I think that as a long as it is occasional, it is okay. But I would not make a habit out of eating that little.
In a way our bodies are machines and we need fuel. I eat to support my body's health and activities (mostly, I also eat sometimes for pleasure, but I really try to toe the line for health).
I run most mornings. I have been running about 3-4 miles and when I come home I am ravenous. So I usually have no problem eating after a run. Today I pushed up my mileage to 7 miles. I was surprised when I got home that I was NOT hungry. Very strange for me.
I ate anyway. My body needs fuel. I need to replace the carbs I burned and make sure I protect my muscle. I need fiber and fats to keep my body working right. I need protein to keep me full and going until my morning snack. If I chose to not eat because I was not hungry, I think that would have been a poor choice. My body needs breakfast and fluids after a 7 mile run. No questions.
One of the mantras of weight loss is: eat breakfast! I've been here long enough to see how many people eat before they start their weight loss journey. Many people with weight problems don't eat breakfast, often wimp out on a good lunch, but then eat a lot of calories for dinner. Experts often advise breakfast as an important part of weight control.
I look at my body like a furnace. I need to keep feeding it fuel consistently to keep it running in top form. I know that, for me, not eating enough is as bad for my body as eating too much. So I plan what I eat and I eat what I plan. Period. The other night, I was still hungry after I ate my planned dinner. Oh well. I drank water, had my calcium (that I always have at the end of the day--it signals "no more eating" and I posted here to write out my commitment and get some support). My brain caught up to my stomach and I was content.
This am, not hungry after my run. Oh well. I need carbs and protein and fat and blueberries (yes, I consider blueberries to be their own food group
). My hunger button is busted so I have to plan my nutrition to keep my body running at top form.
Anyway, a long post to say that I think occasionally, it is okay to go low. But you want your body to stay confident that there is plenty of healthy food available so that it runs at top form and doesn't try to be miserly about the calories you do eat.
Think about sneaking in some nutrient dense calories on those days. Add avocado to your sandwich. Stir peanut butter into your oatmeal. Snack on some almonds or cashews. Good luck!