Yes, you can have cream cheese and heavy cream while on a low-carb and keto diet, but you just need to be watchful of the serving size and the carbs in each serving. In regular Philadelphia Cream Cheese, there is 1 net carb per 1 ounce serving. Heavy cream can be a bit misleading. Heavy cream is is labeled as 0 carbs per tablespoon but is actually 0.4g. Those extra carbs can add up in a recipe like this one, which has multiple servings of heavy cream.