You would weigh very slightly more at sea level than at the top of a mountain, not enough for you to notice, but a measurable amount. ... By one estimate, a person who weighs 150 pounds on the surface of the earth would weigh approximately 149.92 pounds at 10,000 feet above sea level.

Does high altitude make you gain weight?

In this large prospective cohort we observed that participants living at higher altitude had a modest, but significantly inversely associated, average yearly weight gain and a lower risk of developing overweight/obesity.

Does your weight change when you change elevation?

As you travel away from the Earth's surface, your mass stays the same but your weight reduces as gravitational pull decreases. ... But generally speaking, gravitational pull, and therefore weight, is lower on a mountain than at sea level, says Bell.