Abstract
The study aim was to investigate differences in nutritional, cardiovascular and lifestyle status of ‘health conscious’ subjects. In a partial ‘lock-down’ during the COVID-19 pandemic period, we performed a web-based, cross-sectional study. We compared 80 self-selected subjects (51 vegans, 67% females, and 29 non-vegans, 55% females, p = 0.344). Nutritional status was assessed by bioelectrical impedance and standardized food frequency questionnaires (i.e., contribution of nutrients from foods and supplementation, combined and separate). Serum lipid concentrations and blood pressure (BP) were assessed from annual or initial examination reports, while sociodemographic, economic, and lifestyle statuses were obtained by standardized questionnaires. Finally, a multivariate linear regression model was used to estimate the relationship between total fiber and saturated fatty acid (SFA) intake and low-density lipoprotein cholesterol (LDL cholesterol) values. The vegans had a significantly lower body mass index (22.8 ± 2.4 vs. 26.6 ± 3.6 kg/m², p < 0.001) and body fat % (19.3 ± 7.3 vs. 25.8 ± 8.2%, p < 0.001) than the non-vegans. There were significant differences between vegans and non-vegans in energy intake, and most macronutrient (10/12) and micronutrient (15/23) intakes in units/day. Both diets were well designed, with high fiber and low SFA and free sugar intake but remained insufficient in n-3 long chain polyunsaturated fatty acids (for vegans), vitamin D, calcium, sodium (for vegans) and iodine. Vegans also had a significantly lower lipid profile and BP than non-vegans, except for high-density lipoprotein cholesterol. However, both groups met targeted recommendations. Furthermore, fiber and SFA intake and age explained 47% of the variance in LDL cholesterol. In conclusion, ‘health conscious’ vegans and non-vegans with comparable lifestyle statuses had significant differences in dietary intake, body composition and cardiovascular health status.
Generated Summary
This cross-sectional study investigated differences in nutritional, cardiovascular, and lifestyle status between health-conscious adult vegans and non-vegans from Slovenia. The study utilized a web-based survey during the COVID-19 pandemic to compare the dietary intake, body composition, and cardiovascular health markers of the two groups. The research aimed to determine whether there were significant differences in these areas, particularly as related to the well-designed dietary patterns. Participants were self-selected, and data collection included bioelectrical impedance, food frequency questionnaires, and assessment of serum lipids and blood pressure. Sociodemographic, economic, and lifestyle data were also gathered through standardized questionnaires. Statistical analysis was performed using R. Multivariate linear regression was used to estimate the relationship between fiber and SFA, intake and LDL cholesterol, adjusted for age, sex and smoking. The study aimed to provide insights into whether vegan diets, compared with non-vegan diets, among ‘health conscious’ adults and in sociodemographic- and lifestyle-matched groups translate into differences in body composition and CV health status.
Key Findings & Statistics
- The study included 51 vegans (67% female) and 29 non-vegans (55% female).
- Vegans had a significantly lower body mass index (BMI): 22.8 ± 2.4 kg/m² compared to 26.6 ± 3.6 kg/m² in non-vegans (p < 0.001).
- Vegans also had a significantly lower body fat percentage: 19.3 ± 7.3% versus 25.8 ± 8.2% for non-vegans (p < 0.001).
- The mean energy intake was significantly higher in vegans than in non-vegans: 2399 ± 507 kcal versus 1998 ± 419 kcal (p < 0.001).
- Mean fiber intake was significantly higher in vegans: 75 ± 16 g/day versus 34 ± 10 g/day in non-vegans (p < 0.001).
- The mean SFA intake was 7 ± 2 g for vegans and 20 ± 9 g for non-vegans, p < 0.001.
- The mean cholesterol intake of the non-vegans was 385 ± 507 mg/d.
- The intake of vitamin B12 was higher in vegans and non-vegans than recommended.
- The intake of vitamin D was lower than recommended in both groups.
