Cardiovascular disease (CVD) is the leading cause of mortality worldwide. An estimated 17.9 million people died from some form of CVD in 2019, accounting for 32% of all-cause mortality that year¹. Associations between diet and risk of cardiovascular complications have long been established, largely relating to alterations in lipid profiles.

For as long as anyone can remember, breakfast has been considered the most important meal of the day. Previous studies² have shown an association between skipping breakfast and increased CVD risk prompting recommendations that up to 30% of one’s daily energy intake should be consumed during the first meal of the day. It has been reported that over 25% of adults skip breakfast. These individuals are often socioeconomically disadvantaged, shift workers, individuals who work particularly long hours, those who suffer from depression or those with poor health literacy². Another study³ showed that skipping breakfast, when compared with consuming a high-energy breakfast, was associated with a 1.6x and 2.6x higher probability of non-coronary and general atherosclerosis respectively, when all other CVD risk factor had been controlled. This suggests a close relationship between eating breakfast and reducing CVD risk, however, the mechanisms and magnitude of this relationship are poorly understood.

Small, dense low-density lipoprotein cholesterol (sdLDL-C) is a smaller form of LDL-C which boasts greater propensity for uptake by arterial tissue, increased proteoglycan binding, and increased susceptibility for oxidation⁴. sdLDL-C concentration is strongly associated with CVD risk, yet once again, the mechanisms of this association remain enigmatic. It is thought that all of the metabolic changes associated with alterations in sdLDL-C concentration collectively contribute to the increased risk of CVD, with the main drivers being its propensity for uptake by arterial tissues and its long circulatory stability⁴

Skipping breakfast and sdLDL-C

A recent study investigated the relationship between skipping breakfast and the effects on lipid parameters⁵. In a cohort of around 28’000 people from the Japanese population, this study looked at the several markers, including sdLDL-C, to develop an understanding of the importance of regular dietary patterns for reducing the risk of CVD.

The study participants were divided into two main categories: breakfast eaters and breakfast skippers. These categories were further subdivided to differentiate men and women, over and under 55 years old, and those who eat staple products (rice, pasta, bread, etc.) and those who did not. The participants contributed blood samples which were tested for several cardiovascular biomarkers: Creatinine, Liver ALT, Total Cholesterol, Triglycerides, direct LDL-C, HDL-C and sdLDL-C.

They found that around 26% of men and 16.9% of women skipped breakfast regularly. Of these, most were considered young and had significant increases in concentration of triglycerides, LDL-C and sdLDL-C compared with those who ate breakfast almost every day.

Table 1. Median concentration of triglycerides, LDL-C, and sdLDL-C for breakfast skippers and eaters⁵

Analyte	Breakfast Skippers (mg/dL)	Breakfast Eaters (mg/dL)
Triglycerides	103	93
LDL-C	124	122
sdLDL-C	34.7	32

This investigation also revealed that in this cohort, 20% of men and 27.3% of women did not regularly consume staple foods as part of their diet and had higher median sdLDL-C concentration.

Table 2. Median concentration of sdLDL-C in men and women who eat or skip staple food products in their diet⁵

Gender	Staple Skippers (mg/dL)	Staple Eaters (mg/dL)
Men	34.1	31.6
Women	25.8	24.7

The data from this study supports the finding that individuals who skipped breakfast had higher sdLDL-C concentrations than those who ate breakfast consistently. Skipping breakfast can therefore be associated with troublesome lipid parameters in both genders and all age groups in the Japanese population. This study suggests that eating breakfast every day is crucial to maintain beneficial lipid parameters and reduce the risk of developing CVD.

The data also show that individuals who skipped staple foods in their meals presented with higher concentrations of sdLDL-C and a higher sdLDL-C/LDL-C ratio, in men and postmenopausal women, when compared with those who included staple foods in their meals. It is becoming increasingly common to remove staple foods from one’s diet due to their high carbohydrate content and the prevalence of low-carbohydrate diets. This data exhibits the importance of maintaining a nutritionally balanced diet to help reduce the risk of developing CVD.

As the first large scale study of its kind, this analysis provides clear insight into the increased risk of CVD associated with not only skipping breakfast, but failing to maintain a nutritionally balanced diet. The major limitation of this analysis is that it only includes individuals from the Japanese population and the same affects may not be seen in populations from other ethnicities. Therefore, further in-depth analysis is required to confirm these findings in other ethnicities

 

Randox sdLDL-C Assay

The Randox sdLDL-C assay employs the clearance method which displays good correlation with the gold standard in sdLDL-C quantification, giving laboratories increased confidence in their results first time, every time. Supplied as liquid ready-to-use reagents, this this test can be applied to a wide range of clinical chemistry analysers, producing results in as little as 10 minutes. Relevant controls and calibrators are also available from Randox as part of the Acusera range.

Randox sdLDL-C Assay Key Features

• Direct, automated test for convenience and efficiency.
• Rapid analysis results can be produced in as little as ten minutes, facilitating faster patient diagnosis and treatment plan implementation.
• Liquid ready-to-use reagents for convenience and ease of use.
• Applications available detailing instrument specific settings for a wide range of clinical chemistry analysers.
• sdLDL-C controls and calibrator available.

References

1. World Health Organization. Cardiovascular Diseases. World Health Organization. Published June 11, 2021. https://www.who.int/news-room/fact-sheets/detail/cardiovascular-diseases-(cvds)
2. Ofori-Asenso R, Owen AJ, Liew D. Skipping Breakfast and the Risk of Cardiovascular Disease and Death: A Systematic Review of Prospective Cohort Studies in Primary Prevention Settings. Journal of Cardiovascular Development and Disease. 2019;6(3):30. doi:https://doi.org/10.3390/jcdd6030030
3. Uzhova I, Fuster V, Fernández-Ortiz A, et al. The Importance of Breakfast in Atherosclerosis Disease. Journal of the American College of Cardiology. 2017;70(15):1833-1842. doi:https://doi.org/10.1016/j.jacc.2017.08.027
4. Rizvi AA, Stoian AP, Janez A, Rizzo M. Lipoproteins and cardiovascular disease: An update on the clinical significance of atherogenic small, dense LDL and new therapeutical options. Biomedicines. 2021;9:1579. doi:https://doi.org/10.3390/biomedicines9111579
5. Arimoto M, Yamamoto Y, Imaoka W, et al. Small dense low-density lipoprotein cholesterol levels in breakfast skippers and staple food skippers. Journal of Atherosclerosis and Thrombosis. 2023;30. doi:https://doi.org/10.5551/jat.64024

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