To eat or not to eat?: A scientific review article on the benefits of breakfast

Introduction

It is a well-known idea that breakfast is considered the most important meal of the day in most cultures. This is thought to be because it is the first meal after a night of fasting while asleep. This idea makes sense and is generally accepted but is there any real consequences if you did not eat breakfast and how much of an impact does this really have on a person’s life.

As of today, over 1/3 of American adults are classified as obese.1 Obesity is currently the number one chronic disease but it does not just stop there. Obesity can lead to other diseases like heart disease, stroke, cancer, and diabetes. Most of these diseases could be preventable if obesity was the cause. The tolls that these diseases have on a person’s life are monumental and they all could be stopped if the problem of obesity was stopped. Another issue with the rising numbers of obese individuals is the increased health care costs in our country. It is estimated that the costs of caring for obesity and obesity related diseases is about $147-210 billion per year in the United States.

The rising obesity trends in the United States are shown above. It is clear that since 1986, the percent of adults that are obese has more than doubled. Not only is obesity becoming more widespread all over the country, but it is becoming more common as well. When looking at the statistics for children, 1 in 3 children are considered either overweight or obese. This is even more concerning because the children will then grow up to be obese and most likely raise obese children. Not only that but having this increased weight can lead to known physical and psychological effects on the child. Some of these effects could be metabolic syndrome, low self-esteem, depression and anxiety. Therefore, the problem of childhood obesity is much more than just a weight issue.

The measure of a persons Body Mass Index (BMI) is calculating using their height (m) and weight (kg). It is a common tool used to assess the weight status of people because it is so easy to calculate and compare to other people. A person is considered obese if their BMI is greater than or equal to 30. In this literature review, comparing the BMIs of individuals was used as a way to measure obesity.

At the same time that obesity rates have been rising, the number of people who always consume breakfast has been declining. The number of adult Americans who skip breakfast has more than double in the past 30 years and continues to rise. Nowadays, people skip breakfast for many reasons whether that be that they are not hungry right when the wake up, they do not have enough time in the morning to prepare a breakfast, or they are trying to watch their weight so they skip the calories from breakfast.

After reviewing the literature on this topic, it was apparent that a majority of the studies used children as their subjects. One reason for this is because it is very easy to get kids to participate in studies through schools. Secondly, this topic relating to kids spikes the interest of a lot of people because they think that if they can stop obesity at a younger age, it will not be as much of a problem when they are adults. It has even been shown that children who consume breakfast regularly have improved cognitive function and academic performance. Lastly, children who consume breakfast are more likely to meet the recommended requirements of vitamins and minerals as well as have more positive health outcomes than children who do not eat breakfast. Therefore, it would make sense to teach healthy habits at a younger age to raise healthy kids that can grow up to raise their own healthy children.

Since the obesity rates have been consistently rising and the number of people eating breakfast is falling, there should be a correlation between the two. This could be due to the fact that if you eat breakfast at the beginning of the day, then you will not be as hungry throughout the day and will eat smaller portions of food. It could also be due to the fact that eating breakfast supplies enough energy to engage in physical activity to perform normal activities of daily living as oppose to being sedentary. My hypothesis was that people who eat breakfast regularly have a lower BMI compared to people who do not eat breakfast regularly.

Review of Research Studies

Cho, S. (2013). The Effect of Breakfast Type on Total Daily Energy Intake and Body Mass Index. Journal of the American College of Nutrition, 296-30.(6)

The main objective of this study was to find a relationship between breakfast intake and BMI. They were interested in this topic due to the rising obesity rates and the major threat that has to public health. The hypothesis was that breakfast consumption itself is associated with BMI and that the type of food eaten at breakfast affects BMI.

