Susan has excellent youtubes on dehydrated products - imstillworking. She recommends that you try out the products now before they’re needed because the serving sizes may not be accurate such as dehydrated onions. She found that they do not reconstitute to the amount shown on the label. IOW, you’re going to run out of food before you expected.
The serving sizes suggested on the label is enough to nourish and nutrionally maintain the body - but you wont thrive or put on any weight.
I believe the portion sizes were designed for a dwarf - it is not uncommon for someone to have two or more portions to feel satisfied and satiated.