I'm someone who naturally sits on the lower end of healthy BMI - 19ish (quite petite). But recently my weight has just kept dropping and I'm now sitting around 17 (lost 5 kg in 8 months). I have been very stressed, but I have been forcing myself to eat, and the weight has not been returning (though goes up during menstruation). I have lots of little niggly things - bad heartburn, diarrhoea, bleeding between periods, low ferritin (resistant to iron treatment with iron tablets) but all have been checked out and nothing found, so I think perhaps stress related? My GP ran a barrage of blood tests (thyroid, hormones, diabetes screen, coeliac, inflammatory markers) and nothing came up. I'm under 40, so the big C is very unlikely, but has been mentioned. Anyone else been able to curtail unintentional weight loss? If it's stress increasing your metabolism what can be done?