For the methods, the study utilized the National Health and Nutrition Examination Survey (NHANES II) to look at the dietary and nutritional behaviors of United States citizens. The food intake of the participants was based off of a 24-hour dietary recall as well as dietary questions from the survey. For this study, breakfast was defined as, “any food or beverage consumed in a meal occasion named by the respondent as breakfast.” This means that is the participant did not call their food breakfast then they were considered to be someone who skipped breakfast for survey purposes. Also, this study did split breakfast into different categories such as dairy, meat and eggs, fruits and vegetables, ready to eat cereal and breads. Individuals were then put into categories based on their responses or classified as a breakfast skipper if they indicated that they did not consume breakfast. Trained researchers who traveled year round in mobile examination centers measuring the participant’s anthropometrics calculated the BMI for these individuals. When using the ANOVA and linear regression model to analyze the data, the researchers did take into account gender, race, age and the poverty index to result in the most accurate conclusions.

Forty thousand subjects were chosen randomly but the final number of subjects ended up being 16,452. This is because they excluded participants that were under 18, due to the fact that they are not done growing and their BMI measurement might be thrown off by an inaccurate height or weight measurement. Pregnant women were also excluded considering that their weights would be higher than normal and throw off the BMI values. The participants were 53% female and 47% male.

When looking at the results above, some points stand out. The people were split into either someone who did not consume breakfast (breakfast skipper) or someone who ate breakfast and their meal was categorized based on the composition of the meal. The average BMI of the people who skipped breakfast was 26.92. This number is higher than some of the people who ate breakfast such as in the categories of Fats and Sweets, Fruits and Vegetables, Ready-to-eat cereal, cooked cereal, breads, quick breads and beverages. This table shows that even though the BMI of people who skip breakfast is not that much higher compared to people who eat breakfast, it still is ultimately higher than most of the categories of breakfast eaters.

The results above show the average outcomes in the study to put the data in perspective. This table confirms that people who eat breakfast have a lower BMI averaged at 26.31 when compared to the people who skip breakfast at 26.92, being a significant difference. Again, the BMI is not that much higher but it still is higher compared to the people who eat breakfast. The study also stated that while it was not fully understood why this was the outcome, it was found to be a pattern that people who reportedly regulated and planned out their meals throughout the day did have a lower BMI so this factor could contribute to the results. All in all, this study did conclude that consuming breakfast leads to a lower BMI.

One very strong point of this study was the high number of participants. Having a random pool of 16,452 subjects allows for great diversity and the coverage for a wide range of people in a study. Another pro was that this study accurately measured the BMI of the participants. The use of trained professionals taking these measurements allows for little error in the results. However, a major con of this study is the use of a 24-hour dietary recall and a survey. These methods could not be very indicative of someone’s everyday eating habits and could have been answered differently on a different day.

Timlin, M. (2008). Breakfast Eating and Weight Change in a 5-Year Prospective Analysis of Adolescents: Project EAT. Pediatrics, 638-645.(9)

This studies purpose was to investigate a possible reason for the obesity rates increasing alarmingly fast in the United States. They pointed out that the presence of overweight adolescents has doubled and has tripled in adults in just the past 20 years. The study also pointed out how 12-34% of adolescents regularly skip breakfast and this percent is shown to only increase as they age. It was proposed that regular breakfast consumption would lead to controlling a child’s appetite thus stabilizing the energy intake in relation to body weight regulation and having a stable BMI. The purpose of this study was to examine the association between breakfast frequency and body weight over a 5 year body weight change in adolescents. The hypothesis was that breakfast frequency would have an inverse association with body weight and increased body weight over the 5-year span.

This study used 4,646 public middle and high school students from Minnesota. The subjects were chosen randomly and the study made sure to include a diverse group of socioeconomic and ethnic backgrounds. The instrument used to collect data on food habits was a 221 item self-reported survey. This survey was developed by research staff who held focus groups, extensively reviewed literature and talked to youth to make a relevant survey to use. This survey was taken by the students to assess socioenvironmental factors, personal factors, behavioral factors and dietary patterns. The dietary intake was also assessed using a 149 question Youth Adolescent Food Frequency Questionnaire. The height and weight was taken during the school year by trained research staff to calculate the BMI of the children. Five years later, a survey was sent out to the participants as a longitudinal follow up to see the changes in eating patterns and weight status. The total sample size ended up being 2,216 due to the people who did not respond. The BMI this time was measured from a self-reported height and weight.

