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Is breakfast really the most important meal of the day? Or, is that idea just something we’ve been sold told? It is possible you could look, feel, and perform better if you break up with breakfast and try fasting instead? Read on and find out!

A Brief History of the American Breakfast

Throughout history, breakfast has played a prominent dietary role in some cultures, and not in others.

In America, it’s just been the past 100 years that breakfast’s reputation has grown to become “the most important meal of the day.”

From what I found, Lenna Cooper gets the credit for breakfast’s reputation. In a 1917 issue of Good Health, she wrote, “…breakfast is the most important meal of the day, because it is the meal that gets the day started.”

Coincidentally (or perhaps, not a coincidence…you can be the judge), Dr. John Harvey Kellogg was an editor. He was also the co-inventor of flaked cereal.

And so began breakfast’s reputation, paving the way for food companies to capitalize.

Breakfast cereal advertising has dominated food advertising for decades. Of course, cereal isn’t the only breakfast option. Toast, orange juice, waffles, pancakes, and toaster pastries are other common foods people eat for breakfast. None of these are necessarily healthy, although the packaging would lead you to believe they are.

High-protein options like eggs, meat, and nuts, or protein shakes are a lot healthier, but they’re not the norm.

For those who don’t eat breakfast at home, McDonald’s is the most common fast-food choice. Their launch of the Egg McMuffin in 1971 set McDonald’s up to dominate the fast-food breakfast market. Today, they own almost a fifth of the market share.

Is Breakfast the Most Important Meal of the Day?

Like many health and nutrition recommendations we’ve been sold told, the health benefits of breakfast are based on correlations.

When researchers identify patterns of behaviors occurring together, they sometimes believe that one causes the other.

This happens with health and nutrition research ALL…THE…TIME!

Here’s a perfect example.

I received this article as part of my Science Daily newsletter recently. The title of the article is Skipping breakfast associated with hardening of the arteries. The emphasis is mine.

People who regularly skip breakfast likely have an overall unhealthy lifestyle,” said study author Valentin Fuster, MD, PhD, MACC director of Mount Sinai Heart and editor-in-chief of the Journal of the American College of Cardiology.” This study provides evidence that this is one bad habit people can proactively change to reduce their risk for heart disease.

Researchers in Madrid examined male and female volunteers who were free from cardiovascular or chronic kidney disease. A computerized questionnaire was used to estimate the usual diet of the participants, and breakfast patterns were based on the percentage of total daily energy intake consumed at breakfast. Three groups were identified — those consuming less than five percent of their total energy intake in the morning (skipped breakfast and only had coffee, juice or other non-alcoholic beverages); those consuming more than 20 percent of their total energy intake in the morning (breakfast consumers); and those consuming between five and 20 percent (low-energy breakfast consumers). Of the 4,052 participants, 2.9 percent skipped breakfast, 69.4 percent were low-energy breakfast consumers and 27.7 percent were breakfast consumers.

Atherosclerosis was observed more frequently among participants who skipped breakfast and was also higher in participants who consumed low-energy breakfasts compared to breakfast consumers. Additionally, cardiometabolic risk markers were more prevalent in those who skipped breakfast and low-energy breakfast consumers compared to breakfast consumers. Participants who skipped breakfast had the greatest waist circumference, body mass index, blood pressure, blood lipids and fasting glucose levels.

Participants who skipped breakfast were more likely to have an overall unhealthy lifestyle, including poor overall diet, frequent alcohol consumption and smoking. They were also more likely to be hypertensive and overweight or obese. In the case of obesity, the study authors said reverse causation cannot be ruled out, and the observed results may be explained by obese patients skipping breakfast to lose weight.

That breakfast is the most important meal of the day has been proven right in light of this evidence.

Do you see the flaw in the logic? Those who skip breakfast are more likely to drink alcohol frequently and to smoke. They’re also more likely to be overweight or obese.

Breakfast-skipping is guilty by association, not by causation.

