Association between daily egg intake and lipid profiles in adults from the Henan rural cohort study

Association of Egg Consumption Frequency and Quantity with Dyslipidemia in Chinese Rural Adults

OBJECTIVE

The aim was to estimate the association of egg consumption with dyslipidemia and its subtypes in Chinese adults.

METHODS

The cross-sectional health survey was conducted in Hanzhong city of Shaanxi province in 2010.Consumption of eggs (alone and mixed in foods) and nutrients were assessed using a semi-quantitative 81-item food frequency questionnaire (FFQ). Serum lipids and other physical measurements were measured by trained medical staff. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated from multivariable logistic regressions. Restricted cubic spline was used to visualize the possible non-linear association.

RESULTS

A total of 2241 participants (mean age, 48.0 years; 34.5% men) were included. The age- and gender- standardization dyslipidemia prevalence was 21.1% in men and 18.4% in women, respectively. Approximately 42.1% of individuals never or rarely consumed egg, while 9.4% consumed ≥2 times/week. The mean egg intake was 21.5 g/d in men and 17.4 in women. In women, after adjustment for demographics and lifestyle factors, the ORs (95%CI) for dyslipidemia and hypertriglyceridemia were 0.57(0.32-1.05) and 0.38 (0.17-0.85) for individuals consuming egg ≥2 times/week, compared with never or rarely consumers. When further adjustment of BMI and dietary factors, the inverse relation persisted for hypertriglyceridemia but attenuated to margin of significance for dyslipidemia (P-trend = 0.050). Increment of 25 g/d was associated with 15% (OR: 0.85, (0.71-1.00)) lower risk of dyslipidemia. Results from restricted cubic splines showed a substantial reduction of the risk within lower range of consumption, which reached the minimum risk around 20-50 g/d (P-nonlinearity = 0.069). No associations were observed in men.

CONCLUSION

Egg consumption was associated with decreased risk of dyslipidemia among Chinese women but not men. Additionally, the beneficial effect tended to be stronger at 20-50 g egg per day. Further study is warranted to validate these findings and clarify the causality.

Association of egg consumption, metabolic markers, and risk of cardiovascular diseases: A nested case-control study

Background

Few studies have assessed the role of individual plasma cholesterol levels in the association between egg consumption and the risk of cardiovascular diseases. This research aims to simultaneously explore the associations of self-reported egg consumption with plasma metabolic markers and these markers with the risk of cardiovascular disease (CVD).

Methods

Totally 4778 participants (3401 CVD cases subdivided into subtypes and 1377 controls) aged 30-79 were selected based on the China Kadoorie Biobank. Targeted nuclear magnetic resonance was used to quantify 225 metabolites in baseline plasma samples. Linear regression was conducted to assess associations between self-reported egg consumption and metabolic markers, which were further compared with associations between metabolic markers and CVD risk.

Results

Egg consumption was associated with 24 out of 225 markers, including positive associations for apolipoprotein A1, acetate, mean HDL diameter, and lipid profiles of very large and large HDL, and inverse associations for total cholesterol and cholesterol esters in small VLDL. Among these 24 markers, 14 were associated with CVD risk. In general, the associations of egg consumption with metabolic markers and of these markers with CVD risk showed opposite patterns.

Conclusions

In the Chinese population, egg consumption is associated with several metabolic markers, which may partially explain the protective effect of moderate egg consumption on CVD.

Funding

This work was supported by the National Natural Science Foundation of China (81973125, 81941018, 91846303, 91843302). The CKB baseline survey and the first re-survey were supported by a grant from the Kadoorie Charitable Foundation in Hong Kong. The long-term follow-up is supported by grants (2016YFC0900500, 2016YFC0900501, 2016YFC0900504, 2016YFC1303904) from the National Key R&D Program of China, National Natural Science Foundation of China (81390540, 81390541, 81390544), and Chinese Ministry of Science and Technology (2011BAI09B01). The funders had no role in the study design, data collection, data analysis and interpretation, writing of the report, or the decision to submit the article for publication.

Egg consumption improves vascular and gut microbiota function without increasing inflammatory, metabolic, and oxidative stress markers

Egg consumption is one of the many inconsistencies in evidence linking dietary cholesterol to cardiovascular disease (CVD). In addition, the gut microbiota and its metabolite, trimethylamine-N-oxide (TMAO), have been shown to play a crucial role in the development of CVD. The fact that egg is rich in choline suggests that excessive egg consumption may increase TMAO production by altering the gut microbiota. However, the effects of egg consumption on vascular function and gut microbiota remain unclear. Here, the diet of nine young male subjects was supplemented with two boiled eggs daily for 2 weeks. Changes in vascular function, inflammation, metabolism, oxidative stress, and gut microbiota were examined. We found that egg consumption increased flow-mediated dilation and decreased brachial-ankle pulse wave velocity. Furthermore, egg consumption positively modulated the gut microbiota function but had no effects on the levels of C-reactive protein, glucose, lipid profile, malondialdehyde, superoxide dismutase, or TMAO. The current study provides evidence that egg consumption improves vascular function, which may be related to the alterations seen in the gut microbiota. Therefore, moderate egg consumption may help to improve vascular and intestinal function in individuals at low risk of developing CVD and other metabolic disorders.