Drawbacks of Intermittent Fasting

#1) If you skip breakfast, you might be so hungry from missing that morning meal that you OVEREAT your other meals, which can lead to weight gain. 

The important thing here is that with an intermittent fasting plan (or really any diet plan), you’re eating fewer calories than normal because you’re skipping a meal or possibly 2 every day (if your goal is weight loss.)

Please don’t convince yourself into thinking that if you skip breakfast and then eat 4,000 calories of candy bars and chips for lunch and dinner that you will lose weight. This is a simple math, habit and behavior strategy for giving yourself fewer chances to overeat and put your body into a caloric surplus.

 

#2) Skipping meals can result in feelings of lethargy, hunger, and being hangry!

Be gentle with yourself if you eat breakfast every morning; your body expects to wake up and eat food. Once you retrain your body to NOT expect food the first thing in the morning, it’s possible that these side effects become less of an issue. FYI, ghrelin (a hormone that makes you hungry) is actually lowest in the mornings and decreases after a few hours of not eating.

 

#3) Intermittent Fasting can be more complex for folks who have issues with diabetes, blood sugar regulation, suffer from hypoglycemia, have hormone issues, etc. 

If you fit into this category, check with your doctor before adjusting your eating schedule.

 

#4) Intermittent fasting effects men and woman differently.

A recent PubMed summary concluded: “Fasting can be prescribed as a safe medical intervention as well as a lifestyle regimen which can improve women’s health in many folds.”

Many studies cited they are focused on specifically calorie restriction (and not just fasting), and they also mention that “future studies should address this gap by designing medically supervised fasting techniques to extract better evidence.”

After digging into the PubMed Archives a bit more, it brought me to the following conclusions:

One small study tracked 8 men and 8 women (all non-obese) and resulted in the following: “Glucose response to a meal was slightly impaired in women after 3 weeks of treatment, but insulin response was unchanged. Men had no change in glucose response and a significant reduction in insulin response.”

Another small study tracked 8 women and the effects on their cycles after a 72-hour fast: “In spite of profound metabolic changes, a 72-hour fast during the follicular phase does not affect the menstrual cycle of normal cycling women.” 

Yet another study tracked 11 women with 72-hour fasts: “Fasting in women elicited expected metabolic responses – included increased cortisol (a stress hormone) – and apparently advanced the central circadian clock (which can throw off sleeping patterns).”

 

Those studies were working with small sample sizes, and different types of fasting. It leads me to believe that fasting affects men and women differently, and that many of the weight loss benefits associated with intermittent fasting (that affect insulin and glucose responses) can work positively for men and can possibly work against women’s hormones/health. However, some of my female clients swear by intermittent fasting and have great results.

 

I recommend NOT attempting Intermittent Fasting if you:

• Have a history of thyroid or gall bladder issues
• Are pregnant, planning on being pregnant in the near future or are breast feeding
• You have a history of an eating disorder
• Are chronically stressed
• Don’t sleep well
• Are new to diet and exercise
• Are sick (fasting can deprive your body of the steady stream of nutrients that it needs to heal and get better).
• Are a child or teenager

 

The challenge associated with all of this is that there aren’t enough long-term studies, with large enough sample sizes, specifically targeting females, with relation to the different types of intermittent fasting.

 

It does appear that men and women will have different experiences with intermittent fasting; we’re all unique snowflakes (yes - especially you), and your body will be affected by intermittent fasting differently than the person next to you.