Do carbohydrates promote weight gain?

viviennem

edit to add: If carbs don't get converted to fat, how come cattle, sheep and pigs are fed high grain diets to "finish" them to a sale weight?

Click to expand...

The quick answer is that we aren't these animals
As Mark Hellerstein says

Bees make wax (lipid) from honey (carbohydrate). Pigs fatten on a grain diet. .

Click to expand...

But

Most experimental data in humans, however, contradict this view of the function of de novo lipogenesis. Initial studies in which indirect calorimetry was used showed little or no net de novo lipogenesis after short-term carbohydrate overfeeding (1). Subsequent isotopic studies confirmed the absence of quantitatively significant flux through hepatic de novo lipogenesis under most conditions of carbohydrate energy surplus

Click to expand...

In the hierarchy of fuels, dietary carbohydrate appears to have a higher priority for oxidation than does dietary fat; when both are present, carbohydrate is chosen.

Click to expand...

These questions and more arise from the observation that de novo lipogenesis is the pathway of last resort and that, at least regarding converting carbohydrates to fats, humans are neither bees nor pigs

Click to expand...

However it is also true that if if you eat excess calories for you then the glucose will be used first and the fat will be stored as fat. (ie in the most energy efficient way, it costs energy to convert carbs to fat )

First, these results do not mean that extra carbohydrate energy represents “free” energy in terms of body fatness. By sparing fat in the body's fuel mixture, surplus carbohydrate energy will make people fatter, even though it is not directly converted to fat.

Click to expand...

That's what Hellerstein describes as the normal scenario
ie that normally excess carbohydrate is stored as glycogen and only converted to fat as a 'last resort'.
If glycogen stores are full then the excess has to go somewhere and may be converted to fat and stored in the organs particularly the liver
Professor Taylor (Newcastle diet) describes this scenario in his Twin cycle Hypothesis. Which is why his diet aims to 'defat' the liver.
http://onlinelibrary.wiley.com/doi/10.1 ... .12039/pdf

There is also some evidence that people with muscle insulin resistance have an altered pattern of fuel use. Whilst those with normal muscle insulin sensitivity store an extra carb load as glycogen in the muscles, those with insulin resistance muscle store less as glycogen and convert more excess carbs to fat in the liver.
(I think this could be cumulative and a vicious circle since fat in the liver causes hepatic insulin resistance we then have the Prof Taylor scenario).

Heres one study with young men

Following ingestion of two high carbohydrate mixed meals, net muscle glycogen synthesis was reduced by ≈60% in young, lean, insulin-resistant subjects compared with a similar cohort of age–weight–body mass index–activity-matched, insulin-sensitive, control subjects. In contrast, hepatic de novo lipogenesis and hepatic triglyceride synthesis were both increased by >2-fold in the insulin-resistant subjects.

Click to expand...

http://www.pnas.org/content/104/31/1258 ... f_ipsecsha
In another study of otherwise healthy older people with muscle insulin resistance (through ageing) researchers found that they converted more of the excess from carbohydrate intake to liver fat than did younger people with normal muscle insulin sensitivity.
http://www.ncbi.nlm.nih.gov/pubmed/22829450
Young but insulin resistant men were found to have 30% lower de novo lipogenesis in the liver when they ate excess carbs after a bout of exercise (which in creased their muscle insulin sensitivity). http://www.pnas.org/content/108/33/1370 ... f_ipsecsha
There are lots of similar studies.
These studies don't necessarily address the question as to why some people are more muscle insulin resistant than others,
Better stop. Got carried away again and have to do the hoovering.
:lol: :lol: :lol:

stoomc said:

If you are gaining weight over 150g of carbs then you are going over caloric maintenance or are seeing extra water/ glycogen weight. As the link abov states- carbs do not directly make you fat (only via de novo lipogenisis- which is very rare) carbs make you fat by burning carbs instead of fat... However, if you are eating at maintenance (or below) this is nothing to worry about.
As I stated before though, I am not going to preach a high carb diet on a diabetic forum, that would be silly! I was just sharing the conclusions from various people that were very kind to get back to me via email yesterday (and a few more coming through today from some more, which I am very surprised about!)

I would also like to hear how many carbs on average everyone here is eating- if there is another thread discussing this, I apologise!

