The alarm rings and you press “snooze” one time too many. By the time you roll out of bed, you think it’s too late for breakfast. Estimates vary, but around 25% of the population skips breakfast on a regular basis (Cho et al. 2003). The potential perils can include a more sluggish metabolism as the body shifts into starvation-response mode. And coupled with a tendency to become ravenous and binge later: weight gain. Cognitive abilities can also suffer: you may get headaches, feel fatigued and be less able to concentrate.
Yet plenty of people bypass breakfast and don’t seem to suffer. Many—perhaps your clients—say they aren’t hungry. And some even rev up by working out without fueling first in the belief that they’ll burn more fat that way.
So what’s the truth? Is skipping breakfast harmful, or have the dangers been overhyped?
Some studies have shown that breakfast-skippers, including kids and adolescents, are more likely to be overweight or obese (Cho et al. 2003). But most of these studies are only observational, so it’s hard to know for sure. Researchers look for patterns in a snapshot of data gathered from people at one point in time, or over several years: Are certain eating behaviors more likely to be associated with specific outcomes, like how much people weigh?
Even if associations are identified, this type of research isn’t foolproof. Often it relies on self-reporting, and some people portray a rosier picture of their habits than is accurate. Plus, a different habit could be responsible. If breakfast-skippers also did little exercise and activity was not accounted for, it might be that people who don’t exercise are more likely to gain weight, regardless of whether or not they eat breakfast. Only a well-designed experimental trial can show that something causes something else, and few long-term experimental trials have studied eating breakfast.
“This kind of data is very hard to collect,” says Melinda Manore, PhD, RD, nutrition professor at Oregon State University, Corvallis, and author of several textbooks, including Nutrition for Life (Benjamin Cummings 2006). Ideally, you would need to follow a large number of people—one group who ate breakfast and one group who didn’t. Since weight is gained gradually, a study must last for years to properly assess an effect. As with exercise studies, it’s tough to ensure that people stick to the program. And efforts must be made to make sure the nonbreakfast eaters don’t start eating and that the breakfast eaters don’t start skipping. Enough people need to be enrolled to make up for dropouts, and subjects need to be discouraged from dieting or overeating—both of which could influence the results.
So far, no major study has done this. That is why the 2010 Dietary Guidelines committee concluded there is inconsistent evidence that adults who miss a morning meal are upping their chances of becoming overweight or obese (Dietary Guidelines Advisory Committee 2010). It might be true that skipping breakfast leads to weight gain, but there are not enough studies to prove it.
Even if there is an increased risk, that’s no guarantee that you will put on weight, since weight gain also depends on how much you eat all day. “To assess the power of breakfast, you have to look at overall eating patterns,” says Enette Larson-Meyer, PhD, RD, FACSM, nutrition professor at the University of Wyoming and author of Vegetarian Sports Nutrition (Human Kinetics 2007). “It’s hard to argue that someone at a healthy body weight with an overall healthy eating pattern of nutritious foods spaced out throughout the day should be forced to eat when they don’t feel hungry first thing in the morning.
“On the other hand, not eating may provoke unhealthy eating patterns,” she explains. “A person might get so hungry later that they start craving chocolate and chips and end up overeating because they started the day with too little energy.”
Some people opt to skip food and go for coffee to rev up lagging energy levels. But this doesn’t change the physiological need for calories, and it may lead to more extreme hunger later—and to overeating. Most people perform better, mentally and physically, when they have eaten breakfast—especially if they are physically active. “In the few studies conducted in athletes, lack of food prior to exercise decreases performance. That’s why the recommendation is to consume some food and/or beverages prior to exercise,” says Marie Dunford, PhD, RD, author of the textbook Nutrition for Sport and Exercise (Cengage Learning 2007). “Of course, the intensity and duration of the workout must be considered when deciding how much and when to eat.”
