Sport Slow/Fast metabolism...??

[Wrangell]

It's an interesting concept but I think not.. At least, I've never heard of any evidence/suggestion even that bad eating habits are hereditary.. I'd be surprised if there is any link myself.. But on the other hand, if you take the template of the drinking issue being hereditary, there's no reason why it shouldn't theoretically apply to food..

I'd have to go back and check, but I think there may have been some studies on adopted kids and separated twins that ( when you remove the environment / learned behavior component ) suggest a strong genetic link - a ' family history ' if you will - to alcoholism.

I think this may be one situation where nurture takes over from nature, in that, the kid sees the parents reckless eating behaviour and then copies, as children do

If nurture carries the day then you would expect adopted kids of alcoholic birth parent(s) - raised by non-drinking parents who adopted them - to be at no greater risk of alcoholism than anyone else ( i.e the general population ).

Similarly, you would expect adopted kids of obese birth parent(s) - raised by non-obese parents who adopted them - to be at no greater risk of obesity than anyone else.

Wonder if that is really the case ? I'll have to look into this a bit more.

.. As for genetics (i.e. via DNA), I don't think that plays a huge part.. Then again, is this situation nature or nurture? :- baby in the womb who at some point during pregnancy starts to get a taste for sweet stuff that the mothers eating.. Surely that's nurture?

Well, it isn't sweets per se that make you obese / fat ...it's excess calories.

So, it's hard to say.

Then again, maybe the mother has an abnormal genetic disposition to crave sweets - or alcohol.

 

[Wrangell]

Well, that's just it: we've primarily been focused on the physical aspects of genetically influenced obesity, but don't forget that there's a strong psychological and neurological aspect to it as well: terming the difficulty that some people have with sticking with a diet or exercise routine can have as much to do with actual neurologically induced issues as it can have to do with anything else...again, this doesn't mean that these issues cant be overcome with effort, but think about this: we accept that alcoholism is strongly affected by heredity, that depression, anxiety, attention-deficit, etc, are all neurologic disorders, but then we turn around and claim that obese people that can't stick to a diet, basically doing what we are genetically programmed to do in order to survive (i.e. consuming in times of prosperity in order to survive in times of famine: 60 years of McDonalds and easily available food isn't long enough to alter our genetic programming), are in fact "lazy" and should be shunned. The fact is, 5000 years ago, the body-type that we covet, the lean and slender individual, would be a sign of poor health because they would be less likely to be able to survive during stress and starvation. These individuals are following a genetically programmed plan that had been successful in keeping the human species alive for hundreds of thousands of years. Our genetic purpose is to live long enough to give birth to offspring and to live long enough to raise them until they are capable of independent living, which is basically 30 years or so, and for the majority of our existence, that is exactly what we did. Now with improvements in medicine and standards of living (including food availability, shelter, cleanliness, etc, etc), we can live 2-3x as long, if not more. What helps us early in life ends up killing us later on, but this is "genetically" unimportant. Modern lifestyles work against our biology, which includes the genetic mandate to eat, eat, eat. This is the root of the problem, not some abstract concept of "laziness."

Makes a lot sense ...and couldn't agree more on the relatively non-significant role ( if any ) laziness has to do with obesity.

As far as how much does metabolic type vary, the truth is that most studies show that it's not much from person to person, if I recall...however, it's also important to look at subject populations, too: syudies also show differences in the way that obese individuals actually utilize the calories that they consume vs. lean individuals, even when taking into account activity levels or influences of obesity itself (i.e. type II diabetes).

Again, makes a lot of sense. Perhaps there is some merit in what I sometimes see referred to as a myth. Namely, that obese people don't eat more than non-obese people. For example......

Myth 4: Obese people eat more than non-obese people

By 1979, 19 studies had already found that obese people eat the same or less than thin and normal weight people. Recent studies published in the American Journal of Clinical Nutrition and the Journal of Applied Behavioral Analysis confirm these findings. Obesity is multi-determined, and eating is only one of the factors affecting one’s weight. Genetics, endocrine function, activity level, lifestyle, medications and metabolism all play a role in determining a person’s weight.​

...wish I knew which 19 studies they were referring to above . I think it would seem rather counter intuitive to most people that ' obese people eat the same or less than thin and normal weight people '.

