“Today” in the context of “for today”

Question

Consider the following sentence:

I ate today.

It can easily translate as:

Hoy comí.

Now consider the following:

How much did you eat today?

In the last sentence, there's a subtle hint of "how much did you eat for today?" Somewhat like, say, you are on a diet and must count your calories. So the doctor asks you about your intake: "How much today?", "How much was it yesterday?". Can this context be translated with a por?

¿Cuanto comíste por hoy?

Please let me know if you need me to explain this better. Not sure if I am being able to convey the context clearly here.

Answer 1

Por hoy is a locución adverbial that means "up to now" or "for the rest of the day"

Ya está bien por hoy

Translates to "Call it a day" or "this was enough for today".

(Por) hoy ya he comido bastante
Ya he comido bastante (por) hoy

In both cases you plan not to eat anythin else for today. You can use either "hoy" and "por hoy" in both sentences, they mean the same and are equally correct.

¿Cuánto has comido hoy?
¿Cuánto has comido por hoy?

In both cases he could eat more after answering the question. Although it seems both forms are correct in this case (I'm checking DRAE) and mean the same, I would never use the second form, it sounds antinatural to me.

Answer 2

I'd use "Cuánto comiste hoy?" sounds natural and it's what we use here (Venezuela).

Answer 3

The context is everything in a word or phrase. If you want to use the phrase as you described it, then I would suggest, as the other two answers do, not to use "por" in it. Even when it is not incorrect, it is just not commonly used in a phrase like yours.

I must add that the original phrase is ambiguous, since when you say "how much", anyone can answer in any way they prefer, since you are not setting a baseline of how much is "a little" or how much is "a lot". Ambiguity aside, in a phrase like this, it is likely that you had a previous conversation about the intake of food. For example:

"Your cholesterol levels are increasing, this is usually due to a high intake on saturated fat for most of my patients. Out of the list I provided you with food high in saturated fats, how much did you eat today?"

If it is a phrase like that one, I would use the following translation for your phrase:

¿Cuánto comiste hoy? OR ¿Qué tanto comiste hoy?

Both phrases express the same idea. You can also use the word "has" (from the verb "haber"), as suggested in one of the other answers. I hope this helps.

Answer 4

Cuánto has comido? Cuánto has comido hoy?

(If it's today then you dont say in past tense)