Intermittent fasting and time restricted eating is all of the rage right now. Who wouldn’t want to skip a meal and then be able to eat whatever you want? That is the common perception but not exactly true. The type of fasting and how and what you eat between the fasting can make a difference. So, what are the most common types of fasts and what can you expect from them?

Symbolizing intermittent fasting with food displayed on plate as a clockTwo Major Types of Fasting

  • Intermittent fasting is defined as fasting for less than 2 days a week
  • Prolonged fasting is fasting more than 2 days a week.

Types of Intermittent Fasting

  • Time Restricted Eating: TRE is 12:12– 12 hours to eat and 12 hours to fast or 8:16 -8 hours to eat and 16 hours to fast and 6:18 – 6 hours to eat and 18 hours are the most common regimens
  • Eating 5 Days and Fasting for 2 days known as 5:2
  • Alternate Day Fasting

Two types of Prolonged Fasting

  • Water fast
  • Fasting Mimicking Diet

Fasting doesn’t have to be a complete water fast. Restricting calories on the fast days to 500-600 calories is sufficient to stop the signaling pathways that food produces.

The regimen you choose depends on your goals.

  • Skipping breakfast is associated with obesity, daily breakfast eaters were less likely to have CVD risk factors, including elevated serum low-density lipoprotein (LDL) cholesterol, low serum high-density lipoprotein (HDL) cholesterol, and elevated blood pressure.
  • Skipping breakfast has been associated with markers of impaired sugar metabolism, including elevated hemoglobin A1c a marker for blood sugar over 30 days and higher fasting blood sugar and all-day post meal blood sugar elevations.
  • Breakfast skippers had a higher rate of diabetes, heart disease and stroke.
  • The best weight loss occurs with alternate day fasting or prolonged fasting
  • A circadian 12:12 is most in tune with our biological clocks and hormone cycles.
  • Blood pressure drops correlate with weight loss
  • Intermittent fasting’s effect on lowering cholesterol is variable but prolonged fasting shows a greater improvement.
  • Reductions in insulin, blood sugar and insulin resistance occurred in some studies for intermittent fasting and were more reliably reduced with prolonged fasting.
  • A 6:18 hour fast may increase longevity and stress resistance and decrease the incidence of cancer and obesity by switching energy sources from glucose to ketones.
  • The Fasting Mimicking Diet FMD was shown to improve longevity by cleaning out old dead cells (autophagy) and increasing stem cells that regenerate and repair tissues.
  • FMD lowers IGF1. A high IGF1 increases the risk of cancer and accelerates the aging process.
  • The Fasting Mimicking Diet improves blood sugar, lipids, weight, insulin resistance and decreases inflammation.
  • The Fasting Mimicking Diet preserved muscle mass as well as reduced the above mentioned cardiometabolic risk factors and showed a positive effect on Autoimmune disorders such as multiple sclerosis, Chron’s.

Timing is EVERYTHING!

We have biological clocks in all of our organs and the most well-known clock is the day night clock. Many of our hormones are in rhythm with this clock. When we eat out of rhythm with day, night cycles, the disruption can lead to hormone dysregulation and stress on the mind and body. Eating out of synche will reset the clocks in your organs and uncouple the organ clocks from the master clock. Imagine being in a car wash and the drying occurred first, the car moves backwards then forward and the whole process becomes disrupted to a point where the goal is not accomplished.

Your Bio Rhythms

Daytime

  • During the day our liver makes glycogen, the storage form of sugar that needs to be readily available and replenished. The liver also makes cholesterol needed for hormone production and making cell walls and also makes bile acids to digest fat, remove toxins and sanitize the bowels, the pancreas makes insulin that drives sugar into your cells to be burned as a fuel source, fat is burned, and fat produces adiponectin a hormone that increases insulin sensitivity and regulates sugar and fat metabolism.

Nighttime

  • The liver makes glucose from fat and proteins, the pancreas makes glucagon, a hormone that raises blood sugar to keep you fed at night and allow all of your cells and organs to have the energy for regeneration and repair as well as to maintain normal function, your fat breaks down lipids and secretes leptin which makes you feel satisfied and full so you don’t eat and don’t disrupt the hormone cycles.

Eating out of alignment with this clock

  • Decreases leptin the hormone that makes you feel full and satisfied – this will give you cravings and cause you to overeat
  • Promotes high blood sugar responses after a meal in the range typical of a prediabetic state.
  • Increases blood sugar despite increased insulin
  • Increases blood pressure
  • Reduced sleep efficiency
  • Late night eating increased cardiometabolic risk
  • Meals consumed at night increase blood sugar after meals and increase insulin leading to increased HbA1c levels and risk of type 2 diabetes over time.
  • Insulin sensitivity decreases throughout the day and into the night so late-night eating will drive insulin up and increase fat storage.

The Bottom Line

While there are not enough studies to compare the different time restricted eating regimens, you may want to try different eating patterns. The 12:12 circadian pattern is most in line with our biological clocks and is the easiest to do. Studies do show it would be best to eat during the day, make breakfast your biggest meal and choose a plan that you can stick to. If your goal is some weight loss and blood sugar regulation, try time restricted eating.

If your goal is longevity and regenerating stem cells as well as lowering blood sugar, lipids, cholesterol and decreasing inflammation, 3 rounds of the Prolon Professional Fasting Mimicking Diet done once a month for 3 months has been shown to accomplish these goals. Some people may need to do it more or less often if their metabolism is stuck. There are some people for whom this diet would be detrimental; find out more here.

Be sure to eat a healthy diet in between fasts and not overcompensate. If you are interested in doing the Prolon Professional Fasting Mimicking Diet, you can purchase it on the Get Healthy Store. Occasional fasting is the key to health and longevity.