Copyright Medical News Today
The authors of the current review noted the wide variation in study results when it comes to skipping breakfast and metabolic syndrome risk. This systematic review and meta-analysis was conducted by researchers in China and sought to examine the relationship between not eating breakfast and risk for metabolic syndrome in the general population. Researchers searched databases, including PubMed and the Web of Science, and identified studies that met their inclusion criteria. For example, the study had to focus on the general population, and metabolic syndrome, or individual components of metabolic syndrome, had to be outcomes. They excluded studies for a few reasons as well, such as those that were not observational, or some that focused on certain special groups like individuals with diabetes. At least two reviewers were involved in assessing the quality of the studies. In the end, researchers included nine studies, which allowed them to look at data from 118,385 participants. The findings suggested that skipping breakfast was associated with an increased risk for metabolic syndrome. Researchers then looked at how skipping breakfast related to specific components of metabolic syndrome. Studies out of the United States and Japan did not find an association between skipping breakfast and abdominal obesity, but the study out of Iran did. Pooling the data together, skipping breakfast was linked to a greater chance of having abdominal obesity. Five studies examined how skipping breakfast linked to the risk of high blood pressure. The overall pooled analysis found that skipping breakfast increased people’s risk for high blood pressure. The researchers observed similar findings for skipping breakfast and the risk for high blood sugar and hyperlipidemia. When it came to heterogeneity, researchers did observe it, primarily for skipping breakfast and the risk for metabolic syndrome, high blood pressure, and high blood sugar. However, they were able to account for heterogeneity and see if the association remained significant, which it did for these findings. The paper further discusses the reasons for the observed results. For example, it notes that skipping breakfast may impact metabolic health and “the body’s ability to process nutrients” by breaking the body’s natural rhythm. The discussion section also nores that skipping breakfast is associated with “good” cholesterol levels, total cholesterol, “bad” cholesterol, and triglycerides. Overall, the results suggest the benefits of the “most important meal of the day.” Mir Ali, MD, a bariatric surgeon and medical director of MemorialCare Surgical Weight Loss Center at Orange Coast Medical Center in Fountain Valley, CA, who was not involved in this research, commented to Medical News Today that: “This study is in line with other studies that showed that eating breakfast has important benefits. Eating breakfast can stimulate the metabolism and provide the energy needed to function well. Also, by eating breakfast, it may help someone eat less throughout the day.” This review does have some limitations. This review only focused on three types of studies — cohort, cross-sectional, and case-control — and only so much information can be drawn from these study types. Most of the final studies included were cross-sectional and the rest were comparative. The researchers noted that since the studies were observational, there is a risk for confounding. Observational data further cannot determine that skipping breakfast causes metabolic syndrome or its components. When looking at the individual components of metabolic syndrome, researchers reported on hyperlipidemia rather than the individual components of high triglycerides and low “good” cholesterol. More research into these individual components may be helpful in the future. The other big limitation that the authors noted is that the studies assessed eating breakfast and outcomes differently. This may then lead to measurement bias and “affect the consistency of the results.” The criteria and methods the researchers used, such as only including studies written in English, and the databases they used may have impacted the results. The authors also admitted that the “observed event rates were generally low and some raw data were incomplete.” It is also important to acknowledge the differences in study results, although the researchers did try to account for this. Individual studies also showed differing results at times for men versus women. Finally, the researchers also took time in the review to discuss the difference between skipping breakfast and observing patterns of intermittent fasting. They noted that skipping breakfast typically shows that someone eats in a way that is unstructured and uncontrolled. Skipping breakfast is also linked to “other unhealthy lifestyle behaviors” and leads to eating more food later on in the day. By contrast, intermittent fasting is something that is a conscious choice, and people who practice it often also follow a healthy lifestyle. More research into the underlying reasons why researchers observed the results they did may be beneficial.
