The major cause of death globally is chronic diseases linked to lifestyle choices, such as diabetes and cardiovascular disease. Consuming fruits and vegetables is crucial to receiving the critical nutrients the body needs in small amounts. However, there is little knowledge of and intake of this crucial part of nutrition worldwide. The current study postulated a strong correlation between young adults in Riyadh knowledge of and consumption of fruit and vegetables. Hence, the present study aimed to investigate the knowledge of fruits and vegetables among young adults in Riyadh, to investigate the intake of fruit and vegetables among young adults in Riyadh, in addition to investigate the association between knowledge and intake of fruit and vegetables among young adults in Riyadh. The obtained results revealed that 98.3% of the 463 participants who were evaluated at baseline had adequate knowledge of fruits and vegetables, while 1.7% had inadequate knowledge. In addition, we discovered that 91.6% of participants consumed fewer fruits and vegetables than those who consumed more (2.8%). Therefore, for the greatest impact, health promotion messages should specifically target these subgroups of fruit and vegetable intake.