Will eating breakfast stop the smoking, drinking, or other unhealthy lifestyle habits? Apparently, the authors of the paper above think so, but I do not.

What is Intermittent Fasting?

Fasting is not new, although the enthusiasm for its ability to improve health is.

Almost every religion incorporates fasting into their faith in some way.

To fast means to go without food (or calorie-containing beverages).

In some cases, fasting might include going without water as well. However, when it comes to health-related fasting, non-caloric beverages like water, tea, coffee, or diet drinks are permissible.

Intermittent fasting is an eating pattern where you go without food long enough to have a metabolic effect.

Eating before bed, sleeping for eight hours, and then getting up to eat breakfast does not qualify, even though the name breakfast suggests that you “break a fast.”

Types of Intermittent Fasting

Ramadan fasting is the most-studied form of intermittent fasting. Followers of Islam fast from sunrise to sunset for 29-30 days, once per year.

Because they adhere to this fasting practice so well, and because it affects such a large number of people, they make an excellent population subgroup for research.

Alternate-day fasting is another form, where you eat whatever you want one day (feast), and then avoid food the next (fast). Some people fast two days per week, like on a Wednesday and a Saturday instead, and eat on the other five days.

Personally, the idea of going without food for an entire day, unless it was for religious reasons, sounds dreadful to me.

I like to eat. I also want to be able to workout, and I don’t think it’s a good idea to train intensely if you’re unable to eat at some point later that day.

I sort of drifted into another form called time-restricted feeding (TRF). In this type of intermittent fasting, you can still eat each day, it’s just within a shortened window of time.

For a few years, I had the luxury of being able to workout at lunchtime instead of first-thin in the morning. When I started working out a lunchtime, I decided to just drink coffee and skip breakfast in the morning.

The longer I waited to eat, the more productive and clearheaded I felt. Eventually, I started skipping breakfast altogether, and waiting until after my training session to eat my first meal.

Though I wasn’t intentionally trying to get leaner, I did. Ironically, I found that I was eating more food when I did eat than I had in the past. And more carbs, too.

My daily daily routine looked kind of like this:

  • ~6:00 am: Wake and drink several cups of coffee and water throughout the morning.
  • ~12:00: Training Session
  • ~1:30 pm: Lunch: Lots of meat and vegetables, my supplements (including The Foundational Five), and at least a serving of dark chocolate. Then, back to work.
  • ~7:00: Eat a huge dinner, which includes at least 12-16 ounces of meat, turkey, bison, etc., and a lot more carbs.  Supplements. Most nights, a pint of Halo Top ice cream or something else with some sweetness.

Read more: High-Protein Diets: Health Benefits and Controversies.

Does this seem boringly simple? It really is, and that’s why I like it so much.

In the past, I weighed and measured my food, took time for food prep, ate every few hours, and logged what I ate.

I felt like I organized my life around my diet. Who has time for that?

With nutrition, you can reach a point of diminishing returns. Would weighing and measuring everything help drop an extra point or two in body fat percentage? Probably. But would the extra effort and time be worth it? Not for everyone.

If you can stay healthy and lean, and perform well physically and mentally, by just eating a couple of times per day (of course, it’s high in protein and gluten-free), why would you make it more complicated than that?

One other thing I should note. I no longer have the luxury of mid-day training sessions. I need to workout in the morning.

If that’s your case, and you’d like to do intermittent fasting, you can get close to the same benefit by using only essential amino acids following your workout, and still waiting until lunch to eat a meal.

Two to four servings of Life Time Amino Complex or BCAA Recovery will carry you through the morning without sacrificing the gains you’ll make from your workouts.

Psychological Advantages of Intermittent Fasting

Intermittent fasting is more of a lifestyle than a diet.

Diets are eating patterns we follow for a short period of time. They often require considerable willpower, which is why they have such an incredibly low success rate.

On a traditional diet, each time you eat, you face a decision about whether to eat what you should eat or to eat what you feel like eating.

With intermittent fasting, there’s no decision to be made about what to eat when you’re most likely to make a poor decision. You just don’t eat.

