Why carbs can turn your liver into foie gras

It’s funny how things seem to come in threes, and this week was an example of this maxim in that I saw three patients all of whom had deranged liver function tests. All of them had raised levels of at least two liver ‘enzymes’. This, in medicine, is generally taken as a sign of damage to the liver. While there are lots of reasons for why liver enzymes may be raised, our first thought in medicine is usually to ask about alcohol consumption. None of these individuals was abstemious, but at the same time none of them had alcohol consumptions that could be described as excessive.

When I see individuals with deranged liver function who do not drink much alcohol, my next thought is usually their diet. And in particular, I start thinking about whether they may have a touch of ‘metabolic syndrome’. This condition, characterised by excess weight around the middle of the body, is common, and tends to be a sign of an excess of carbohydrate and therefore insulin in the body. Insulin promotes fatty production in the body, and some of this can end up being dumped in the liver. As a result, liver function can become deranged, and if the problem persists, it may eventually lead to a condition known as ‘fatty liver’.

As it happens, each of the three patients I saw this week were carrying excess weight around their middles. My advice to them was to get control over blood sugar and insulin levels. Basically, that means eating less carb, particularly those carbs that tend to cause most disruption in blood sugar and insulin levels including bread, potatoes, rice, pasta and breakfast cereals.

I was reminded about these three patients today on reading a study published yesterday in the journal Gut [1]. In this study, Swedish researchers took a group of adults (average age 26) and put them on a regime which involved limiting their physical activity and getting them to eat two fast food meals each day for four weeks. The participants were monitored in term of, among other things, liver function and weight. Their results were compared with a group of individuals who were not subjected to the regime (these individuals acted as ‘controls’).

Over the course of the 4-week study, those on the fast-food regime put on an average of about 6.5 kg in weight. In particular, waist size increased significantly. The level of the liver enzyme known as ALT (alanine aminotransferase) went up from an average of 22.1 U/L (normal) to 97.0 U/L (abnormally raised). This would be taken, generally speaking, as a sign of liver damage. Not only that, but the fat level in the liver cells of these individuals increased by over 150 per cent. One of the 18 participants developed full blown fatty liver (quite a feat in just four weeks of unhealthy eating).

The findings of this study are reminiscent of Morgan Spurlock antics in the film ‘Supersize Me’. His one-month fast food diet experiment led to significant derangement in his liver enzymes.

So, perhaps not surprisingly, fast food turns out to be bad for our weight and liver. But what was interesting about this study is that the authors looked at the relationship between different elements of the diet and changes in ALT levels. In other words, they wanted to see if they could find out what it was about fast food that seemed to damaged the liver.

Here’s what they found:

Intake of FAT was NOT associated with ALT levels

Intake of PROTEIN was NOT associated with ALT levels

Total CALORIE INTAKE was NOT associated with ALT levels

Intake of CARBOHYDRATE WAS associated with ALT levels

Rather oddly, the authors conclude that this shows that raised liver enzymes can be caused by not just alcohol, but also sedentary behaviour and higher than usual caloric intake. I don’t know why the authors felt the need to draw conclusions that were not supported by their data: remember, it was not an excess of calories that was associated with deranged liver function, but an excess of carbohydrate.

Those of you who watched Supersize Me may remember that the doctor who was keeping a medical eye on Morgan Spurlock at one point told him that his diet was causing his liver to turn into foie gras. The evidence from this study suggests that it was not mere overindulgence nor a high intake of fat that was responsible for the fatty degeneration of Morgan’s liver, but a glut of carbohydrate in this diet.

Any of you wanting to remember that it’s carbs that cause fatty deposition in the liver can do this contemplating the making of foie gras. What is it that geese are force-fed to turn their livers into something that is mainly fat? The answer, of course, is grain.

References:

1. Kechagias S, et al. Fast-food-based hyper-alimentation can induce rapid and profound elevation of serum alanine aminotranferase in healthy subjects. Gut 2008 [epub Feb 14th]

22 Responses to Why carbs can turn your liver into foie gras

  1. Esther Oppenheim 15 February 2008 at 5:11 pm #

    I have just read the article in ” GUT” ( available free on their website)
    Carbohydrate intake was correlated with rising ALT (a liver enzyme), not with increased fat in the liver, and started returning to normal before the subjects returned to normal diets. They postulate that the raised liver enzyme is not a sign of liver ill health but of enzyme induction by being presented with a large load. Increased fat in the liver which may be a sign of liver disease.was correlated with overall intake of calories,

    I think it is a step too far to conclude from this study that carbohydrates alone were responsible for anything other than a clinically insignificant change in a liver enzyme.