Thanks.

Click to expand...

Actually I do count the calories of everything I eat/drink every day, as well as the sugars and the Calories. So I know for a fact this weight issue is not due to any increase in calories.

To illustrate.. my total calories per day are always a maximum 1500 (give or take 10 cals!). This is, according to Basal Metabolic Rate/weight loss calculators, the ideal amount of cals for my height/weight in orer for me to lose a healthy 2lbs per week.

I know my calories are steady and well controlled, regardless of carbs intake. Yesterday, for example, I had 1328 Calories, 139.16g Carbs. Monday I had 1506 Calories, 116.37g Carbs. prior that, was 1509 calories, 142.16g Carbs.

as you can see, I eat up to 150g carbs daily, so am not a real LCHF dieter, but I know that (for me anyway!) <150g daily carbs is 1. a heck of a lot less carbs than I ate when doing Low Gi diet for 10 years and 2. the max carbs I can take if I want to maintain or lose weight 3. The max daily carbs i can eat if I want to keep decent BG/HbA1C levels. But then again, everyone's body and metabolism and diabetes levels are different. What works for me might not work for others, and vice versa.


Edited: just seen the above post re: Insulin resitant muscles and fatty liver, interesting, as I was recently diagnosed with fatty liver, even though I don't drink alcohol, and have always watched my fat intake due to strong family history severe heart problems!

World Hereafter said:

hi Sid, would you mind letting us know how many carbs you eat, roughly per day? Especially interested in how many you ate when you were losing the weight? Many thanks!

Click to expand...

Hi W H, I was diagnosed and put straight on insulin treatment, I was around 18.5 stone (260lb) in weight and told that I would probably need to use insulin for life but if I lost weight and improved my insulin resistance there was a chance that I might be able to reduce it or even possibly come off it. That was my motivation to lose weight and by carefully matching my insulin to my carbs and drastically reducing the amount of food I ate I lost a little under 4 stone in around 6 or 7 months. During this time and up till the time I stopped insulin treatment a year after diagnosis I was eating around 60g to 80g of carbs a day.

After coming off insulin I started to add more carbs back to my diet whilst all the time watching my bg levels and never allowing my HbA1c to go out of the 5%'s. (it was 12.6% at diagnosis) I have never counted calories, fat or protein and stopped counting carbs as well after I stopped using insulin, I couldnt see the point of carb counting for the sake of it, as long as my bg levels remained stable I saw no benefit in actual counting of carbs. But I would estimate my current carb intake at around 120g to 160g a day sometimes a little less and sometimes a little more.

I now weigh (this morning) 13 stone 2 lbs (184lbs) so have lost a total of around 5.5 stone in four years. I have also just reduced my Metformin to two tablets a day from the max dose I have been on for the last four years. My cholesterol taken on 4th Jan is 4.7 my HDL is 1.8, and my cholesterol HDL ratio is 2.6.

I would still go straight into double figures if I ate my old diet of white bread, sweets, chocolate and huge portions of everything but over the last four years I guess I have re wired my brain into a different way of thinking when it comes to eating so I am not constantly snacking and am full up after eating much less food. I now eat to live but still very much enjoy my food.

Hi all. I've read the link to Lyle about fat 'never' causing weight gain (the article and the comments do go on a bit!). I can understand and agree with much of it but my simple brain asks the question 'if I'm sedentary as many people are today and consume society's excessive carb level, my body will have used carbs instead of fat for energy (ref Lyle) but still have a lot left over, so what happens to that?'. I guess it is converted to glucose and then stored as glycogen, but as the body's stores will already be full of glycogen as we don't exercise enough so.....it's gets stored as fat in the liver as Lyle says as an exception. Am I right in thinking that he misses the fundamental point that many of today's obese are probably in the exception area and that as a result carbs DO increase weight as there is no-where else for them to go? Can I ask Sid and others who understand this better than me where has my thinking gone wrong?

Thanks, Phoenix, for your usual detalied answer - where do you get all this information from?

Unfortunately - as I said, I'm no scientist. I can just about translate "de novo lipogenesis" from Latin and Greek (which doesn't tell me what it means!), but you pretty well lost me with the rest. I think my answer was almost the same, except that it was extremely simplistic - it missed out the bits about preferred storage of excess glucose and went straight to putting it in the fat cells, which I understand from your post is the last resort.