A statistical analysis was used to assess the data. The breakfast frequency was recorded in 3 categories: breakfast eater, irregular eaters or daily skippers. The dependent variable was the second BMI follow up measurement. One of the sample breakfast frequency questions was, “During the past week, how many days did you eat breakfast?” and the answer choices were never, 1-2 days, 3-4 days, 5-6 days or every day. If the participants did not answer this question, then they were excluded from the study.

The results are shown above. Time 1 is the measurements and information taken at the beginning of the study and Time 2 is the information from after the 5 years. The different models are if you factored in different variables such as poverty, socioeconomic status and behavioral factors. It is evident that people who reportedly consume breakfast daily have a BMI lower than the people who never eat breakfast (21.7 vs. 23.4). This is true for all of the models factoring in different variables. This is also true for the data taken after 5 years. The breakfast eaters still have a lower BMI of 23.4 compared to the skippers while a BMI of 24.6. The BMI measurements did increase for all categories after 5 years but this is because the participants were children so they all were going to grow over 5 years.

The results shown above indicated the change in BMI over the 5-year study in relation to the breakfast frequency of the participants. Again, the three different models are factoring in different variables that could affect the results. It is clear that daily breakfast consumers have the lowest BMI change over the five years. The average increase of BMI for them was 1.6 compared to the people who never ate breakfast whose BMI increase by 2.2. This shows that even over time, breakfast consumption leads to a lower BMI compared to people who skip breakfast and have a large weight gain over 5 years.

One very strong point of this study was that it spanned 5 years. This is very beneficial to the results because it takes into account the behavior change and how that has a long-term effect on weight status. Secondly, this study considered different variables that might affect the results such as poverty index, environmental and personal factors. When factoring all of these in, the results still showed true to prove their hypothesis, showing strong data and results. Lastly, this study utilized a diverse group to really assess the impact of consuming breakfast on all types of people. One con of this study was having the participants self report their BMI the second time. This could skew the results because someone might not know their exact height or weight, which could mess up the data. Another con is the use of surveys for gathering information about the participants. This method is very situational because the participants answers that specific day may have been different if the survey was taken another day and under different circumstances.

Nelson, H. (2011). Breakfast Frequency Inversely Associated with BMI and Body Fatness in Hong Kong Chinese Children Aged 9-18 Years. British Journal of Nutrition, 106, 742-751. (10)

This last study was also concerned with the increasing rates of obesity and the many recent studies of breakfast frequency being related to BMI. The purpose of this study was to evaluate their relationships with self-reported breakfast frequency and food consumption behaviors in a large representative population sample of Hong Kong Chinese children aged 9 – 18 years. There were 11,570 participants with a approximately equal distribution of age and sex. The study used data from the Department of Education in Hong Kong to compile a sample frame from all of the schools in order to get a wide range of participants.

The anthropometric measurements to calculate the BMI were taken by eight research staff who used standardized instruments. They took the weight without shoes and measured the weight twice for accuracy. The participants of the study completed a self-administered dietary behavior questionnaire called the Rapid Dietary Behavior Assessment. This survey looked at daily and weekly diet behaviors as well as compared the results to a 24-hour recall of their nutrient intake. One sample question about the breakfast consumption was, “How many days over the past week did you have breakfast?” and the students were categorized into either skippers (0-2 times/week), semi-skippers (3-4 times) or non skippers (5-7 times). An ANOVA and linear regression model was used to compare the results with BMI as the dependent variable and breakfast frequency as the independent variable. The study did include age, sex and exercise frequency as potential confounding variables in the data.

The results shown above represent the data from the middle school children. The numbers on the y-axis show the different percentiles of BMI. It is clear that for both males and females, the ‘skippers’ of breakfast have a BMI in the higher percentile than compared to the non-skippers of breakfast who are in the lower percentiles for their BMI. This means that people who eat breakfast have a lower BMI compared to people who do not eat breakfast.

The results above show the data from the high school children. Again, the numbers on the y-axis represent the percentiles of BMI. From these results, it is clear that for both male and female the people who skip breakfast have a higher BMI compared to the people who consume breakfast.

