Methods: A survey on dietary intake and perceived immune status was held among young Dutch women, aged between 18-30 years old. Perceived current immune status was scored on a scale ranging from 0 (very poor) to 10 (excellent). Subsequently, participants could indicate whether they perceived their immune status as normal or reduced. A food frequency questionnaire was completed recording past week food and beverage intake. From this data, the amount of various nutrients could be estimated, including fibers, sugar, tryptophan, beta-carotene, calcium, niacin, folate, thiamin, carbohydrates, riboflavin, vitamin A (retinol), vitamin B6, vitamin B12, vitamin C, vitamin D, and cholesterol. Non-parametric correlations (Spearman’s r) were used to examine the association between perceived heath, immune status and nutritients. Dietary intake of those with normal and reduced perceived immune status was compared using the Mann-Whitney U Test.
Results: N=329 young women (mean [SD] age: 20.7 [2.7]) completed the survey. Significant correlations were found between immune ratings and consumption of tea (r= 0.124, p=0.023), sugar (r= -0.173, p=0.002), and carbohydrates (r= -0.125, p=0.022). N=109 women (33.1%) reported having a reduced perceived immune status. Women with a perceived reduced immune status reported consuming significantly more alcohol (p=0.025), and had significantly higher dietary levels of cholesterol (p=0.022), sugar (p=0.044), and vitamin B12 (p=0.021) when compared to women reporting a normal immune status.
Discussion: The findings show that dietary intake is related to perceived immune status. However, some nutrients have a bigger impact on perceived immune status than others. Future studies, including objective measurement of immune biomarkers and nutrients, should confirm these findings.