How do we define healthy? Is it a list of good and bad? Or is it about how we feel?
It is probably somewhere in between because even a healthy meal per definition can become unhealthy in excess. So a healthy meal is about balance.

A balanced meal is both about content and proportion.
Balance is both in relationship to its components but also in relationship to you, your environment, and your activities. Not to mention your state of mind and emotional situation.

A healthy and balanced meal will give you the possibility to feel and live the way your were meant to live; relaxed yet strong, focused and with high constant energy, with a positive outlook and stabile mood.
Choosing the healthful way of course also means the added benefit of prevention against lifestyle diseases.

You would want to think of balance in all your meals.
You also want to adjust your choices throughout the day to reflect what is going on and what you need to stay balanced.

Mornings: Breakfast is a very important meal and helps you set the tone for the day. You need it to stabilize your bloodsugar which provides you with energy to the ability to stay focused. The best choices for this is a serving of wholegrain.

Lunch: We need lunch to give us the next power charge to get through the rest of the day. Skipping lunch means running on empty for the rest of the day. Don't do it. You need a good serving of complex carbohydrates to keep your energy going and some protein to keep you full, satisfied, and provide the energy that keeps you active.

Dinner: Is the most misused meal because we don't need much at this time, we are getting ready to close down for the day, but most have not nourished themselves all day so the feast is dinner time.

Keep dinner light. Choose light foods based on green leafy and vegetables, maybe a little protein is needed but just remember, you are off to bed soon and so is your body, which means, it needs to use up what you feed it before bedtime.