One very strong point of this study was the high number of participants. Having 11,570 students, chosen randomly from a diverse population allows the results to be representative of a wider population of people. Secondly, trained professionals with standardized equipment very accurately measured the BMI to ensure the correct data was obtained. One con of this study was the use of a questionnaire and dietary recall. These methods are not indicative of everyday eating patterns and could be answered erroneously based on the student’s desire to answer completely accurate. Lastly, even though BMI was measured so accurately, it is not the based way to assess weight status. Since the participants were children, the BMI could be skewed since the children are still growing and not at their final height and weight.

Conclusion

In conclusion, all three of these studies were in support of my hypothesis that people who eat breakfast regularly have a lower BMI compared to people who do not eat breakfast regularly. All of the results showed that both adults and children who eat breakfast regularly have a lower BMI compared to people who skip breakfast. However, the difference in the BMI was not that significant, meaning that if you skip breakfast it does not necessarily mean that you will be overweight or unhealthy. Therefore, more research is needed on the topic to identify why these were the results and how much of an impact eating breakfast really has.

Future Research

There are many ideas that could be based off of this topic for future research. First, looking at the effect that different breakfast compositions have on weight status would be beneficial to the public. Evaluating which type of breakfast whether a carbohydrate based, protein based, fruit and vegetable breakfast or a mixed breakfast is the best for you would be helpful to know. This would allow people to gear their diet choices to what makes the most sense for their body. Secondly, using another way to assess dietary behavior other than a 24-hour recall or survey would be valuable. If studies were conducted over a longer period of time with accurate food records would help to really see the food behaviors of people and how this affects their weight status. Next, it would be interesting to see the affect of breakfast consumption with a wider range of the population. This could be testing the affects of breakfast on not only children but adults and the elderly so health professionals could back up their recommendations with sound evidence. Lastly, the use of more precise measurements to assess weight status would be beneficial. Studies could utilize multiple measurements like BMI in combination with Ideal Body Weight (IBW) and other tools like a Bod Pod to acquire a more accurate weight status of someone to compare to other people. All in all, this topic is becoming more and more popular due to the rising rates of obesity and should continue to be researched to find the most accurate information to help the general public.

References:

1. CDC. (2016). Adult Obesity Facts. 2016, from https://www.cdc.gov/obesity/data/adult.html CDC. (2016). Adult Obesity Facts. 2016, from https://www.cdc.gov/obesity/data/adult.html

2. Kapantais, E. (2009). Breakfast Skipping and its Relation to BMI and Health-Compromising Behaviors. Public Health Nutrition, 14, 101-108.

3. Cawley J and Meyerhoefer C. The Medical Care Costs of Obesity: An Instrumental Variables Approach. Journal of Health Economics, 31(1): 219-230, 2012; And Finkelstein, Trogdon, Cohen, et al. Annual Medical Spending Attributable to Obesity. Health Affairs, 2009.

4. Watch, P. H. (2015). Weight of the Nation. from https://publichealthwatch.wordpress.com/2015/09/23/weight-of-the-nation-a-look-at-the-most-and-least-obese-states-in-america/

5. Amigo-Vasquez, I. (2016). Skipping Breakfast, Sedentarism and Overweight in Children Psychology, Health and Medicine, 21, 819-826.

6. Cho, S. (2013). The Effect of Breakfast Type on Total Daily Energy Intake and Body Mass Index. Journal of the American College of Nutrition, 296-301.

7. Coppinger, T. (2011). Body Mass, Frequency of Eating and Breakfast Consumption in 9-13 year olds. Journal of Human Nutrition and Dietetics, 43-49.

8. Barton, B. (2005). The Relationship of Breakfast and Cereal Consumption to Nutrient Intake and Body Mass Index. Journal of the American Dietetic Association, 1383-1389.

9. Timlin, M. (2008). Breakfast Eating and Weight Change in a 5-Year Prospective Analysis of Adolescents: Project EAT. Pediatrics, 638-645.

10. Nelson, H. (2011). Breakfast Frequency Inversely Associated with BMI and Body Fatness in Hong Kong Chinese Children Aged 9-18 Years. British Journal of Nutrition, 106, 742-751.