Setting nutrient goals

Yes, you can reset it in Goals to a different percent.

To do that effectively, you need to know what the current percent represents. Normally, MFP uses the percent daily value on US nutrition labels.

If you scroll down the page at this link, you'll find a reference list of those:

https://www.fda.gov/food/nutrition-facts-label/daily-value-nutrition-and-supplement-facts-labels

Just as an example: The reference value for Iron is 18mg. Let's say your personal goal is 20mg. That would be approximately 111% of the standard reference value, calculated as 20 divided by 18, converting the result to a percent. If you change your MFP goal from 100% to 111%, MFP should effectively track against that 20mg/110% instead of 18mg/100%.

I hope that makes sense. If you need more details about exactly where to change this, please reply and let me know whether you're using the web browser version of MFP, or the phone/tablet app. I can even do screen shots if you need that.