I can't gain weight - is my metabolism too fast?

From this topic

Cecil writes:

Well, yes, for a given definition of healthy. Although the most commonly used equation (Harris-Benedict) to determine BMR assumes that all bodies are the same, a newer equation, the Katch-McArdle equation takes into account body fat content. This means of course that you need to know your body fat content to use the equation but lots of bathroom scales do that these days. Thin people tend to have more muscle and thus a higher BMR than the HB equation would suggest. The above link also points out that BMR isn’t the same as Metabolic Energy Requirement (MER) - this will normally be 20-40% higher than BMR for most desk jockeys (but Cecil did allude to this).

Incidentally, going somewhat off the immediate subject the commonly bandied around figures for recommended daily intake have been around since the 1940s, and were designed for normal-BMI people with a fairly labour intensive lifestyle and thus not appropriate for those with desk jobs who are trying to avoid weight gain.

People might vary a bit as to how well they absorb food - a person’s gut flora is fairly unique to them (I have it on pretty good authority that this is why every person’s faeces has a fairly individual smell) and some bugs are better at playing nice than others. Certainly when the nasty ones get seriously out of hand (we’re not talking the healthy population here) malabsorption can result. My old parasitology lecturer told me that an estimated 10% of the adult human UK population had a Taenia saginata tapeworm living inside them (from eating rare beef) - sadly I didn’t get the source, but these guys can grow to several meters (Diphyllobothrium is a bit more impressive @ 30m IIRC but you’d need to like sushi for that) and are usually fairly asymptomatic. My point being is that you could have one of these issues and be unaware of it.

It would be instructive for the original author to calculate his MER and then track what he eats over the course of a normal week to see whether he’s keeping to that. Web based utilities to do so exist, or I wrote one which is available here (freeware, but teetering between alpha and beta release depending on exactly which version is on there ATM so use at your own risk (bear in mind I only get paid for giving (considerably simpler) nutrition advice to pet owners!)).

For years, I also struggled with not being able to gain weight. And I worried excessively about it. Was it my thyroid? No. Was it my diet? No. Was it stress? Bingo…

After months of unsuccessful cognitive behavioral therapy, reading dozens of books, and even going through a sleep study to rule out some sort of sleep disorder (stress kept me awake at nite), I was finally diagnosed with Generalized Anxiety Disorder.

My doc prescribed a mild anti-anxiety medication, and within 6 months, I had gained 30 sorely needed lbs. For the first time in my life, I had reached a healthy weight that I can easily maintain with no changes in diet.

Not surprisingly, I’m also a lot calmer these days! :cool:

My brother and I have both always had low body fat and difficulty gaining weight, although this was never a problem for us. About a year ago, I decided it might be to my advantage to put on 7 or 8 pounds to help with a sport that I did. I figured I would slowly and methodically add calories to my diet to see how much of an increase was needed. I started by adding another small meal during the day with little results. I increased the size of the meal, but still did not achieve the gain I was looking for. Out of frustration, I then started adding daily doses of olive oil on top of that, which I steadily increased until I got the results I was after. I worked out while this was taking place, so a good chunk of the gain was muscle. The added fat wasn’t a problem, I’ve always had a low body fat % anyway.

Keep track of what you are eating (you may not be eating as much as you think) and start adding calories – you will gain weight.

P.S. I don’t necessarily advocate the olive oil approach, that was more of a personal experiment than anything.

Hmm. Yeah, it could have been stress that was causing you not to be able to keep weight on - part of the “fight or flight” response to to divert blood away from organs such as the gut to more useful things like muscle. An alternative theory is that yes you were stressed and yes the drugs sorted that, but as a side effect they also increased appetite. I can’t speak for humans but valium is a powerful appetite stimulant in cats.

I suppose as far as you’re concerned if both problems are solved it doesn’t much matter whether problem A begat problem B or they both arose spontaneously.