when the body literally depletes the liver glucogen stores and starts metabolizing fatty acids derived ketones. In the non-fasting state insulin is the main hormone driving the body to use glucose as fuel but in the fasting state glucagon is the primary hormone driving the body to use the liver stores of glycogen for energy. This metabolic switch typically occurs around 12 hours after the cessation of eating and continues as long as the body is in fasting state. This entire process shifts the metabolism from cholesterol/lipid synthesis and fat storage to the mobilization of fat preserving both muscle mass and function. This is why fasting and intermittent fasting regiments have the potential to improve body fat composition in people who are overweight. If you are doing an 18 hour per day fast then you would have 6 hours of fat burning activity due to this metabolism switch.
What do the studies show when comparing time-restricted fasting (TRF) to calorie restriction (CR) alone?
- CR does improve insulin resistance, promote weight loss, improve cardiovascular health
- CR may have 14/ to 1/3 of the weight loss to be of lean tissue vs TRF (16 hours) showed reduction in fat mass with retention of lean mass and strength. This study was over two months with the addition of a standard resistance training program.
- TRF but not CR increases the gut microbiome diversity and recently shown to increase a bacteria species thought to be important in longevity (Christensenella species).
Fasting is not for everyone though. Here are some potential side-effects to be aware of:
- Electrolyte imbalances that can be severe
- Blood sugar drops especially in diabetics
- Low blood pressure
- Thyroid hormone dysregulation if fasting for prolonged periods of time (Studies on Ramandan fasts indicate thyroid medication may need to be altered during prolonged fasts)
- Other hormonal imbalances. For pre-menopausal women, fasting the week after your cycle seems to be preferable and easier than fasting the week prior to the cycle.
- Side-effects associated with significant changes in your diet including constipation, headache, fatigue and brain fog to name a few.
There are a whole host of conditions that you should avoid fasting if you have any of them. See the list below:
- Pregnant
- Breastfeeding
- Eating disorder
- Cancer
- Congestive heart failure
- History of fainting
- Over 65 years of age without doctor’s consent
- Active infection
- Upcoming surgery or recent surgery
- Ongoing significant medical treatment like chemotherapy
If in doubt ask your physician if fasting is appropriate for you.
How do you survive a fast?
While fast literally means nothing to eat because of the potentially serious side-effects this should not be attempted without supervision. This is why most fasting programs actually recommend specific soups, snacks and low calorie foods that do not spike the blood sugar levels to help you maintain a fast safely. Simply adding approved extra fats like MCT oil or sometimes even heavy cream can go a long way.
To your health,
Laura