Breakfast is Not The Most important Meal of the Day: Feel Free to Skip it

It always irritates me when a friend tells me that I should eat breakfast because it is “the most important meal of the day”. Many in the nutritional mainstream have propagated this concept along with the idea that skipping breakfast contributes to obesity. The mechanism proposed seems to be that when you skip breakfast you end up over eating later in the day because you are hungrier.
The skeptical cardiologist is puzzled. Why would i eat breakfast if I am not hungry in order to lose weight? What constitutes breakfast? Is it the first meal you eat after sleeping? If so, wouldn’t any meal eaten after sleeping qualify even it is eaten in the afternoon? Is eating a donut first thing in the morning really healthier than eating nothing? Why would your first meal be more important than the last? isn’t it the content of what we eat that is important more than the timing?
The 2010 dietary guidelines state

eat a nutrient-dense breakfast. Not eating breakfast has been associated with excess body weight, especially among children and adolescents. Consuming breakfast also has been associated with weight loss and weight loss maintenance, as well as improved nutrient intake

The US Surgeon General website advises that we encourage kids to eat only when they are hungry but also states

Eating a healthy breakfast is a good way to start the day and may be important in achieving and maintaining a healthy weight

A recent study anayzes the data in support of the “proposed effect of breakfast on obesity” (PEBO) and found them lacking.
This is a fascinating paper that analyzes how scientific studies which are inconclusive can be subsequently distorted or spun by biased researchers to support their positions. It has relevance to how we should view all observational studies.
Observational studies abound in the world of nutritional research. The early studies by Ancel Keys establishing a relationship between fat consumption and heart disease are a classic example. These studies cannot establish causality. For example, we know that countries that consume large amounts of chocolate per capita have large numbers of Nobel Prize winners per capitaChocolate Consumption and Nobel Laureates
Common sense tells us that it is not the chocolate consumption causing the Nobel prizes or vice versa but likely some other factor or factors that is not measured.
Most of the studies on PEBO are observational studies and the few, small prospective randomized studies don’t clearly support the hypothesis.
Could the emphasis on eating breakfast come from the “breakfast food industry”?
I’m sure General Mills and Kellogg’s would sell a lot less of their highly-processed, sugar-laden breakfast cereals if people didn’t think that breakfast was the most important meal of the day.
My advice to overweight or obese patients:
Eat when you’re hungry. Skip breakfast if you want.
If you want to eat breakfast, feel free to eat eggs or full-fat dairy (including butter)
These foods are nutrient-dense and do not increase your risk of heart disease, even if you have high cholesterol.
You will be less hungry and can eat less throughout the day than if you were eating sugar-laden, highly processed food-like substances.
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