Early reports of "50 calories/day" additional BMR per pound of muscle estimates have been lowered considerably, to around 7-12 kcals/pound of muscle per day. Meaning if I start working out today and put on an additional 20 pounds of muscle in a year, I have only increased my BMR by around 150-200 calories/day, which is barely significant (that's roughly one extra banana a day...of course, energy requirements needed to sustain the work levels that i will need to build that muscle will be greater too, which is why active people need to eat substantially more). However, the sum total of genetic factors (not just BMR due to muscle type, distribution, and amount but actual chemical/hormonal factors, neuromuscular efficiency, psychological brain chemistry, blah, blah, blah) might make this more significant, too.

And maybe a case where the whole is greater than the sum of its parts

Like G said, we don't know to what effect any of this will play on any specific individual; however, like I was trying to say, by knowing that these are real factors and not just laziness, we are able to not only better understand why an individual might be having difficulty with their efforts but to be able to better tailor our own efforts in helping them through their difficulties. It's easy to label someone as being lazy. It's also counter-productive and won't help anyone that is attempting an honest lifestyle change having real issues that go beyond a simple issue of motivation.

Couldn't agree more.

I think distilling the underlying issue / major cause of obesity down to something like ' laziness ' represents a rather simplistic, naive and short sighted view - and trivializes obesity to some extent as well.

 

[Nicolasd]

Myth 4: Obese people eat more than non-obese people

By 1979, 19 studies had already found that obese people eat the same or less than thin and normal weight people. Recent studies published in the American Journal of Clinical Nutrition and the Journal of Applied Behavioral Analysis confirm these findings. Obesity is multi-determined, and eating is only one of the factors affecting one’s weight. Genetics, endocrine function, activity level, lifestyle, medications and metabolism all play a role in determining a person’s weight.

Blah, they're done without factoring in activity levels. The activity factors are fairly large - you can easily burn 20% more because of your activity level. If I went from my maintenance at 2500 kcal, to 3000 kcal, without any weight training and proper nutrition to ensure some of it ended up as muscle, and stuck to that for several years without cutting, I'd surely end up obese. And that's much less than the difference between "sedentary" and "moderately active" in the Harris Benedict formula.

Also, many obesity studies were done by having people self report their eating. Many obese people eat 50 to 100% more than they self report, often without being conscious about it.


And bipennate, you're a fountain of facts

 

[Wrangell]

Blah, they're done without factoring in activity levels.

When they suggest ' obese people eat the same or less than thin and normal weight people ' I can only assume they must have controlled for activity levels when arriving at this conclusion. Otherwise I suspect the results would be somewhat confounded.

The activity factors are fairly large - you can easily burn 20% more because of your activity level. If I went from my maintenance at 2500 kcal, to 3000 kcal, without any weight training and proper nutrition to ensure some of it ended up as muscle, and stuck to that for several years without cutting, I'd surely end up obese.

Perhaps, but i can only assume that the claim that ' obese people eat the esame or less than thin and normal weight people ' is based on ' all other factors being equal ' - such as activity levels.

If a non-obese person or an obese person goes from 2500 kcal, to 3000 kcal etc. etc. I suspect they should both expect the same outcome in terms of eventual fat gain. Unless of course, obese people gain fat in a different way or rate than non-obese people do.

And that's much less than the difference between "sedentary" and "moderately active" in the Harris Benedict formula.

I suspect that applies whether a person is obese or not obese.

Also, many obesity studies were done by having people self report their eating. Many obese people eat 50 to 100% more than they self report, often without being conscious about it.

I can't comment on ' self-reporting ' as I don't know exactly which 19 studies they were referring to and the types of methodologies that were employed in each of the studies.

However, they suggest that the notion of that ' obese people eat the esame or less than thin and normal weight people ' has also been confirmed in recent studies ....." recent studies published in the American Journal of Clinical Nutrition and the Journal of Applied Behavioral Analysis confirm these findings ".