  2. Dr John Briffa 15 February 2008 at 5:27 pm #

    Esther
    On what basis do you conclude that the rise in ALT levels was ‘clinically insignificant’? The authors themselves state that ‘most participants developed PATHOLOGICAL [emphasis mine] ALT levels during study’

  3. gallier2 15 February 2008 at 5:30 pm #

    Just a bit of trivia concerning foie gras. Nowadays the geese are stuffed mostly with corn (maize) but historicly in roman times (yes the romans enjoyed already foie gras) figs were used for that purpose. The word foie in french derives from it.

  4. Anna 15 February 2008 at 5:57 pm #

    I can’t help but wonder if it was the High Fructose Corn Syrup portion of the carbohydrate intake that was most responsible for the increase in ALT and liver fat, since fructose goes to the liver to be metabolized, unlike glucose. Many fast foods have HFCS as an ingredient: non-diet carbonated beverages, catsup, mayonnaise, etc. The content in a full meal could be quite high.

    What alarms me even more is increase in use of agave syrup (or nectar) as a “low-glycemic” and “natural” sweetener by those wishing to avoid HFCS and refined table sugar. Very few seem to realize that agave syrup is as much as 92% fructose, depending on brand, which could put a terrific load on the liver if used liberally. I have seen a huge increase in the availability of bottled agave syrup/nectar and processed food products sweetened with agave syrup at the “natural” and “health” food stores. Additionally, lots of health-oriented bloggers have been indicating they use this “healthy” sweetener, perhaps liberally, since the the low-glycemic factor or “raw” claims give the appearance of being a better sweetener. But I think that claim is questionable, given the extremely high concentrated fructose factor. There is nothing natural about overloading the liver with concentrated fructose.

  5. caliwag 15 February 2008 at 7:46 pm #

    Does this leave me OK with my breakfast of organic porridge oats (made with goat’s milk), dried fruit, linseeds, a few pumpkin seeds and a dob of borage honey?

    If you tell me this is appalling, I’m going to kill myself, if nothing because of the washing up, or the fact that I’d rather eat a bacon butty!! Jeez

    Actually I feel great on the above…slow energy release and all that.

  6. Chris Highcock 15 February 2008 at 8:24 pm #

    Excellent post Dr, as ever.

    Over at Hyperlipid,

    http://tinyurl.com/2dwf8l

    Peter has pointed out that the other interesting thing about the study was that it found that healthy HDL cholesterol actually increased over the four-week period.

    It is crazy how this was reported – all the newspapers have said that it proves that fat is bad for you when it says nothing of the sort.

  7. maja 15 February 2008 at 10:06 pm #

    Towards the end of my pregnancy they did some blood tests at the hospital and I had high liver function for a while and they never found out why.
    I was on low GI diet before I got pregnant because I have pcos but the diet went out of the window throughout the pregnancy and I had a lot of sweet treats and bready stuff. Maybe thats why my ALTs were off the scale???

  8. S Wilkins 17 February 2008 at 12:41 pm #

    I am sure Dr Briffa is spot on. On a previous info reference a supressed report re. a cholesterol lowering product – opur GP rang my husband two weeks after I had read the whole report, to tell him to stop taking the drug. He already had.

  9. Tiggy 18 February 2008 at 2:53 am #

    There are established links between insulin resistance and a fatty liver and excess carbs can lead to insulin resistance. The problem is in establishing what is an excess of carbs and to what degree low GI carbs are ‘safe’.

    You still hear dieticians recommending pasta as a key part of a healthy diet. I know someone morbidly obese whose dietician told her to eat pasta and she’s not lost any weight because she eats huge plates of white pasta with sugary processed sauces.

    Hmm, can anyone translate post no. 8?

  10. Margaret Ranken 18 February 2008 at 5:52 pm #

    Farmers swear that producing Foie Gras isn’t cruel because the geese come running to have the grain poured down their throats. We’re doing the same thing as we enthusiastically stuff all those croissants and cornflakes and pizzas down. I’m guessing it’s down to the feel good sensations that carbs create by producing serotonin in the brain.

  11. Neil 18 February 2008 at 8:17 pm #

    Apparently, geese don’t have a ‘gag reflex’ so the force feeding is not so forceful as it would be for a human. Still makes me shudder to look at it, but on the other hand the geese don’t seem too perturbed.

  12. Ulf_S 19 February 2008 at 12:24 pm #

    Tiggy, post 8 is from a Swedish lowcarb blog. The text basically says that dr Briffa has commented the study and links to here, nothing more exciting than that…

  13. simona 22 February 2008 at 2:55 pm #

    ‘particularly those carbs that tend to cause most disruption in blood sugar and insulin levels including bread, potatoes, rice, pasta and breakfast cereals.’
    In your blog you mention rice and pasta as high GI foods. According to Jennie Brand-Miller there are some types of rice, like japanese rice or basmati, that do not have a high GI and pasta does not have a high GI either. I agree that these foods should not form the basis of the diet in the way the ‘nutritional pyramid’ is presented nowadays, but I do not think it is correct to put all these carbs in the same group.

