Skipping breakfast has pretty consistently been linked to health risks – high blood pressure, overweight, and an unhealthy assortment of blood-fats, among them. But what’s interesting is that the health effects of skipping breakfast – even being overweight – don’t seem to be the result of indulging in extra “make-up” meals throughout the day. So it’s not about just the calories: There seems to be something else at play. The short answer may be that skipping the early meal keeps your body in the stressful state of fasting for longer, which can disrupt your metabolism in considerable and, apparently, life-threatening, ways.
The new study out of Harvard looked at the health records of nearly 27,000 men, all healthcare professionals 45-82 years old when the study began. The team looked for correlations in lifestyle choices – e.g., skipping breakfast – and health outcomes over a period of about 16 years.
Men who skipped breakfast were 27% more likely to experience heart attack or to die as the result of coronary heart disease. The men who skipped breakfast were more likely to be single, smokers, employed full-time, to drink more alcohol, were younger, and were less likely to be physically active than people who ate breakfast. Controlling for a slew of these and other risk factor for heart disease – like alcohol consumption, smoking history, body mass index, regular doctor visits, quality of diet, TV watching, activity level, and sleep habits – did reduce the link between skipping breakfast and heart disease, but didn’t obliterate it. The number of times per day the men ate wasn’t linked to heart risk.
As study author Leah Cahill tells me, the reason that skipping breakfast is linked to coronary heart disease is because it seems to give rise to a group of risk factors that collectively raise heart risk. “Prolonged fasting,” she says, “leads to increases in diastolic and systolic blood pressure, blood concentrations of insulin, triglycerides, free fatty acids and LDL-cholesterol, and to decreases in blood concentrations of HDL-cholesterol.” These are all the textbook risk factors for major heart trouble.
The question then is why skipping breakfast is linked to all of these issues. Cahill says that fasting is a stressful state for the body, so prolonging the fast by not eating when you wake up amplifies the stress. “As we sleep all night we are fasting, and so if we regularly do not ‘break fast’ in the morning, it puts a strain on our bodies that over time can lead to insulin resistance, hypercholesterolemia and blood pressure problems, which can then lead to heart disease.”
She and her team think that it’s all about when that first meal of the day is eaten.
“We believe that it is the timing of how breakfast ‘breaks fast’ in the morning that provides the protection against heart attack that we observed,” says Cahill. “Our bodies need to be fed food regularly in order to maintain healthy levels of blood lipids such as cholesterol, hormones such as insulin, and normal blood pressure.” Perhaps eating earlier reduces the strain on the body that comes of fasting, and/or resets the metabolism.
It’s worth pointing out that this study and others like it seem to question the diets that encourage periodic fasting to reduce weight and/or heart risk factors. There’s also some fairly convincing evidence that calorie restriction can actually help the heart and longevity. But Cahill says that there’s a difference between skipping breakfast and other forms of fasting or restriction, and even the diets that include “fasting days” still make room for breakfast. Additionally, many studies that look at calorie consumption and restriction are done in rodents, which have fundamentally different metabolisms from humans’.
What’s important to note is that metabolism isn’t static – it can change depending on how and when you feed your body. And your cardiovascular health will feel the effects. Of course, eating doughnuts for breakfast probably counteracts the effect somewhat, so choosing reasonable ways in which to break your fast is essential.