If you were on a planet with weaker gravity than Earth’s, then you would weigh less on that planet. If you were on a planet with stronger gravity than Earth’s, then you would weigh more on that planet. The bigger the planet, the stronger the gravity. Technically, some celestial bodies(like the Moon) aren’t planets but have strong or weak gravity depending on their size. For example, suppose you were on a planet that’s 1/3 the size of Earth,(let’s use my fictional planet Photonis) and your Earth weight is 140 lbs.; then on Photonis, you would weigh 140/3=46+2/3 lbs. You may already know this, but in outer space, you would be weightless since there’s almost no gravity. Gravity also keeps celestial bodies in orbit around other celestial bodies. (You’re actually in a constant state of free-fall!) Of course, gravity is much weaker in deep space than it is on a planet’s surface.

Photonis is 1/3 the size of Earth. In other words, Earth is thrice as big as Photonis.

 There is a difference between being “fat” and being “heavy”. Fat means that you have a big, round torso or a protruding belly; fat bodies have a lot of mass, giving them heavier weight with gravity involved. Heavy means that you weigh a lot, that you have great weight. There is nothing wrong with being heavy as long as you’re in shape. You can be heavy and healthy at the same time.
SuperGravityRoom

Alice thought the scale was broken, but actually she’s in a super gravity room; the strong gravity made her 50 times heavier than normal!

 

Sometimes, your body mass might change a little when you eat foods; it depends on how many calories you consume; low-calorie foods tend to decrease your mass and high-calorie foods tend to increase your mass, so an average amount of calories will allow your mass to stay exactly the same. You burn calories as you use energy, and that can help you lose weight(and mass) if you want to get or stay in shape. However, having a lot of mass or weight doesn’t always mean you’re out of shape. So ladies, if you meet a man that happens to weigh less than you do, it’s no big deal; it doesn’t always mean you’re unhealthy; he just has less mass than you do, not to mention that he could be underweight!