Expert: Leigh-Anne Persing, PA-C - 5/18/2007

Question
QUESTION: Hi, i'm really sorry I have a really strange and long question about whether my metabolisms 'normal' but it has been on my mind for a while.

I have always been funny about food, since about 11 or 12 years old when I started skipping lunch about twice a week because it was fun to lose two pounds. When I was 15 I stopped eating completely, I only had about 3 or 4 mouthfuls a day, and this went on for a few weeks almost a month until I started to binge and purge. (I had been bulimic for about 3 or 4 years.) In total I went from weighing 115 pounds in April 06 to 91 in July 06, (I am about 5'3') After about four months of disorderd eating (mainly fasting, and my intake never exceeding 200 calories) I started eating three healthy meals a day, which I still have continued till today, but the total of these can't exceed 500 calories or I gain weight. I have tried eating 1000 calories, and more, but I just gain and gain like there's no tomorrow. It frustrates me why I have to eat an anorexic's diet to maintain my current healthy weight? I am 16, almost 17, I weigh about 118 pounds now, in a healthy weight range, which I am really happy with and I feel like I have come out of the eerie isolated world of anorexia and its ideals. I never have had a particularly speedy metabolism, but I gain weight just from eating healthy things and I really wish I could at least have a few biscuits without gaining a pound.

About a week ago I found the condition of having an underactive thyroid. I looked it up and I have quite a few of the symptoms
- Unexplained weight gain
- Increased awareness of the cold
- Cold hands and feet
- Low mood and depression.
(these ones primarily ^)
- And slow movements and thoughts and mistakes
- General Tiredness

I was wondering whether you think these could be signs of hypothyroidism? And whether it is possible it is trigged by disordered eating?
I have been split in half by learning about this condition, on the one hand I am so sure I have an underactive thyroid because everything seems explained, but on the other hand my symptoms (apart from slow metabolism!) are annoying but not really bad - that moodiness and coldness and having a slow metabolism are things that 'just are' and I wonder whether I should just 'deal with them' as my mother says.
Excessive tiredness seems to be the main symptom of hypothyroidism everywhere I read, but I am not really that tired and it could be just a general teenage lack of sleep or soemthing. Is it possible to have hypothyrodism with an emphasis on the other symptoms and not so much on being tired?

I convinced my doctor to let me have a blood test for the box ticked 'Thyroid,' but she didn't really listen to me and my ma doesn't believe I have a slow metabolism either. I'm not really sure what to expect from my results, because my symptoms are not drastic like my ma's friend who was off school for 6 months.

I know I might sound like I worry a lot, but I just was wondering if I was being realistic in considering I have an underactive thyroid? Because I suddenly see a possible solution to the slow metabolism and coldness I thought I would just have forever. It's embarrassing to always have cold hands, and always have people think you're on a diet when you're not overweight and explain you can't eat that muffin because you'll gain weight and no you're not on a diet you just gain weight easily and you can tell they don't believe you. And at lunch all the sandwiches in the shop are 400 calories, which is most of your whole day's intake but you still have dinner to go.

I'm sorry this is horribly long, thankyou for reading this if you got this far
xxxxxx


ANSWER: While a lot of your symptoms are similar to hypothyroidism I would bet that the reason you are having these symptoms is simply because you are not taking in enough calories. I know that you say at 500 calories a day you are able to maintain a healthy weight, but anything about that you gain weight... Consider this: you put your body into starvation mode... your weight is stable where it is at because your body has shut down some other functions of your body (like temperature regulation) in order to preserve energy (calories) for the more important bodily functions. I know it's frightening to see yourself gain weight initially, but I promise you that once your body knows that you are not going to starve it any more, then metabolism will straighten out and you will begin to burn calories more efficiently again. Try increasing your daily intake slowly... maybe increase by 50 calories/day every week. That way it's a slow increase that your body is better able to adjust to. Eating disorders can cause changes in hormones (one of those being thyroid) so it is still possible that your thyroid is a little underactive, but I am leaning more towards your nutrition status as being the culprit. Hope this helps. If you have any other questions please feel free to contact me again.

---------- FOLLOW-UP ----------

QUESTION: Thanks for your answer it's really helped putting things in to perspective.

By increasing your calorie intake slowly like this are you likely to gain some weight in the process? If so, approximately how much do you think it would be? Im really sorry so worried about gaining weight, I just want to understand fully what to expect will happen. It seems so logical and I really want to try really hard to increase it be 50 calories a day every week. I tend to keep off the scales and away from the nutrition information and all things numerical because I'm afraid I'll slip back in to obsession, so I might go over 50 calories, do you think increasing my intake by around 100 calories a day would be too drastic?

Thanks
xxxxx
ANSWER: No, I don't think that's too drastic. in fact, if you were in an eating disorders treatment program they would be increasing your daily calorie intake by 200 calories every week. I just didn't want you to get frustrated and stop trying if you gained more weight than you could handle (mentally). You will gain some weight with increasing your calorie intake. Actually, some people can do the opposite because when you start increasing your calorie intake you jump start your metabolism which can make you burn more calories. So, it can go eitehr way... that's why I thought you may want to start slowly to see how your body responds

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QUESTION: By increasing calories does that not include the ones used up in excercise? I mean, if you ate 700 calories, but excerised and used up 100, would the calorie intake still count as 600? Or do you have to consume 600 calories max?

I don't understand how it works if you increase your calorie intake and you gain weight, how it is helping your metabolism if you are gaining weight anyway? I mean I have a healthy weight I am comfortable with and have healthy eating patterns, and gaining two or three pounds would be okay; but if on increasing an intake eventually up to 1500 caloriesish you would gain 10 pounds or so I think it would be quite a significant gain and I/my parents would be unhappy if I was on the heavy edge of healthy. Is it likely you would gain that much if you enforced it slowly and carefully?  

Answer
You need to take in enough calories to support all of bodily functions... Your body requires at least 1400 calories a day just to take out normal daily activities. If you are eating less than that then some part of your body is paying for it... you may not be able to tell, but in the long-term you may see effects. Eating 600-700 calories a day is not healthy. If I were your parents I'd rather see you eating a healthy amount to support your body, and be on the upper side of a normal weight, than to see you restricting your body to stay on the lower side of normal. Healthy weight range for a person 5'3" is 103.5-126.5