Intermittent fasting has been around for years, but it has been more recent that it has gained popularity and notoriety from health experts around the world. With its robust health benefits, more and more individuals are turning to intermittent fasting as a way to optimize their long-term wellness goals. Plus, when you hear celebrities, famous podcasters, and even fitness icons touting how it has changed their life, you start to wonder what the buzz is all about.
We’re here to answer those very questions on intermittent fasting, as well as give more insight as to its effect on men and women. Let’s check it out!
Does Intermittent Fasting Work For Men
Genetics plays a major role in intermittent fasting for men vs. intermittent fasting for women when it comes to an overall increase of the metabolism.
Research shows that a males overall physical size and body composition are key factors in yielding a higher metabolic response with intermittent fasting than that of their female counterpart. This can be traced back to the “hunter-gather” days; the increase in metabolism gave the necessary fuel for man to hunt when food was scarce. On the other hand, women tend to store and conserve as a means for survival.
Another study found that during short fasting periods, up to a 14% increase in metabolism was most common in healthy males, as well as an increase in both testosterone utilization and growth hormones.
Benefits Of Intermittent Fasting For Men
While improved body composition is one of the most desired benefits of intermittent fasting for men, the overall health advantages it yields goes way beyond what the number on the scale reads. Here are a handful of ways that intermittent fasting has been shown to have significant improvements on men’s health:
- Longer life span
- Faster tissue & cell rejuvenation
- Metabolism & physical fitness
- Brain function and reduced risk of Alzheimer’s disease
- Decreased risk for high blood pressure & Type II diabetes
- Heart health
- Cancer prevention
Benefits of Intermittent Fasting For Women
The benefits of intermittent fasting for women are slightly different than that of men. While this will be discussed momentarily, it is important to know that women may have more success with intermittent fasting by taking a less aggressive approach. One of the best ways you can think about it is “less is more.” Think shorter, less frequent fasts and, most importantly, listen to your body! Some of the positive health benefits women may experience from fasting are the following:
- Improved mood
- Body confidence
- Change in body composition and muscle mass
- Decrease in inflammation throughout the body
- Reduce the risk of heart disease
- Be more in tune with hunger levels
- Reduce risk (or manage) diabetes
Intermittent Fasting Schedule For Men
Just like there is no “one size fits all plan,” fasting schedules are going to be entirely individual too. The following are a handful of intermittent fasting schedules for men that can be modified to be more conducive intermittent fasting schedules for women. As highlighted above, it’s recommended women take a slower approach to start, and adjust accordingly.
- 12 hour fast
- 16 hour fast
- 2 days per week fast
- Alternate day fasting
- 24 hour fast
- Meal skipping
- The Warrior Diet
Now that you have an idea about the many ways you can go about doing a fast, let’s see what happens when the body is actually on a fast. Different from what was just discussed, we are going to do a quick overview of a 72 hour (extended) fast, and what happens during each one of its stages.
- Stage 1 (12 Hours): The body breaks down food to convert into glycogen; when this is present, this will be the 1st source of energy in the body. This is also the time in which a change in insulin levels will occur. Post eating, insulin levels rise, signaling the body to break down glucose. After a 12 hour fast, insulin levels will drop, eliminating the feeling of fullness (aka leptin) but increasing the hormone that signals hunger (aka ghrelin).
- Stage 2 (18 Hours): It takes anywhere in the 4 to 18 hour window for your body to burn any stored glycogen that is present. This is when your body begins to go after another fuel source for energy, and will start tapping into any stored body fat and proteins (i.e. amino acids) to survive. After the 18 hour window, though, your body will solely rely on stored fat. This process is known as ketosis. Insulin levels remain low but the hormone that regulates blood glucose levels (aka glucagon) will start to rise as a way to make sure levels do not get too low.
- Stage 3 (24 Hours): A process called autophagy happens at this point; this is when the repair process begins and your body starts eliminating parts of cells that are not working properly, old, and/or even damaged. This is a bit of a turning point since this is a key factor in reducing inflammation, destroying cancer cells, and has even been linked to preventing Alzheimer’s disease.
- Stage 4 (48 Hours): Now we are in a long-term fasting state and 2 things start to happen – growth hormone levels increase, helping to preserve lean muscle mass, and hunger levels begin to even out as well.
- Stage 5 (52 Hours): Insulin levels are at their lowest which, actually, helps with reducing inflammation, improving body composition, and continuing with the process of autophagy (as discussed in Stage 3).
- Stage 6 (72 Hours): Think about a whole new refresh for your system! Your IGF-1 (aka insulin growth factor) hormone will start to decrease which, in turn, creates new stem cells, immune cells, and decreases the amount of tissue and cell stress on the body.
Intermittent Fasting Schedule for Women
In general, it is ideal for women to take a more relaxed approach when it comes to introducing a fast. Just like we highlighted for men, here are a few of the options that work well for women to adapt.
- 16 hour fast, also known as the 16/8 Method
- 24 hour fast, no more than 2 times per week
- 2 days per week fast; restrict calories to about 25% of your usual daily intake (you will still be eating but minimally speaking) and on your non-fast days you eat as normal
Cons Of Intermittent Fasting For Men vs. Women
While the standard fasting styles you heard about are designed by men, for men, women can still gain the same health benefits by staying mindful of any hormonal and metabolism shifts.
- When a change in nutrient consumption takes place, women react differently than men due to a protein-like molecule that directly affects the hormones that regulate hunger, cravings, and feelings of satiation. This is called “kisspeptin,” and it is necessary in the reproductive process. Since women have more kisspeptin than men, when fasting, these levels drop and a disruption in the hormonal cycle, and shift in energy balance, occurs.
- Nutrient restriction can have an effect on women’s menstrual cycles, especially if there is an inadequate amount of protein in the diet. Protein is composed of essential amino acids that are necessary for the reproduction process. If amino acids get too low, this can greatly affect estrogen and insulin-like growth receptors.
- A decrease in estrogen levels – which happens during fasting – can affect mood, hunger, body composition, metabolism, sleep, stress, digestion, etc. By keeping a close eye on the physical and physiological effects you experience, this will help determine the best way you can tweak your fasting approach for the best results.
The Bottom Line
While gender does play a role in how intermittent fasting affects the metabolism, the numerous health benefits it provides make it a desirable approach for anyone who wants to level up their wellness game! Intermittent fasting is more than just a trendy fad; it is a lifestyle approach to achieving total body health!
Sources:
1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4516560/
2. https://www.healthline.com/nutrition/intermittent-fasting-metabolism#TOC_TITLE_HDR_4
3. https://www.healthline.com/nutrition/10-health-benefits-of-intermittent-fasting#TOC_TITLE_HDR_9
4. https://www.healthline.com/nutrition/intermittent-fasting-for-women#effects-on-women
5. https://www.healthline.com/nutrition/warrior-diet-guide
6. https://www.precisionnutrition.com/intermittent-fasting-women#response