Researchers have found this to be the case as well. Adherence to intermittent fasting is much better than other “diets.”

Try it tomorrow morning. When you walk into your kitchen at your usual breakfast time, instead of asking, “What should I eat for breakfast?” simply say out loud, “I don’t eat breakfast.”

Eliminate the opportunity to be tempted, and you save yourself from making a poor decision.

Read more: Why Meal Plans Don’t Work.

Health Benefits of Intermittent Fasting

If intermittent fasting were equally effective as other diets, I’d still recommend people try it, since it’s easier to stick with. However, a growing number of studies show that it could actually be superior.

Most of the research below is based on humans. There are many other studies on animals, even suggesting that intermittent fasting could prolong lifespan. However, animal research doesn’t always translate to humans.

So, the only animal research I mention is related to cognitive function, because nobody will volunteer to be given a stroke so researchers can see how well intermittent fasting helps in the recovery process.

1. Weight Loss

In my opinion, fasting is more effective for managing calorie intake than eating in moderation.

Most people who have struggled to lose weight are already frustrated with trying to “stick to a diet.”

As I mentioned above, eliminating a meal, or even a day of eating is a firm decision. Eating multiple times each day, and dealing with the temptation to eat something other than you should, sets you up for failure.

Intermittent fasting supports weight loss in a few other ways.

First, most people do not make up for missed meals by eating more during the feeding period.

They end up eating fewer total calories.

Second, the longer they go without food, the more they’ll draw on body fat stores to meet their energy needs.

Fasting extends the time at which you use primarily fat for fuel. Since you don’t eat, you don’t raise blood sugar and insulin, which would shut down your ability to burn fat.

Third, some studies have shown that when people eat an equivalent number of calories, protein, fat, and carbohydrates, but they eat it within a shortened window of time, they can lose weight.

That’s worth repeating: Consuming the same amounts of protein, carbohydrate, and fat, but consuming them in a shortened window of time, may decrease body fat levels.

The only way this could happen is if intermittent fasting causes unique metabolic changes.

One theory is that intermittent fasting increases adiponectin, which increases metabolic rate. Another possibility is that the fasting stimulates epinephrine secretion, which would also raise resting metabolic rate, but this has not been proven yet.

For overweight individuals with type 2 diabetes, a time-restricted fasting protocol for just two weeks caused a significant reduction in body weight, fasting glucose and post-meal increases in blood sugar, which leads me to the metabolic health benefits of intermittent fasting.

2. Metabolic Health

During a period of fasting, your blood sugar remains steady. Without ingesting carbohydrates or protein, your blood sugar does not rise, and insulin levels remain low.

This could be an especially-appealing dietary choice for those with insulin resistance or diabetes, which affects about two-thirds of the population.

Though some doctors believe that type 2 diabetes is a “disease” and it can never be “cured,” I very much disagree. You can easily remove the cause of insulin resistance and diabetes through nutrition and lifestyle choices, which means it’s not a disease. It’s a condition caused by personal choices. And the condition can be “cured” by dealing with the cause.

Just a few months of intermittent fasting can dramatically improve one’s insulin sensitivity.

Intermittent fasting also decreases blood pressure and improves cholesterol levels. LDL cholesterol particle size may increase, which is considered beneficial, and HDL cholesterol count may go up. You could also expect a drop in triglyceride levels.

Inflammation levels can drop as well. Body fat, especially belly fat of visceral fat, increases inflammation. Since intermittent fasting can reduce body fat levels, inflammation levels may fall with it.

Because intermittent fasting improves glucose and insulin function and may help normalize other hormones, it could reduce symptoms of polycystic ovary syndrome. I did not find studies that have proved it out yet, but some researchers speculate this would be the case.

In pregnant women, Ramadan fasting increases HDL Cholesterol (good cholesterol) and decreases hemoglobin A1c, insulin, insulin resistance, blood pressure, and visceral fat.

