Am I undereating?

ecl265

I'm 5'5" and probably weigh around 120 or 125 lbs (I stopped weighing myself when I realized I was heading down a borderline eating disorder path). I exercise on an elliptical for around 60 or 70 minutes 6 days a week and do some light strength training a couple days a week too. I'm also usually pretty active; I spend a lot of time on my feet, and now that it's summer, I've been spending a lot of time swimming & hiking. I don't have a whole lot of body fat, but I do have a lot of muscle mass. I don't know how accurate it is, but MFP tells me that my BMR is around 1700 calories and my maintenance a little over 2000 (including my elliptical workouts but not the swimming or other outdoor activities).
I was eating less than 1700 for a long time. I lost my period, felt tired all the time, and had no energy. So a few months ago I started increasing my calories. I think I gained a little at first but then everything evened out again. I've gotten my period two consecutive months in a row now, which hasn't happened in over a year. I noticed I had more energy, was in a better mood, and my legs didn't feel nearly as fatigued as before. I probably eat right around 2000 calories/day now. But for the past week or so, I've been feeling the same way as I did before increasing my calories. I feel drained, lightheaded on occasion, my legs feel heavy while I'm on the elliptical again, and I'm in a bad mood. Usually by the end of the day (like after dinner), I start to feel better/have more energy but sometimes even after eating dinner, I'm still feeling not so great. Should I be eating more? Could I really need over 2000 calories to maintain my weight?
Sorry for the long post. Any advice would be appreciated!!

myfitnesspale3

Absolutely you could be using up all 2000 and much more with activity. Maybe adjust up your MFP base activity level for suggested increased calories.

Re-menses is a good (obvious) indication of a healthier intake.

Not like the gadgets are accurate but maybe a Fitbit or other activity tracker can give you another reference for your activity level.

liznotyet

more calories, more fluid if you are moving more in warmer weather.

williams969

Given your stats and activity level, it sounds like you're still eating at a deficit. Try this calculator: http://scoobysworkshop.com/accurate-calorie-calculator/#results

Hint: I already put your numbers in, even at the 5-6 hr/wk activity level, your maintenance is close to 2300. You sound very active (like the 7-21hr/wk level), and that's closer to 2500 calories a day. This is assuming 120lbs. Looks like you need to eat a lot more :flowerforyou:

ecl265

Thanks everyone for the info & resources!