Background In today’s busy world, health is often neglected especially among full-time workers. Consequently, lifestyle disorders such as vitamin deficiencies are increasing, perhaps because of inadequate nutrition and lack of sunlight due to long hours working indoors. These deficiencies can lead to various short-term and long-term complications. Objective To estimate serum levels of vitamin B12 and vitamin D3 among vegetarian employees. Methods and materials A questionnaire about dietary and exercise habits was administered to participants who fulfilled the inclusion criteria and provided informed written consent. Participants also were asked about drug and supplement intake, history of smoking and alcohol, specific symptoms of vitamin B12 and D3 deficiency, and sociodemographic status. Blood samples were collected to estimate serum B12 and D3 levels. Results The results indicated that 14.00% of participants were vitamin B12 deficient and 82.00% were D3 deficient. Differences by gender were not statistically significant; vitamin B12 deficiency was identified in 10.00% of women and 14.44% of men, and vitamin D3 deficiency occurred in 100.00% of the women and 80.00% of men. Among 71 participants aged 35-45 years, 15.49% and 91.55% were deficient in B12 and D3, respectively; among 25 participants aged 46-55, 12.00% and 64.00% were deficient in B12 and D3, respectively; among four participants older than 55, no vitamin B12 deficiency was observed, but 25.00% were deficient in vitamin D3 (p=0.00002). Nearly all (96.15%) participants who reported never exercising were found to be vitamin D3 deficient, compared to 77.02% of those who exercised (OR=0.13, p=0.043). No significant association was found between alcohol consumption and vitamin B12 (p=1) or D3 (p=0.713) deficiency. Conclusions The results revealed a prevalence of both vitamin B12 and D3 deficiencies among corporate employees who identified as vegetarians. Increased awareness, dietary modifications, conscious physical activity, and most importantly, attention to one’s health may help improve vitamin sufficiency. Women over age 45 should pay particular attention due to their increased risk of vitamin D3 deficiency. Further research is needed to assess nutrition profiles among other populations to better understand vitamin deficiencies and design adequate preventive measures.