You are unlikely to have measuring cups or spoons with you when you travel, but you still have some tools to estimate portion sizes: your hands!
3- to 4-ounce meat serving/The size of your palm and the thickness of your little finger
1/2 cup of vegetables/The amount that would fit into two cupped hands
1-cup (8-ounce) serving of food/About the size of your fist
1 fruit serving/About the size of your fist
1 ounce of cheese/About the size of your thumb
1 ounce of nuts/One handful