 

[sig]

Adding to the fray

Sorry, I don't have the materials with me where I saw this in the first place, but to add to the studies above, I can't help but think of the in-patient studies, where they strictly control the calories and activity levels of people with normal weight (some who deliberately gained weight for the experiment too) and people who are obese. Given such rigid control that is not available in real world situations, the scientists were able to make ANYONE lose weight. However, they also noticed significant differences in caloric needs and metabolism between the groups, suggesting that there are elements of obesity that are difficult to overcome, even if you eat a highly restricted diet and increase your activity level.

The truth, though, is that there is so much about this that we still don't know.

When I measure my calorie levels and aim for a particular deficit, I do so with the knowledge that all my calculations are RELATIVE, not ABSOLUTE.

I have no idea how many calories I truly burn. None of us do. We can estimate based on personal data and our general knowledge. But we don't really know what our metabolism is.

We also keep imperfect calorie logs. Even using the best software and meticulously recording everything, we are using AVERAGES about what our food nutritional composition is, how accurate we are at measuring portions (or companies are!), and so forth.

The most accurate data we have is the ability to measure the result. Have you lost weight? How much? Can you measure the body composition change?

So, then we take our result and work backwards, using our data to see what kind of deficit (or gain) we were keeping. I assume that as long as I am internally consistent with my methods of estimating my food, estimating my activity, then I can duplicate my results in the future, by keeping to these same sets of relative standards. If I'm not happy with my results, I can adjust the inputs - the food or the activity or both - until I achieve the results I like. If I've produced a deficit of 250 calories per day, for example, it doesn't matter if I believe it is happening at 2000 total calories a day, 2250 or 2500, so long as I continue to match the same levels.

However, let's say I'm aiming for 2000 calories (hypothetically) and someone else here is doing the same. We both might be achieving the same deficit or gain results, but I highly suspect that we'd see a real difference if we "traded" lives. Meaning - if I prepared all the food that I believe is MY 2000 calories and you prepared all the food you think is YOUR 2000 calories, and if I set up YOUR training program and you set up MINE...

...I am willing to bet that we do not achieve the same results. Our nutrition and training and activities are far too subjective to our own estimates. Somewhere, buried in the estimates, is some idea of how your metabolism works. It matters, of course. But I suspect that for the average person (rather than the extreme outliers), the difference in metabolism is negligible compared to all the other 'noise' in those estimates.

The upshot? It's pointless to compare yourself to anyone else or worry about metabolic differences. Keep at it until you find what works for you, based on your own best data and observations, and work from there.

 

[matt182]

The truth, though, is that there is so much about this that we still don't know.

When I measure my calorie levels and aim for a particular deficit, I do so with the knowledge that all my calculations are RELATIVE, not ABSOLUTE.

I have no idea how many calories I truly burn. None of us do. We can estimate based on personal data and our general knowledge. But we don't really know what our metabolism is.

We can use direct caloriemetry

 

[Nicolasd]

When they suggest ' obese people eat the same or less than thin and normal weight people ' I can only assume they must have controlled for activity levels when arriving at this conclusion. Otherwise I suspect the results would be somewhat confounded.

Perhaps, but i can only assume that the claim that ' obese people eat the esame or less than thin and normal weight people ' is based on ' all other factors being equal ' - such as activity levels.

You'd be surprised at how often stuff like that somehow gets overlooked. There is both a lot of very poor science being done, and a lot of good science being referred poorly. Some scientists aren't very smart, others take shortcuts to get more interesting findings, others have an agenda to push and bend facts or fail to tell the whole picture. They're just people. In general, the peer review system catches this - but the studies are often referred in the media before the peer review, and many unashamedly refer studies that failed the peer review afterwards to sound interesting.

And the picture just becomes more muddy when you have the media and organisations who want to publish interesting stories or have an agenda to tell you about the studies.

Those studies could easily have been done correctly, but then misrepresented to let that center write interesting myth debunks.