3. Exercise Performance

As I already mentioned, fasting keeps blood sugar levels steady, and insulin levels low. This is a perfect setup for your body to use maximal fat stores for energy and could be especially helpful for endurance activity.

Endurance athletes are often encouraged to consume carbohydrates on a regular basis, even before and during training sessions, as a way to keep glycogen stores full. Yet, if they just trained in a fasted state consistently, the body would conserve glycogen stores on its own. By consuming carbs around training, they actually prevent their body from becoming better adapted to using fat for fuel.

Not only does intermittent fasting help an athlete use more fat for fuel and conserve glycogen stores, but the fasting has been shown to increase glycogen storage when they do eat.

As exercise intensity increases, you reach a point where you transition from using mainly fat to using less fat and more glycogen for fuel. This point is called your anaerobic threshold.

Fasting raises this threshold, meaning you can train at a higher heart rate while still burning mainly fat.

If an individual can train at a higher intensity while still burning fat, they burn more calories, allowing them to work harder, while still conserving glycogen for even higher intensities.

For speed, power, or strength training, fasted training probably won’t improve performance, but it also will not reduce it. However, if intermittent fasting decreases body fat levels, without negatively affecting strength, speed or power, you actually improve overall performance. You have the same physical abilities, but you can perform them without lugging around as much bodyweight.

When measuring athletes’ performance levels during and outside of Ramadan, athletic performance remained unchanged.

If intermittent fasting is an easy and effective way to manage body fat levels, while continuing to improve physical health, strength, and performance, I think it’s worth experimenting with for a few months.

However, if you’re an athlete who’s peaking for the next Olympic games, or if you’re on steroids, which increases your need for frequent and higher intakes of protein, intermittent fasting might not be for you.

Personally, I’ve found that I can be more liberal with what I eat, without gaining extra body fat, compared to when I regularly ate breakfast.

4. Cognitive Health

Not only might intermittent fasting reduce systemic inflammation, animal studies show that it can also decrease inflammation in damaged brain tissue.

Mice exposed to ischemic stroke were limited to an 8-hour eating window and experienced a reduction in inflammation and tissue damage in the brain.

Interestingly, another study showed that when researchers caused brain damage in mice, the mice who were allowed to eat whenever they wanted to experienced twice the rate of brain cell death as those who ate on an intermittent fasting schedule.

Intermittent fasting appears to also increase the rate of neurogenesis, growth of new brain cells.

Insulin resistance and type 2 diabetes are strongly linked to degenerative brain diseases like Alzheimer’s.

In theory, if intermittent fasting helps to reduce insulin resistance and restore insulin sensitivity, as well as decrease systemic inflammation, it might also decrease the risk of dementia and other cognitive diseases, or at least slow their progression.

Risks of Intermittent Fasting

If I were to write this article as a news story, I’d probably lead with the drawbacks or risks. This stuff tends to get sensationalized.

To be fair in this article, though, I did want to address some of the potential drawbacks. I say “potential” because the issues outlined below were found in the same studies where people experienced all the health benefits above.

So, in my opinion, even if someone experienced some of the changes below, it would be worth it to experience the health benefits above.

Healthy, resistant-trained men experienced a reduction in triiodothyronine (T3), a sign that thyroid hormones dropped. Triiodothyronine is the body’s most powerful regulator of metabolic rate. However, they also lost body fat, suggesting the lower T3 did not cause a reduction in metabolic rate. Perhaps, the fasting just made the men more sensitive to T3, so they needed less.

In a few studies, testosterone levels and IGF-1 also decreased slightly, yet it did not translate into a reduction in lean mass or any other related symptom. It’s possible that the study wasn’t long enough for the body to return to normal levels, or there could be another cause.

Physical performance remained the same or improved as well, which would suggest the slightly lower testosterone and IGF-1 did not cause a problem.

From my own personal experience, I’ve been intermittent fasting regularly for about a year and a half, and when I had my labs checked twice in the past year, my testosterone was over 1200 mg/dL, the highest it’s ever been. And no, that’s not through using anything pharmaceutical; just good nutrition, exercise, lifestyle choices, and supplements.

