Breakdown of El médico dice que no debemos olvidar la proteína cuando cambiamos de dieta.
Questions & Answers about El médico dice que no debemos olvidar la proteína cuando cambiamos de dieta.
In Spanish, when decir means “to say / to state that …”, it is followed by que, not de que:
- Correct: El médico dice que… = The doctor says that…
- Incorrect: El médico dice de que… (this is a common error called dequeísmo).
You only use decir de in other meanings, like “to talk about”:
- No dijo nada de ti. = He didn’t say anything about you.
But when you are introducing reported speech (what someone says), use decir que, never decir de que.
Both are possible, but they differ slightly in nuance:
no debemos olvidar
Literally: “we must not / should not forget.”
Deber often expresses duty, recommendation, or moral/ideal obligation. It can sound a bit like advice: “We shouldn’t forget protein.”no tenemos que olvidar
Literally: “we don’t have to forget.”
Tener que is more about practical or external obligation: “We mustn’t forget / we can’t forget.”
In this context, about diet and health, no debemos olvidar la proteína sounds natural in Spain: it’s a recommendation or guideline from the doctor about what is advisable.
Spanish often uses the definite article el / la with nouns that refer to things in general, especially abstract or mass nouns:
- La proteína es importante. = Protein is important.
- El azúcar no es bueno en grandes cantidades. = Sugar is not good in large quantities.
In English you usually omit the article in these general statements (“Protein is important”), but in Spanish it’s very common (and usually more natural) to include it:
- no debemos olvidar la proteína ≈ “we must not forget about protein” (protein in general, as a nutrient category).
After decir que, you can get either indicative or subjunctive, depending on the meaning:
Indicative (as in the sentence):
El médico dice que no debemos olvidar la proteína.
This treats the content as a statement/opinion: “The doctor says (states, affirms) that we must not forget protein.”
You’re reporting what he says as a fact/advice.Subjunctive (indirect command):
El médico dice que no olvidemos la proteína.
This sounds more like: “The doctor tells us not to forget protein.” (He is giving us an order/instruction.)
So debemos (indicative) is fine because the speaker is presenting the doctor’s words as a statement about what we must/should do, not focusing on the act of him ordering us.
Both forms exist, but they are used in different situations:
cuando cambiamos de dieta = when we change diets in general / habitually
Present indicative is used for general truths, habits, or repeated situations.
Here the meaning is: “when(ever) we change diet” (speaking generally about that situation).cuando cambiemos de dieta = when we change diets in the future (one specific case)
Present subjunctive is used after cuando when talking about a future, not-yet-realized event:
Cuando cambiemos de dieta, hablaremos con el médico.
= When we change our diet, we’ll talk to the doctor.
In your sentence, the idea is general advice that applies any time diets are changed, so cuando cambiamos de dieta (indicative) is the natural choice.
Spanish has a common pattern cambiar de + noun to mean “to switch from one X to another X”:
- cambiar de trabajo = to change jobs
- cambiar de casa = to move house
- cambiar de coche = to change cars
- cambiar de dieta = to change diet (to go from one diet to another)
Cambiar la dieta is also grammatically correct but slightly different in nuance. It suggests modifying the diet (changing it) rather than clearly switching from one to another.
In everyday Spanish, for the idea of switching to a different diet, cambiar de dieta is more natural.
Spanish normally omits subject pronouns when the verb ending already shows who the subject is. The endings -emos and -amos clearly indicate “we” (nosotros):
- debemos = we must / we should
- cambiamos = we change
So:
- (Nosotros) no debemos olvidar la proteína.
- (Nosotros) cambiamos de dieta.
The nosotros is usually dropped unless you want to emphasize contrast (e.g., “We (not they) mustn’t forget…”). In neutral sentences like this, omitting it is the default.
Yes, you could say El doctor dice que…, and people would understand you perfectly.
Nuances in Spain:
- médico is the more neutral, formal, and specific term for a medical doctor (profession).
- doctor originally referred to someone with a doctoral degree. In everyday speech, though, many patients do address their médico as doctor.
In written, neutral sentences like this, el médico is often preferred, but el doctor is common in speech, especially as a way of addressing the person:
Doctor, ¿qué me recomienda?
Spanish distinguishes masculine and feminine forms for many professions:
- el médico = male doctor, or generic masculine “the doctor”
- la médica = female doctor
In a real context, you would normally match the actual gender:
- El médico dice que… (male doctor)
- La médica dice que… (female doctor)
The sentence as given uses the masculine, which is often used as a default or example form, but if you know the doctor is a woman, la médica would be more accurate.
In Spanish, the standard position for the main sentence negator no is directly before the conjugated verb:
- No debemos olvidar la proteína.
(We must not forget protein.)
Here, debemos is the conjugated verb, and olvidar is the infinitive that depends on it. So no must come before debemos, not before olvidar:
- No debemos olvidar… ✅
- Debemos no olvidar… ❌ (odd, almost never used)
- Debemos no olvidar only appears in very special, heavy, almost philosophical styles; in everyday Spanish it sounds wrong.
So: no + [conjugated verb] + [infinitive] is the normal pattern.
All three are in the present indicative:
dice
- Verb: decir (to say)
- Person: 3rd person singular (he / she / it / usted)
- Meaning here: “says” → El médico dice… = The doctor says…
debemos
- Verb: deber (must / should / ought to)
- Person: 1st person plural (we)
- Meaning: “we must / we should” → no debemos olvidar = we must not forget / we shouldn’t forget
cambiamos
- Verb: cambiar (to change)
- Person: 1st person plural (we)
- Meaning: “we change” (here: whenever we change diets)
Yes. That sentence is also correct and natural:
- El médico dice que no debemos olvidar la proteína cuando cambiamos de dieta.
- El médico dice que cuando cambiamos de dieta no debemos olvidar la proteína.
Both mean the same. Spanish word order is relatively flexible, especially with adverbial clauses like cuando cambiamos de dieta. Moving that clause earlier slightly highlights the condition (“when we change diet”) first, but the basic meaning doesn’t change.
The original order (putting the condition at the end) is perhaps the most neutral and common in this type of sentence.