What many people fail to consider is that the body awakes in an energy-deprived state. Depending upon when dinner or the last evening snack was consumed, a person may have gone 10–15 hours without food. Normally, the body gets energy from fat and carbohydrates. Glucose, or sugar from carbohydrates, is needed to metabolize fat and is the exclusive fuel source for the brain and red blood cells. The liver’s stored glycogen supplies the body with glucose throughout the night. “When you wake up, blood sugar may be low and the liver may be running low in glycogen,” says Larson-Meyer. “This limits the glucose that is available for the energy needs of the brain and body.”
Though some have demonized sugar and other carbs, Larson-Meyer says, “You do need glucose for brain function and—if you exercise in the morning—as a substrate for muscles so that you can get an intense workout in and recover well afterward. Studies in children have shown that a little sugar helps them think better and not be so sluggish.”
Breakfast not only provides readily available calories for morning activity (Marangoni et al. 2009); it is also integral to obtaining essential nutrients. Protein is needed for muscle building and repair, as well as for other functions, including maintenance of hormones and enzymes.
“Most people get plenty of protein each day but tend to consume it later in the day,” Manore says. “New research is showing that it is better absorbed and utilized if intake is spread throughout the day.” One reason why the body doesn’t function optimally on one meal a day is that the body usually doesn’t absorb 100% of a nutrient when it is consumed. So eating several meals can help the body use more of the nutrients it gets from food.
Protein is a blanket term for the many types of amino acids found in foods. “When you eat a lot of protein at one time, there may be excess amino acids that are not needed to replenish the body’s pool. There is nowhere to store them, so they are converted to nitrogen and lost through urine,” Manore says. “Spreading smaller amounts out to constantly give muscles and the body protein throughout the day can not only help maintain lean muscle mass but also help it to function better.”
Additionally, breakfast can ensure an adequate day’s supply of fiber, as well as vitamins, minerals and other micronutrients. “It’s an important way to kick-start your day and start taking in the nutrients you need,” Larson-Meyer says.
Some people assume that not feeling hungry is an intuitive signal not to eat. “Just because you don’t feel hungry doesn’t mean that you don’t need calories. It might mean you need them more than you think,” says Larson-Meyer. Diminished appetite is thought to be a protective adaptation when the body is having a starvation response. One theory is that this is an evolutionary adaptation: while experiencing a huge energy deficit, the body can conserve energy if it doesn’t react by getting famished, which would drive up the energy used to look for food when none was available.
Dan Benardot, PhD, RD, FACSM, professor and head of nutrition at Georgia State University, Atlanta, has studied how large energy deficits, such as those that can be created by skipping breakfast, affect athletes. In his book Advanced Sports Nutrition (Human Kinetics 2005), he explains that even if body weight stays stable because a person doesn’t eat more calories over the whole day, an athlete may have less lean body mass and higher body fat levels as a result. Both the low blood sugar in the long periods of not eating and the overly large meals that follow can lead to surges of excess insulin, an effect that encourages extra body fat. Benardot’s online food log helps track hourly energy fluctuations (http://nutritiming.com) to show when and how much to eat to maintain good energy balance.
Even if hunger diminishes once you start working out, if your fuel tank is on empty and you rev up the engine, your body will demand more fuel in the form of glucose and fatty acids from the blood. If more fuel is not available, the body will break down muscle proteins. What’s more, by driving your body into an even deeper energy deficit, you’ll be more likely to get famished and binge later.
And if you think you’ll burn more body fat exercising on an empty stomach, think again. If the body burns a higher percentage of fat while exercising on no breakfast in the morning (and study results are mixed), that doesn’t mean metabolism—or total calorie burn—is speeding up. “If you’re going to do a long or strenuous workout on an empty stomach, you may not have adequate carbs to power your workout and so you won’t be able to work out as long or as hard,” Larson-Meyer says. “Even if you are burning a slightly higher ratio of fat, with impaired performance you may not be burning as many total calories or total calories of fat as you could if you were well-fueled.”