Another possible drawback of fasting could be a reduction in libido. A small study of men participating in Ramadan fasting showed that they experienced a decline in sexual desire and frequency of sex.

Here’s my assumption about the reduction in libido: After going without food all day, I would assume both the men and women eat more substantial meals in the short window of time between sunset and bedtime. Perhaps they just didn’t feel to frisky with a full stomach.

Why Breakfast Skipping?

By now, you should understand the behaviors and health benefits of intermittent fasting. Perhaps, the idea of eating within an eight-hour window is intriguing to you.

But, why skip breakfast? Why not eat breakfast and lunch, and then skip dinner. You’d still fast for the same length of time, right?

In my opinion, you get two significant benefits from skipping breakfast.

First, you eliminate the chance of eating junk food during one of the most common times for eating it.

Most breakfast foods aren’t that different from the nutrition found in candy bars and potato chips. They are high in sugar and total carbs, moderate-to-high in fat, and low in protein.

Most breakfasts are blood sugar bombs. You drop that breakfast into your digestive system, and it causes a blast in blood sugar, followed by another explosion of insulin. The collateral damage includes a drop in energy levels, an increase in cravings and free radicals, and a shutdown of your ability to burn fat for the rest of the day.

Second, you prolong the period your body uses fat for fuel.

Without food, your blood sugar remains steady, and insulin levels stay low, creating the perfect metabolic environment to release and burn fat.

To tap into your body fat, you need blood sugar and insulin to stay low. Avoiding food for part of your day allows you to do that.

Third, you will very likely improve your productivity.

Your brain thrives on ketones.

When you fast, you produce more ketones for your brain to use, allowing it to function more efficiently. Plus, you don’t have to waste time preparing and eating breakfast. You can just sip on your cup of coffee or tea and get stuff done.

Intermittent Fasting Frequently Asked Questions

I realize I won’t answer all the questions you might have, but here are some of the most common ones.

Please remember: If you have a disease, check with your doctor before making any significant changes to your nutrition or lifestyle. Do not EVER change your medication without doing so with your doctor, even if an article suggests you might be able to do so.

I need to eat before my workout, but I’d like to try intermittent fasting. What can I do?

You do not need to eat before exercise.

You might feel like eating. You might be hungry before your workout. You might have convinced yourself that you need to eat based on misinformation about sports nutrition, but you don’t need to eat unless a doctor requires it of you, or you’re using steroids.

If you use steroids, you assimilate protein and other nutrients at an increased rate. You’d need to eat higher amounts of protein more often to keep up with your body’s demand.

I don’t condone the use of anabolic steroids. I just bring this up because if you use them, and believe intermittent fasting is a bad idea, it might be because you’re viewing the world from your point of view alone.

Again, if you don’t have a disease that requires you to eat, and you’re not using steroids, you don’t need to eat breakfast before exercise.

If you feel like you need to eat breakfast, it’s only because you’ve trained your body to expect it. Give it up for a couple weeks, and you’ll find that you not only survive, but you might even experience better workouts.

Can I drink a protein shake during my fast?

You can drink a protein shake. But then you’re not fasting.

If you believe you’ll “lose muscle” if you don’t get protein in every few hours, let that thought go. It isn’t true.

Can I drink Bulletproof™ Coffee during my fast?

If, by Bulletproof™ Coffee, you black coffee, yes.

If you mean Bulletproof coffee that includes heavy cream and coconut oil or MCT oil, then no. You wouldn’t be fasting anymore.

If you’re following a ketogenic diet, it might be permissible. But that wouldn’t be fasting.

What if I have to eat breakfast sometimes?

One of the things that drives me bonkers about nutrition is how rigid some people and programs can get. I’m embarrassed to admit that I was that way at one time too.

