TODAY'S FEATURED DIET: INTERMITTENT FASTING (IF)
Friday, July 12, 2019
I follow the DASH Eating Plan but have taken interest in knowing more about other ways of eating (WOE). Primarily because 1) I am nutrition focused and like to learn more on what makes a healthy WOE, 2) Want to be able to offer educated suggestions to family and friends based on their health goals, 3) understand other's point of view more regarding their chosen WOE, and 4) offer some diversity.
Today, I am writing about intermittent fasting and it's use in weight loss. I think this is the third largest group I have encountered online and so I decided to see what it is all about.
My primary source for diet plans is USNews and World Report. Intermittent fasting in of itself is not really a diet/eating plan per se. It is more about timing and less about types of foods. How people chose to implement IF varies widely...especially since we all do it to an extent intentionally or unintentionally. Because of this, IF is unranked by USNews. However, one variation the 5:2 Diet is. I will be discussing IF as a whole, but just for informational purposes - the 5:2 diet is #25 as best fast weight loss diet, #26 in easiest diets to follow, #31 as best weight loss diet, #34 best diets for healthy eating, and #36 as best diabetes diets.
WHAT IS INTERMITTENT FASTING:
An eating pattern that cycles between periods of fasting and eating. It doesn’t specify which foods you should eat but rather when you should eat them. Common intermittent fasting methods involve daily 16-hour fasts or fasting for 24 hours, twice per week.
Fasting has been a practice throughout human evolution. Ancient hunter-gatherers didn't have supermarkets, refrigerators or food available year-round. Sometimes they couldn't find anything to eat. As a result, humans evolved to be able to function without food for extended periods of time.
In fact, fasting from time to time is more natural than always eating 3–4 (or more) meals per day.
Fasting is also often done for religious or spiritual reasons, including in Islam, Christianity, Judaism and Buddhism.
IDEAL FOR: Anyone not mentioned below if it works for you, Minimalist, Busy People
NOT GOOD FOR: People who are underweight or have an eating disorder, Women trying to conceive, Pregnant/Breastfeeding women, Those on certain medications, Those with low blood pressure, Diabetics
HOW DOES IT WORK:
If you've ever eaten dinner, then slept late and not eaten until lunch the next day, then you've probably already fasted for 16+ hours.
There are several different ways of doing intermittent fasting — all of which involve splitting the day or week into eating and fasting periods.
During the fasting periods, you eat either very little or nothing at all.
These are the most popular methods:
The 16/8 method: Also called the Leangains protocol, it involves skipping breakfast and restricting your daily eating period to 8 hours, such as 1–9 p.m. Then you fast for 16 hours in between.
Eat-Stop-Eat: This involves fasting for 24 hours, once or twice a week, for example by not eating from dinner one day until dinner the next day.
The 5:2 diet: With this methods, you consume only 500–600 calories on two non-consecutive days of the week, but eat normally the other 5 days.
By reducing your calorie intake, all of these methods should cause weight loss as long as you don't compensate by eating much more during the eating periods.
Many people find the 16/8 method to be the simplest, most sustainable and easiest to stick to. It’s also the most popular.
Aim for 50 grams of healthy protein from sources like steamed white fish, skinless chicken, tofu, nuts, seeds, legumes and eggs. Round out your meal, meals or snacks with low-calorie, fiber-rich and nutrient-dense fruits and vegetables.
When you fast, several things happen in your body on the cellular and molecular level. Your cells also initiate important repair processes and change the expression of genes.
Here are some changes that occur in your body when you fast:
Human Growth Hormone (HGH): The levels of growth hormone skyrocket, increasing as much as 5-fold. This has benefits for fat loss and muscle gain, to name a few.
Insulin: Insulin sensitivity improves and levels of insulin drop dramatically. Lower insulin levels make stored body fat more accessible.
Cellular repair: When fasted, your cells initiate cellular repair processes. This includes autophagy, where cells digest and remove old and dysfunctional proteins that build up inside cells
Gene expression: There are changes in the function of genes related to longevity and protection against disease.
By making you eat fewer meals, intermittent fasting can lead to an automatic reduction in calorie intake.
Additionally, intermittent fasting changes hormone levels to facilitate weight loss.
In addition to lowering insulin and increasing growth hormone levels, it increases the release of the fat burning hormone norepinephrine (noradrenaline).
Because of these changes in hormones, short-term fasting may increase your metabolic rate by 3.6–14%.
By helping you eat fewer and burn more calories, intermittent fasting causes weight loss by changing both sides of the calorie equation.
BENEFITS: Boosts metabolism*, Reduce Insulin Resistance, Promotes Cellular Repair, Reduces Inflammation, Anti-aging**, Less Meal Planning/Prepping, Causes less muscle loss than regular calorie restriction, Few Rules/Freedom/No Food Restrictions
* Studies show that short-term fasts actually boost metabolism. However, longer fasts of 3 or more days can suppress metabolism
** Seen in animal studies but not confirmed in humans
SHORTFALLS: Amenorrhea (absence of menstruation), Hunger, Light-headedness/Brain Fog, Not Family Friendly, No Focus on Nutrition, Hypoglycemia in Diabetics, Does not promote changed behavior or lifestyle habits
I highly encourage anyone interested to read the three peer-reviewed articles below. The healthline website also has links to other peer-reviewed studies.