Some studies have suggested that there is an increase in fat loss. “But if you measure the amount of fat that’s burned, it’s a miniscule amount,” Manore says. And there’s little evidence that it results in long-term weight loss. A recent study in the International Journal of Sport Nutrition and Exercise Metabolism measured men who used the treadmill at a moderate intensity for around 35 minutes both before and after eating breakfast. Those who ate first burned significantly more calories and burned a significantly higher percentage of fat 12 and 24 hours after the workout, compared with those who worked out without eating. There appeared to be an enhanced utilization of fat when exercising after eating (Paoli et al. 2011).
Does a black coffee with 1 teaspoon of sugar (15 calories) count? What about a 50-calorie apple? Is a doughnut okay? Is eating at 10:00 am as nourishing as eating at 7:00 am?
Breakfast means literally breaking the food fast that has occurred since the last evening meal. But how many calories are needed to qualify as “breakfast” and exactly when they are required are debatable questions. “There is no standardized definition,” Manore admits. Some studies measure breakfast as an absolute calorie amount. Others quantify it by describing the percentage of breakfast calories compared to the total day’s intake.
“Usually we aim for breakfast providing 25%–30% of the calories for the day, so the amount will depend on a person’s daily energy expenditure,” says Larson-Meyer. A highly active female who eats 2,500 or more calories per day might have a breakfast of at least 600 calories, and an active male might have more. A lower-calorie breakfast, such as a few egg whites or a piece of fruit, might suffice, but more energy may be needed sooner, especially if a workout is imminent.
Ideally, the morning meal should provide carbohydrates and fiber from fruits, vegetables and/or beans, as well as protein from low-fat milk or yogurt, eggs or plant sources such as nuts, beans and whole grains.
While fruit is generally recommended over juice because fruit contains more fiber and fewer calories, a lean exerciser need not fear juice. “Most people should avoid drinking their calories, but if juice is an easy energy source before your workout in the morning, go ahead and drink it,” Larson-Meyer says.
As for a doughnut, Sunday-morning pancakes or the omnipresent pastries at breakfast work events, they may be acceptable under certain circumstances.
“Something is better than nothing, and if you’re in the woods starving, a doughnut is okay,” Manore says. But keeping a stash of easy breakfast backups, like breakfast bars, nuts or even cold leftovers, can give you more nutritious choices and save you from filling up on empty calories. You can also enhance no-no foods. “Make whole-grain pancakes, or eat fruit with your doughnut,” Manore advises. Don’t be afraid to get creative: some cultures eat soups for breakfast, others eat beans (on toast or in bean burritos). Aim for a breakfast that provides energy and nutrients and that helps you feel satiated.
Cho, S., et al. 2003. The effect of breakfast type on total daily energy intake and body mass index: Results from the third national health and nutrition examination survey (NHANESIII). Journal of the American College of Nutrition, 22 (4), 296–302.
Dietary Guidelines Advisory Committee. 2010. Dietary Guidelines for Americans. Nutrition Evidence Library: What is the relationship between breakfast and body weight? www.nutritionevidencelibrary.com/conclusion.cfm?conclusion_statement_id=250318; retrieved Feb. 7, 2011.
Dunford, M., & Doyle, J.A. 2008. Nutrition for Sport and Exercise. Belmont, CA: Thomson Wadworth.
Larson-Meyer, D.E. 2007. Vegetarian Sports Nutrition. Champaign, IL: Human Kinetics.
Marangoni, F., et al. 2009. A consensus document on the role of breakfast in the attainment and maintenance of health and wellness. Acta Biomedica, 80, 166–71.
Paoli, A., et al. 2011. Exercising fasting or fed to enhance fat loss? Influence of food intake on respiratory ratio and excess postexercise oxygen consumption after a bout of endurance training. International Journal of Sport Nutrition and Exercise Metabolism, 21, 48–54.
Thomson, J. & Manore, M. 2006. Nutrition for Life. San Francisco: Benjamin Cummings.