The summer signing from Metz netted his sixth goal in seven games for the Hammers on Saturday during their 3-1 win at Burnley in the Premier League.
While he is keen to praise the 24-year-old for his current form, Allardyce believes that it is important for Sakho to remain focused.
"He's hit the ground well and surprised us all and we just want to make sure it continues. It's my job to make sure he keeps his feet on the ground and doesn't get carried away," he told the club's official website.
"He has so much energy and desire. Before he goes out I can see it in him - he just feels like he's going to score and when we needed him again he delivered."
West Ham return to Premier League action this Saturday when they welcome champions Manchester City to Upton Park.