Hi
Welcome to the MedHelp forum!
There are many causes for unexplained weight loss and since your husband is eating a lot and losing weight, worms in stool should be ruled out first—tapeworm, round worm, giardiasis, etc. Hence a stool test is a must. The second thing to rule out is hyperthyroidism. Other causes are depression, anorexia nervosa, AIDS, cancers especially colon cancers, drug abuse, infections and loss of appetite. Increased metabolism as in hyperthyroid states, HIV, cancer etc also cause weight loss. Poor absorption as in irritable bowel syndromes and malabsorption syndromes too is possible. Malabsorption syndromes are seen in intestinal tuberculosis, HIV, tropical sprue, parasites in stool and Whipple’s Disease. Several other causes have been looked into.
Discuss this with your husband’s treating doctor. It is difficult to comment beyond this at this stage.
Hope this helps. Please let me know if there is any thing else and do keep me posted. Take care!
A friend of mine gained 30 lbs in one month despite being a marathon runner and eating very healthily. It turned out that she had a benign pituitary tumor. It was removed and she was fine. I believe a tumor can also cause overproduction of hormones as well as block the production of hormones as it did in my friend's case. I am sure they will be checking for this. It is good that they are thoroughly checking his thyroid as that is another likely culprit.
Good luck.