Learn Hardcore Japanese: reitousyokuhin toka insutantoraamen toka bakari tabete iru to, eiyou ga tarinaku naru kamo siremasen. - If you eat only frozen food and instant ramen and such, you might not get enough nutrition.

Putting とか after each listed item (except sometimes the last) makes it feel like “X and Y and that kind of thing”, not an exact, closed list. It sounds a bit casual and vague on purpose.

You could think of it as:
A とか B とか → “A, B, etc.; A and B and such”

How is とか different from や or と in this kind of list?

Roughly:

AやB
“A and B (and possibly others)” – neutral/polite, good in writing and speech.
AとB
“A and B” – usually a complete, specific list (though context can soften this).
AとかBとか
Informal, gives a sense of “A, B, and stuff like that / and so on”. Often sounds more casual and spoken.

So:

冷凍食品やインスタントラーメンばかり食べていると…
“If you only eat frozen foods and instant ramen (and similar things)…”
冷凍食品とかインスタントラーメンとかばかり食べていると…
Similar meaning, but more conversational and “roughly listed” in feel.

Why is there no を after インスタントラーメン?

The direct object marker を is simply omitted, which is very common in spoken Japanese when the meaning is clear.

The underlying structure is:

冷凍食品とかインスタントラーメンとか（を）ばかり食べている

So grammatically it’s:

“[things like] frozen foods and instant ramen (as objects), eat nothing but (them)”

Because the verb 食べている clearly needs a direct object, and that object is obviously the listed foods, を can be dropped in natural conversation.

What exactly does ばかり mean here?

Here ばかり is a particle that means “nothing but / only (and that’s a problem)”.

冷凍食品とかインスタントラーメンとかばかり食べている
= “(someone) is eating nothing but things like frozen foods and instant ramen”

Nuance:

It’s not a neutral “only”.
It often carries a negative or critical feel: “only doing X and that’s not good / that’s too much”.

So the sentence implies that the diet is unbalanced and undesirable.

What’s the difference between ばかり食べている and だけ食べている?

Both can be translated “only eat”, but they feel different:

～だけ食べている
→ more neutral: “eat only ~” (just stating a fact).
～ばかり食べている
→ often implies excess / imbalance / complaint:
“eat nothing but ~ (too much of it / that’s bad)”.

In this context:

冷凍食品とかインスタントラーメンとかだけ食べていると…
= “If you eat only frozen foods and instant ramen…” (relatively neutral)
冷凍食品とかインスタントラーメンとかばかり食べていると…
= “If you keep eating nothing but frozen foods and instant ramen…”
with a stronger sense that this is a bad habit.

Why is it 食べている and not just 食べる?

～ている here expresses a continuous / habitual action:

食べている can mean:
- “is eating (right now)” (progressive), or
- “(habitually) eats” (habit/state).

In sentences like:

A ばかり食べていると…

it usually means “if you keep eating / if you habitually eat”.

If you said:

A ばかり食べると…

it would still be grammatically correct, and often understandable as generic/habitual “if you eat A only, then…”. But 食べている sounds more like an ongoing lifestyle habit, which matches the “diet” context better.

How does ～ていると work as a conditional (“if”)?

The pattern is:

(verb in ～ている form) ＋と
→ “if / when (you are in the state of doing ~)”
→ often “if you keep ~ing / when you (habitually) ~”.

So:

ばかり食べていると
= “if (you) keep eating only (those things)”
= “when/if your habit is to eat only (those things)”.

Here と is the conditional “if/when”, not the quoting と.

In 栄養が足りなくなる, what is happening grammatically with 足りなくなる?

Breakdown:

足りる = “to be enough / to suffice” (an intransitive verb)
Its negative form: 足りない = “not enough”
To say “to become not enough”, Japanese often uses:
- adjective (or adjective-like form) + なる

Here we treat 足りない like an adjective and put it into the stem used before なる:

足りなく + なる → 足りなくなる
= “to become not enough / to end up insufficient”.

So 栄養が足りなくなる literally means “the nutrition becomes not enough” → “you end up not getting enough nutrition”.

Why is 栄養 marked with が instead of は or を?

In 栄養が足りなくなる:

栄養 is the subject of the verb 足りなくなる (“to become insufficient”).
The pattern is:
- X が足りる / 足りない / 足りなくなる
  = “X is enough / X is not enough / X becomes not enough”.

So が is the normal subject marker here.

If you used は, e.g. 栄養は足りなくなる, you would be putting contrast or topical emphasis on 栄養, like “as for nutrition, it becomes insufficient (as opposed to something else)”. が is the default, neutral subject marking.

What nuance does かもしれません add? Is it different from かもしれない?

かもしれません and かもしれない both mean “might / may / it’s possible that…”.

かもしれません
→ polite: used with です／ます style
かもしれない
→ plain/casual: used in informal speech or plain-style writing

Function:

足りなくなるかもしれません
= “it might become insufficient” / “you might not get enough”.

Nuance: it expresses uncertainty. The speaker is warning of a possibility, not stating a certainty.

Spoken contraction かも (without しれない/しれません) is even more casual, e.g.:

足りなくなるかも
Very casual: “Might not be enough.”

Can I say 冷凍食品やインスタントラーメンばかり食べていると instead of using とか?

Yes.

冷凍食品やインスタントラーメンばかり食べていると…

is perfectly natural and maybe a bit less casual than using とか. The meaning would still be:

“If you keep eating nothing but frozen foods and instant ramen…”

The nuance difference:

や → relatively neutral “and / and such”
とか → more colloquial; gives a softer, “for example / like X and Y and that kind of thing” feeling.

Both are very common in conversation.

Is the overall sentence polite, casual, or in-between?

It’s mostly polite, but with a slightly casual flavor from とか.

かもしれません → polite ます-style
No plain-form endings like だ or ～ない at the end
Vocabulary is neutral

Using とか for listing is a bit casual, but it’s totally fine even in many polite conversations. So you can think of it as polite but conversational, suitable for everyday speech, advice, or warnings.