The FastDay Forum

http://www.nejm.org/doi/full/10.1056/NE ... 0113231512 is followup correspondence to one of the published twin studies.

[wildmissus]

I'm from a mixed bunch. Brother, father and late granny all underweight, other late granny over weight and the rest of us somewhere inbetween.

Can the fat genes account for all obesity? Obesity is a modern problem so how come we have changed so much, evolution takes a long time. I believe media and marketing have a lot to do with obesity - all those tastey, colourful calorie laden foods who couldn't resist. The choices we have now are ridiculous compared to our grandparents.

I believe a lot has to do with our minds. As I child I was brought up in a negative, fearful environment and as that was ingrained into me anything I achieve is a struggle. So yes, I am (or was) a sucker to things like low fat or health giving foods and the latest chocolate bar as it is always easier/safer to go with the flow than buck the trend. With a lot of help last year I have dealt with that negativity and as a result I have never been so determined to lose weight. That is something I have chosen to do, ie. be a success not a failure.

My highest weight ever was 14st 3lb, BMI30. Now I don't believe it was possible for me to get any heavier, in the same way I know it isn't possible for me to go under 10st. So maybe we have upper and lower limits. We so often talk about the hunger switch here that seems to affect some more than others. Perhaps there is an obesity switch which has inevitably been switched on in many people who have the obesity gene as a result of media and marketing.

TML, Franglaise you both come from obese families, so why are you not obese? Is it because you don't have obese genes or is it because in yours minds you are determined not to be obese, or is it a bit of both?

I know there are lots of contradictions in what I written but that's what we have experts for and I certainly have more questions than answers. I hope one day there will be proper answers for our future children and grandchildren

By the way, my fat granny died aged 83 from a heart attack and my skinny granny died aged 97 form dementia!

I have heard that the unfortunate result of yo yo dieting is that we can grow extra fat cells to accommodate putting on weight but that when we lose weight we cannot then also lose the extra fat cells we acquired? I think the best we can do is reduce the fat in those cells when losing weight but when maintaining a new weight that is one reason why it is difficult because those fat cells can readily return to storing fat again. I' m sure any nerdy types will correct me if I'm wrong! But it is a depressing thought that our bodies cannot completely recover from having once been over weight.

[carorees]

Yes, Isis, there does seem to be truth in that...I'm still looking for some research to show that it is possible to reduce the actual number of fat cells

This program has interesting facts on genes affecting weight, virus causing weight gain and body weight set points. If you have the time, it is interesting.

http://www.youtube.com/watch?v=SeeFrcvt3KA

I'm talking about obesity. It runs in my family, that's how I know it.

that can be as much about learned behaviours and eating patterns as about anything medical. You did say you would eat crap all the time if given the chance

Phil, this is not a joke. 3 members of my family (a mother and her two daughters) were diagnosed with a genes' abnormality which causes obesity.
Obesity can be a disease and has nothing to do with eating habits or whatever.

Wildmissus, I don't come from an obese family. Both my parents are slim, all my grandparents were slim and so were my great-grandparents.
I have an aunt and two cousins who have this particular gene. I certainly don't have it because if I did I would be obese. My aunt spent all her life trying to lose weight, my cousins do the same. One of them did, but it was a complication from another health problem and she can gain it back any minute now.
After my thyroid and various other health problems, I realised that being determined to stay thin is not enough.

Yes, Isis, there does seem to be truth in that...I'm still looking for some research to show that it is possible to reduce the actual number of fat cells

Ah, I doubt that you will. To my knowledge, fat cells' number is stabilised when we are teens. If we're lucky to be thin kids/teenagers then even if we gain weight as adults we will lose it more easily and won't easily gain it back.

Obesity can be a disease and has nothing to do with eating habits or whatever.

Doubtless genes can predispose people to obesity, as can various conditions, but to any of them actual guarantee obesity as a certain outcome ? or for that matter prevent weight loss ?

As it said in the correspondence linked above "I was gratified to see Dr. Sims point out in his editorial that genetic factors represent heritable tendencies and that they are not an irrevocable sentence of obesity." which suggests the answers are "no".

I don't know what Dr Sims says, I don't even know who he is.
All I know is that 3 people who were skinny got obese after they turned 18, without eating more than any normal person and that after years of diets without results and tests and doctors' visits they finally got their answer.
I'm not saying that all obese people have this abnormality (it is quite rare) but it can happen...

[quote="wildmissus"]I'm from a mixed bunch. Brother, father and late granny all underweight, other late granny over weight and the rest of us somewhere inbetween.

Can the fat genes account for all obesity? Obesity is a modern problem so how come we have changed so much, evolution takes a long time. I believe media and marketing have a lot to do with obesity - all those tastey, colourful calorie laden foods who couldn't resist. The choices we have now are ridiculous compared to


I think you are absolutely right. We have the same genes we have always had which probably evolved so that we would store fat in times of plenty so that we would survive frequent periods of starvation. What has changed is our environment. High fat, high calorie delicious food everywhere we turn, no periods of starvation (until 5:2 ) and jobs that require us to sit for 8-10 hours per day. Add that to the fatty genes and you are in difficulty.

And then there is the emotional eating/comfort eating side of things which like wild issues I learned very well in childhood.

Just my thoughts

[wildmissus]

Just watched the youtube video that simcoeluv linked above (another Horizon documentary). It's eye opening and I'm bit speechless. It does support what TML and Isis have said and I think Caroline will have trouble finding research on reducing the number of fat cells because it is not possible. It is one of those programmes that leaves you wondering what to do and is there any point even trying to lose weight. The programme did not however cover what byoung has mentioned. ie, environment.

TML, Like you I am determined to lose weight and I'm going to keep going as I was a really skinny child so at least I have a chance of getting there.

Determination is half of success.

You know we hear in the media all the time about genes being the cause for things like breast cancer etc...last year I met a geneticist at dinner and she said that genetics are a tiny cause of disease (I'm not quoting her properly) and that mostly it is lifestyle factors that come into play. I DO believe our body shape/type comes into play - when I see all the women that come down the genetic chain from my grandmother Madge, they just about all have the same body shape, shortish, hourglass figure, tend to overweight. These people live in many different countries around the world, some never met Madge and their parents didn't eat the same old stodgy diet that Madge & Fred did, so I think their genes definitely come into play. But at the end of the day a diet filled with vegies, low GI carbs & protein will keep a person healthy

But at the end of the day a diet filled with vegies, low GI carbs & protein will keep a person healthy

Sadly, no. If your body decides to misbehave then what you eat is irrelevant.