This doesn't alter the fact that, on 1000 cals per day, most of them from carbohydrates, I managed to gain weight - even though I was then (and had been for a while) walking 3 miles per day with my dogs.

Sadly for research purposes, I have never been a healthy young man. I think I'm probably closer to a pig - an omnivore by dentition and preference, with a sparse hair pattern and a skin that sunburns easily! :lol: and both of us get fat on carbohydrates.

I just wish occasionally that "they" would do research on middle-aged women and extrapolate the results to cover the rest of the population. :wink:

Viv 8)

Daibell said:

I've read the link to Lyle about fat 'never' causing weight gain (the article and the comments do go on a bit!).......................
Can I ask Sid and others who understand this better than me where has my thinking gone wrong?

Click to expand...

All I can say is that from my own observations when ever I have increased my fat intake I put on weight so I would take Lyles remarks with a huge pinch of salt, I know that fat causes weight gain because it happens to me every year in the run up to xmas when we buy lots of cheese, Stilton, Port Salut, Brie etc and every year after eating cheese after my evening meal for a week or so I put on weight.

I find it ridiculous to hear that anyone would say that increased fat intake will not aid weight gain, surely any calorific increase will aid weight gain and fat has more calories than any other food group. I would say its fairly obvious, and is the reason I regularly put on a few pounds when I eat more cheese. Perhaps you have taken his words out of context if not then I doubt many people would agree with him. I know a lot of people who advocate LCHF will say things like that but it doesnt ring true for me I'm afraid which is why I do not add any fat to my diet, I get quite enough already without any need to add any extra.

I really love Stilton but rarely eat it now because I know it makes me put on weight. Its a once a year treat for me now and I know that I will have to pay for it and spend a few weeks being ultra careful with my diet to get rid of the "cheese pounds".

I find both carbohydrates and fats cause weight gain as the mor insulin you take the more weight you are likely to pu on. I find the fats the worst, cheese, milk,etc., so avoid them most of the time. I am a redhead and we seem more likely to put on weight as a group but do not know if any research has been done into this?

I think that Daibell may have made a typo?!
Lyle McDonald says

1.Carbs are rarely converted to fat and stored as such
2.When you eat more carbs you burn more carbs and less fat; eat less carbs and you burn less carbs and more fat
3.Protein is basically never going to be converted to fat and stored as such
4.When you eat more protein, you burn more protein (and by extension, less carbs and less fat); eat less protein and you burn less protein (and by extension, more carbs and more fat)
5.Ingested dietary fat is primarily stored, eating more of it doesn’t impact on fat oxidation to a significant degree

Click to expand...

Here's his summary
1.Excess dietary fat is directly stored as fat
2.Excess dietary carbs increases carb oxidation, impairing fat oxidation; more of your daily fat intake is stored as fat
3.Excess dietary protein increases protein oxidation, impairing fat oxidation; more of your daily fat intake is stored as fat

Got it? All three situations make you fat, just through different mechanisms. Fat is directly stored and carbs and protein cause you to store the fat you’re eating by decreasing fat oxidation

Click to expand...

thanks for answering SidBonkers.. and sorry for delay in replying!

Congrats.. that's brilliant progress in a short space of time, and you must be so pleased you made those changes :thumbup:

When you guys say you hold to the laws of thermodynamics, which law do you mean? I paraphrase them here; the first law states that total energy in a CLOSED system remains constant [ humans are NOT "CLOSED systems"] so for us it doesn't apply. The second states that entropy must always increase in a chemical reaction. If the second law is applied, then it follows that calories are used differently according to the chemistry they follow. Hence "A Calorie is a Calorie" within a living system modified by enzymes contradicts the second law. [ enzymes reduce activation energy for reactions and necessarily are different for different reactions.
Read Feinman on that subject, but brush up your undergraduate physics first. Note Calorie means kilocalorie. A calorie is that amount of energy which raises the temperature of 1cm cubed of pure water by 1 Celsius degree. Not much energy at all. You eliminate many calories from your system every time you visit the loo
and Taubes understands physics, His is a high quality engineering degree. He's also an excellent writer!
Hana