I am obese with a BMI of over 50. I just got my leptin test back today from my endo. It was 18ng. I am a 38 year old female. My doctor said with my weight, my test should have been 100ng - 140ng. He fears that my body doesn't make enough leptin and I may be leptin deficient. My mother and three sisters are all obese. I does believe this gene deficiency is genetic.
Since leptin deficiency is so rare, he is making me retake the test to double check before he puts me on leptin injections. All my life I have struggled not to gain weight even when I was dieting and exercising. I just kept gaining and gaining even though the thin people around me stayed the same even though their food choices were bad. So I guess I have some messed up obesity gene.
I wish all those horrible doctors who blamed me for my weight my whole life would have just tried a little harder and tested me leptin 35 years ago!