- The LDL cholesterol was significantly lower in vegans: 1.7 ± 0.4 mmol/L compared to 2.8 ± 0.7 mmol/L in non-vegans (p < 0.001).
- The mean HDL cholesterol in vegans was 1.4 ± 0.4 and 1.5 ± 0.5 in non-vegans, p = 0.300.
- Triglycerides were significantly lower in vegans: 0.8 ± 0.3 mmol/L versus 1.4 ± 0.9 mmol/L in non-vegans (p <0.001).
- The systolic blood pressure was 113 ± 11 mmHg in vegans and 120 ± 12 mmHg in non-vegans, p = 0.012.
- The diastolic blood pressure was 69 ± 8 mmHg in vegans and 76 ± 10 mmHg in non-vegans, p < 0.001.
- Multivariate regression analysis showed an inverse relationship between total fiber intake and LDL cholesterol (β = -0.012, p < 0.001).
- SFA intake was found to be positively associated with LDL cholesterol (β = 0.026, p < 0.001).
- Fiber and SFA intake alone explained 43% of the variance in LDL cholesterol, with age adding another 4%.
Other Important Findings
- The study found that vegans and non-vegans chose health as their primary motivation for their dietary patterns.
- Vegans and non-vegans had good sleep quality and patterns, with no significant difference between the groups.
- Vegans consumed significantly more from 11 out of 16 plant-based food groups.
- EPA plus DHA intake among vegans was lower than among non-vegans.
- Both groups had plasma lipid profiles (i.e., LDL cholesterol levels <3 mmol/L and triglyceride levels ≤1.7 mmol/L) and BP within recommended values for the primary prevention of CV disease.
- Vegan diet was associated with a more favorable body composition status than non-vegans.
- The non-vegans skipped all main meals more often than vegans, and the largest difference was with breakfast.
- Non-vegans had lower fiber and higher SFA intake.
- Both vegans and non-vegans reported low transport time, relatively low weekly and weekend prolonged daily sitting, and high amounts of walking, moderate-intensity, vigorous-intensity and total PA.
- Vegans consumed vitamin B12 in isolated form, while the non-vegans consumed sufficient vitamin B12 with foods.
- The mean HDL cholesterol in vegans (1.4) and non-vegans (1.5) were within the “optimal” range of 1–2 mmol/L
Limitations Noted in the Document
- The study design was cross-sectional with self-selected and self-reported data, which might not be generalizable to all vegan and non-vegan diets.
- The possibility of reporting bias existed due to the self-reported nature of the study.
- The number of participants was limited.
- The study did not include table salt intake in its sodium and iodine analysis.
Conclusion
The study’s findings indicate that health-conscious vegans have a more favorable body composition and cardiovascular health status compared to similarly health-conscious non-vegans. The results underscore the potential benefits of a well-designed vegan diet, characterized by higher fiber intake and lower saturated fat intake, for improving cardiovascular health. Although the study did not establish causality, the observed differences in lipid profiles, blood pressure, and body composition suggest that a vegan lifestyle can positively influence these health markers. The study’s emphasis on matching lifestyle factors, such as physical activity, further supports the idea that dietary choices and health outcomes are interconnected. The study results also showed the importance of having high-fiber and low-SFA and free sugar intake, which supports the need for well-designed dietary patterns. These findings are significant because they suggest that, among individuals with comparable lifestyles, dietary choices play a key role in cardiovascular health and body composition. The fact that both groups exhibited similar levels of physical activity and other lifestyle factors strengthens the association between diet and health outcomes, suggesting that dietary choices, particularly between vegan and non-vegan diets, can influence these health metrics. In addition, the fact that mean HDL cholesterol in vegans (1.4) and non-vegans (1.5) were within the “optimal” range of 1–2 mmol/L. In conclusion, this study provides valuable insights into how dietary choices impact health, supporting the idea that a healthy vegan diet can be an effective approach to improving cardiovascular health and body composition among health-conscious adults. However, further studies are needed to confirm these findings and explore the specific mechanisms underlying these effects in more detail.