I used to do the same, but not anymore.
At the Elevation it would be best to look at Christ. If I am not mistaken, this is the significance of the liturgical element of the Elevation. It is also why bells are rung many times at this point: to call the faithful’s attention towards what is happening. In the past, bells used to ring a total of 10 times throughout the Elevation of the Body and Blood of the Lord.
The Elevation used to consist of the following: kneel, lift, kneel. During the time when the priest kneels, it was proper to offer some sign of humbleness such as indeed lowering our head or closing our eyes, but during the time when the Lord is held up high it was proper to look at Him, love Him, and there were even indulgences attached to the silent prayer of the words: “Dominus meus et Deus meus”, “My Lord and my God” while looking at Him.
St. Andrew’s missal (1937) states:
“The consecrated species are thus shown to the congregation as a protest against the heretics who denied the Real Presence. Pius X granted an indulgence of seven years to all who, looking on them, said: ‘Dominus meus et Deus meus. My Lord and my God.’ To all such as do so daily he granted a plenary indulgence once a week provided they receive Holy Communion, subject to the usual conditions except the visit (Pius X, 1907; Pius XI, 1937) It is however forbidden to say this invocation aloud. (S.C.R., Nov. 6, 1925)
Obviously it is not wrong or bad or anything negative if you simply bow or close your eyes But I think this way you may be missing out on something wonderful and edifying.