In my opinion, intermittent fasting is a lifestyle, not a diet. Sometimes, other factors in your life interfere with your eating pattern. For example, if we’re in a new city, we might want to eat at the hottest breakfast spot and try something unique. Or, if it’s a special occasion, like National Donut Day, I’ll probably eat some gluten-free donuts from Angel Food Bakery in Minneapolis if given the opportunity.

However, if you fast only when it’s convenient, you’re unlikely to get any benefit.

If you stick with your intermittent fasting program regularly, and eat breakfast with friends once in a while, or indulge in a gluten-free donut (or half dozen), relax. You’ll be back on track the next day.

If I don’t eat every few hours, won’t I lose muscle and slow my metabolic rate?

Every snack food, energy bar, and sports nutrition company would love you to believe this. It is not true.

Some studies have shown metabolic rate increases during a fast for up to 72 hours!

Not everyone would respond that way, but as long as you’re eating sufficient amounts of protein when you do eat, you won’t lose muscle, and you won’t slow your metabolic rate.

Is Intermittent Fasting as Helpful For Women as it is For Men?

There isn’t really a distinction in health benefits between women and men.

However, I do think that women are more prone to stress-related health challenges. Sometimes, the introduction of a new eating pattern can be one more stress that becomes too much.

From my experience working with both men and women, men tend to get faster body composition results from IF. I prefer to have most women stick to a 12-hour window of eating, instead of reducing it to eight hours. But, again, that’s only based on my experience with clients.

Is There Anyone Who Should Avoid Intermittent Fasting?

If you have adrenal fatigue, I’d recommend dealing that before experimenting with intermittent fasting. Also, make sure you’re following a higher-protein diet to support your recovery needs.

Olympic, collegiate, and professional athletes, outside of endurance athletes, probably shouldn’t delve into intermittent fasting either. With the hours they invest in training, and the high levels of energy they burn, they need to eat more often than intermittent fasting would allow.

Physique competitors in the last several weeks leading up to a show would also be better off eating more frequently. Due to their extreme dieting, they can be in highly catabolic state. 

Young adults probably don’t need to think about intermittent fasting either. Our son asked about me intermittent fasting. At the time, he was a 21-year old, healthy, fit young man. My response to him was:

I don’t think it would be that beneficial for you. At your age and with your health, your hormones are primed for making use of protein as often as you eat it. If you wanted to do it as a personal challenge once in a while, that would be fine, but I wouldn’t recommend it more than once a month.

All that said, if you’re a grown adult, or a weekend warrior, who is relatively sedentary outside of workouts, you could benefit from intermittent fasting. I put myself in this group.

One other group that should be cautious is those who have Type 1 or Type 2 Diabetes. If this is you, and you’d like to give intermittent fasting a try, be sure to loop in your doctor so you can manage your blood sugar levels.

I do believe intermittent fasting can be beneficial for those with Type 2 diabetes. You just need to be smart about how you approach it.

Interested in Trying Intermittent Fasting?

I subscribe to the idea of keeping it simple, especially when it comes to nutrition. If you want to give it a try, start with just skipping breakfast.

As time has gone on, I start tweaking things for clients.

For example, I guide people to making their first meal very low in carbs, moderate-to-higher in fat, high in protein, and loaded with non-starchy vegetables. Then, I guide them to a dinner that’s higher in carbs and protein, and lower in fat (but not low fat).

But don’t get hung up on stuff like that though. Just take it a step at a time.

You might be addicted to breakfast right now. Skipping it will be enough of a challenge of its own that you don’t need to worry about anything else.

If you’re still not convinced to give intermittent fasting a try, and you’re hellbent on eating breakfast, do your body a favor: Get rid of the carb-rich junk—cereal, toast, pancakes, waffles, fruit juice, etc.

Eat a higher-protein, low-carb breakfast instead, like meat and nuts, an omelet, or a low-carb protein shake.

Just don’t knock the intermittent fasting unless you’ve really tried it.


Keep the conversation going.

Leave a comment, ask a question, or see what others are talking about in the Life Time Health Facebook group.

The Life Time Health Team

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