On September 24, 2017, Helou was crowned Miss Lebanon 2017 at Casino du Liban. The pageant was televised on LBCI and LDC. As Miss Lebanon, she competed at the Miss World 2017 pageant. In the final question shew answered the question "In your opinion, can civil societyprotest movements change the reality of Lebanon?" with "protesters should first agree on the objectives to be achieved in order to ensure the effectiveness of their movement".
Helou placed 7th in people's choice, 4th in multimedia and in the top 40 overall among the 118 contestants. She also won the head to head challenge of her group. Helou was among the top 10 in many prediction leaderboards, such as Zardebelleza's leaderboard and others.