I've grown accustomed to sensational news headlines on health which convert flawed scientific studies into catchy one-liners like “Red meat increases cancer” or in this case “Skipping breakfast increases heart attack risk.” Before we discuss the actual study on breakfast and its findings, I want to do a quick refresher on why such observational studies continue to mislead the public into making poorly informed health choices.
Healthy User Bias (“HUB”)
One critical concept to understand that explains why most observational studies are flawed is called the “healthy user bias” or some call it the “healthy user effect.” To simplify things, let's refer to healthy user bias with the acronym “hub.” Hub essentially means that individuals who engage in one healthy behavior are likely to behave in multiple other ones so that the results of the study can't really differentiate which health behavior leads to a specific outcome. A few examples are as follows:
1. Vegetarian Diets and Red Meat: A typical Western vegetarian is likely to be more health conscious and engage in other healthy behaviors like exercise. I underline “Western” here since this is not the case with Indian vegetarians who in most cases are vegetarian for religious, rather than health reasons and in my clinical experience tend to consume far less vegetables and nutrient-dense foods than their Western vegetarian counterparts.
Many studies on red meat that show adverse health events are influenced by hub. The average American red meat consumer is typically eating fast food or processed meats alongside other unhealthy foods like sodas and fries. He or she may be more likely to smoke, eat less vegetables, and also be more sedentary.
When studies claim “red meat raises the risk of cancer, heart disease and/or overall death,” often these studies fail to completely extract out all of the potential unhealthy variables intrinsic to the average red meat eater. These studies also fail to focus on the healthier meat eaters who eat high quality meats in moderation accompanied by abundant plant-based foods, while exercising and prioritizing sleep and stress management. I blogged on the red meat-cancer connection here and discuss red meat in more detail here.
2. Multivitamins: Individuals consuming multivitamins also tend to be health focused and may engage in other behaviors like eating healthier foods, exercising and drinking more water. Multivitamins are also typically consumed by individuals who are in a higher socioeconomic bracket, which alone increases overall health and lifespan since they tend to have health insurance and engage in other forms of preventative health practices (vaccines, screening tests, etc.).
Studies will do their best to account for these variables which are referred to as “confounders,” but it is impossible to completely remove their impact from study findings. Multivitamin studies that have removed most of these confounders have found there to be no health benefit for the average consumer. I'm not including individuals with known deficiencies or digestive disorders that impair nutrient absorption.
Back to Breakfast Skipping
So now that you understand hub, let's return to the study on skipping breakfast. For decades we have been given the following pieces of advice about breakfast:
- “Breakfast is the most important meal of the day”
- “Skipping breakfast slows down your metabolism and makes you store fat”
- “Skipping breakfast keeps you hungry all day and leads to overeating”
- “Breakfast gives you energy and skipping it leads to fatigue”……etc.
Since these messages have been further bolstered and promoted by pervasive campaigns from the multi-billion dollar breakfast food industry, most health conscious individuals do truly believe that breakfast is essential fuel to help them burn body fat and prevent hunger throughout the day.
If this is the case, then why do obesity and diabetes numbers continue to skyrocket around the world? Clearly breakfast is not the panacea it has been reputed to be.
Now based on what you've learned about hub, I want you to quickly read over this popular article from the Telegraph about the breakfast study, because most laypeople are not reading the actual research studies to form conclusions about lifestyle habits. They instead read headlines and study summaries from popular websites like the Telegraph, Yahoo News, Huffington Post, etc. The Telegraph article on breakfast puts in boldface red the following quote from a UCSF physician:
“That breakfast is the most important meal of the day has been proven right in light of this evidence.”
I was shocked to see the word “proven” in this quote. Anyone familiar with observational studies (or any study for that matter) knows that it is impossible to “prove” anything due to the multiple confounders we discussed. In this same article, the author reports the following:
“Researchers also said those who skipped the first meal of the day were also more likely to have an unhealthier lifestyle overall.”
What?? Basically the researchers themselves admitted that their study fell victim to the all powerful hub, yet the headlines from every major news channel transmitted the message and overall impression that skipping breakfast increases heart disease risk, further supported by the definitive quote provided by a UCSF physician.
The Truth About Breakfast
So what's the real story on breakfast? Should you eat it, should you skip it, or how about a combination of both? In our clinical practice where we almost exclusively treat patients with some combination of obesity, diabetes, cholesterol problems, and impending or existing heart disease, we have often found that skipping breakfast is one of the most powerful interventions to help individuals reverse disease risk.
How can I possibly advise a diabetic with an elevated morning fasting blood glucose to regularly eat a bowl of whole grain cereal or a slice of wheat toast, which will take an already abnormal glucose level and make it worse? On the other hand, what about one of my patients who is an elite athlete with no signs of insulin resistance or other health risks who has been eating a healthy breakfast for years with no problems? No need for me to push for breakfast skipping in this case.
As with everything else in life, context is all important. Nutrition advice must be personalized to the individual and by the way, context can change. I've had the pleasure of transforming sedentary diabetics for whom their typical “healthy breakfast” was toxic, to non-diabetic amateur athletes who could now enjoy breakfast every now and then with no problems at all.
In my early days, I too noticed that my typical patient who skipped breakfast was someone who usually went to bed late, rushed out the door to get to work, often skipped lunch, and then came home famished….succumbing to intense snacking behavior and an over-sized dinner usually eaten late at night.
“Skipping breakfast” in these patients was a surrogate marker for a fast-paced, high stress lifestyle, especially here in bustling Silicon Valley, where eating healthy meals is not always a priority. Neither were earlier bedtimes, exercise or stress management practices. To conclude that the act of breakfast skipping was one of the root causes for heart disease risk makes no sense. It was a mere byproduct of an unhealthy, accelerated modern day lifestyle.
As you can tell, I'm a bit frustrated at this latest headline. Why? Well coming back to our clinical experience, we have noticed that “skipping breakfast” in the form of intermittent fasting can rapidly improve blood glucose, lower excess fat-storing insulin levels, drop dangerous triglyceride levels, and improve body composition better than most other lifestyle interventions.
Skipping breakfast is a potentially powerful therapeutic intervention that can be highly effective when used in the right patients. Patients typically report increased energy levels, even during their intense workouts, and they also love the convenience of having to prepare one less meal. They are liberated from the constant sensation of hunger and their dependence on frequent eating intervals.
The next time you come across a sensational news headline claiming that a specific nutrient or practice is unhealthy or healthy, be sure to scrutinize it for hub and also use your own intuition and wisdom. If you feel better and your numbers look better, then question whether a study's conclusions are applicable to your own case.
I also encourage you to wait for all the initial news “buzz” to die down and then read critiques from other experts, find more established scientific resources that comment on the study, and consider reading the study yourself. You'll quickly become an expert at identifying hub and other potential confounders that influence study results. Don't let a sensational news headline interfere in your pursuit to find foods, routines and behaviors that can dramatically improve your health.