Intermittent Fasting: Everything You Need to Know!
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Intermittent Fasting (IF) has become increasingly popular with the keto-craze. I was curious about it and dug into the research to find out who it is for, how to do it, and what the benefits may be. I was surprised at what I found, which ultimately led me to steering clear of IF altogether.
What is Intermittent Fasting?
Intermittent fasting is when you split your day into a "fasting" window and an "eating" window. This usually looks like 16 hours of fasting, 8 hours of eating. This is the most common type of IF, but others may choose to do a full 24 hour fast one to two times per week instead. It’s not intended to be a “diet” per se but rather an eating pattern.
It’s easy to think “I’m going to lose weight because I’m skipping breakfast” but that’s actually not the goal. With IF, you are not cutting calories out of your diet, you’re just consuming them within a certain amount of time.
How Intermittent Fasting works
Following a meal, your body uses the food you just ate as energy, especially carbohydrates. However when you fast, your body uses your stored body fat as energy since it is not getting fuel from your empty stomach. As a result, using fat for energy = fat loss. You may hear the term “fasted cardio” a lot which refers to working out first thing in the morning to burn even more fat for energy rather than food (theoretically, the research is spotty). Your body is most sensitive to insulin following a fast, meaning you are better utilizing your food which leads to weight loss and muscle gain.
The Pros
Research has shown that IF can lead to:
Increased insulin sensitivity
Reduced risk of chronic diseases like diabetes, heart disease, and cancer
Increased ability to burn fat for fuel
Decreased inflammation and free radical damage
Decreased weight gain
The Cons
As we all know, men and women have different hormones and the whole premise of fasting is to impact hormones in a positive way. However, there is very little research on the effects of intermittent fasting on women, especially those who are of reproductive age.
Studies show that men see wonderful benefits from IF. On the contrary, many women who have tried intermittent fasting experience:
Hair loss
Weight gain
Acne
Excess body hair
Decreased libido
Low energy
Anxiety
Irregular periods
Brain fog
The truth is, we don’t know exactly how IF affects women because the research just isn’t there. Of the research done on women, the subjects are obese and not of reproductive age. These women show some favorable outcomes on IF and if you identify with those two categories, IF may be worth a shot. However, for women of average weight who are looking to “lean out” or “tone up,” I would be wary of the benefits. Self experimentation is the best way to find out if IF works for you, but do so with caution.
In the studies that compare women and men undergoing IF, women do not see the same insulin sensitivity that men do. They actually saw adverseeffects on glucose tolerance in women, but not men. Rat studies have shownmostly unfavorable results in females and good results in males.
Anecdotal evidence has shown that intermittent fasting can become addicting due to a “high” of energy and mental clarity that comes after fasting. Men and women with a history of disordered eating should only attempt intermittent fasting if under the direct supervision of a doctor.
The Takeaway
Intermittent fasting may be a good way to decrease body fat, prevent disease, and clean up inflammation if you’re a male or an obese woman post-menopause. However, if you are a woman of reproductive age and average body weight and decide to give it a go, proceed with caution and take note of changes in mood, skin, and menstrual cycle.