 [ Symptoms ] i have a very high metabolism and i can not gain weight how can i lower my metabolism while exercising more  i am 20 years old 6 tall and weigh only about 150 155 i am also not very active i want to start running and lifting weights but it is tough for me to gain muscle because i have a very hard time putting on weight what can i do to lower my metabolism enough to start putting on weight and getting bigger i also do not eat very well but tend to eat a descent amount of protein every day [ Disease ] it could be a number of things my experience has been overly stressed and worked out due to my job being physically demanding causing a late period there could be a possibility that you are pregnant and your levels would not be high enough to make a positive read i had that happen my first pregnancy and had to take another test 2 weeks later and then came out positive your best bet is to put it in the back of your mind for now so you do not stress yourself out thinking about it it is a 5050 chance of going either way you are pregnant or your period has delayed for a bit