  14. Dr John Briffa 22 February 2008 at 3:11 pm #

    Simona
    I’m actually not the bothered about the GI, it’s the glycaemic load (GL) that I believe is more important. And the reality is that because of the quantity in which they tend to be eaten, rice (even basmati, say) and pasta tend to have high GLs.
    Plus, the nutritional value of a food is not just determined by a food’s GI/GL, but other things too including the nutrient density of the food. Here, grains (including rice and pasta) come up short, generally speaking, compared to, say, fruits and vegetables (other than the potato).
    For these reasons, I believe elevating certain varieties of rice and pasta solely on the basis of their GIs would be quite misleading.

  15. Neil 24 February 2008 at 6:54 pm #

    Does glucose have a GL? Or has that not been calculated?

  16. Dr John Briffa 24 February 2008 at 7:08 pm #

    Neil
    Not to my knowledge. The GL depends on the size of a ‘portion’ of food, and people don’t eat ‘portions’ of glucose. So I suspect for these reasons, glucose doesn’t have a GL as such.

  17. Madeleine 31 March 2010 at 3:45 am #

    In terms of GI, Gary Taubes has a great chapter in his Good Calories, Bad Calories. Glucose goes straight into the blood (only 30-40% pass to the liver), causing a high insulin response (high glycemic) and is used as fuel; excess glucose is converted to fat and stored. Fructose passes directly to the liver to be metabolized instead, so has a low GI, but the liver converts it to triglycerides to be stored as fat. Thus while glucose leads to chronically high insulin levels (producing a myriad of problems, obviously), more fructose consumption leads to higher triglycerides in the blood and more fat storage. Further, fructose apparently blocks the metabolism of glucose in the liver as well as the synthesis of glucose into glycogen. Consequently, the pancreas secretes more insulin to overcome the excess glucose at the liver, and muscles thus compensate by becoming more insulin resistant.

    So either way, insulin resistance is the result of a high-carb diet. There are no carbs that are “better” than others in my opinion. (Fiber has it’s own set of problems…)

    As for pasta and rice, I don’t know anything about basmati or other types of supposedly healthier rice, but most starches are made up of long-chain glucose molecules that produce high insulin response. I’ve never heard of pasta that does not have high GI.

  18. Madeleine 31 March 2010 at 3:51 am #

    Also, I forgot to mention, anything that’s not glucose will lower the GI. That’s why ice ream, which is full of fat as well as sugar, has a much lower GI (36) than white bread (69) and white rice (72) among other starches.

  19. rose 6 February 2012 at 12:41 am #

    I dont think geese are meant to eat alot of grains, I know my horse I had once developed tying up syndrome because I was feeding her grain and she wasnt getting enough exercise. the vet gave her vita e and selenium. it cured her and I started to give her plain oats. she loved it with molasses and she never gained weight or suffered tying up again.

    as for fatty liver if your glucose intolerant and the cells cannot take up glucose (due to nutritional deficiencies like vita d low calcium absorption due to low fat eating) it would make sense the liver would accumulate fat around itself on purpose. it needs a steady source of energy when it can’t access fat from teh adipose tissue due to high insulin levles. we know that high insulin levels prevent fat from being released into the blood stream and causes fat there to go back into adipose tissue. so I read. this way it can feed off the fat it has stored within itself, works for the heart too.

    also cytokines are associated with fat mass size, but did it ever occure to anyone that cytokines don’t come about because your fat, but because those fat cells are sick from having to convert all that sugar to fat to get it out of the blood and so the cells can use the fat? sugar causes glycation and damages vital proteins, hence the immune response.

    we need plenty of minerals (is sulfer a mineral?) and vitamins to handle glucose properly considering it is very oxidative, like gasoline if you ask me. explosive when exposed to oxygen and catalysts.

    sugar really is not the problem, people tend to high gi foods but high gi foods are devoid of nutrients hence they is why they are high gi. the more nutrtious something is the lower on the gi it is. whole fresh fruits are lower in gi then cooked processed fruits in a can or juiced. while I can eat raw honey with apple cider vinegar, which lowers the gi even more, I wouldnt ever try that with corn syrup, yuck!! my mom used to use plain ole corn syrup I remember her using when cooking. it is amazing how much you can remember when a kid.

    rose

Trackbacks/Pingbacks

  1. Linköpingsstudien kommenteras av Dr Briffa « Low-carb-bloggen - 16 February 2008

    [...] som visar att kolhydratrik kost påverkar levern negativt (fettlever) har kommenterats på Dr Briffas blogg. Inlägg och kommentarer är [...]

  2. Mark’s Daily Apple » Blog Archive » Study Suggests Carbohydrate-Rich Diet, Obesity Linked to Esophageal Cancer Risk - 26 February 2008

    [...] Dr. Briffa: Why Carbs Can Turn Your Liver into Foie Gras [...]

  3. Hepatitis C Research and News: Liver disease: ‘50% of rural population hepatitis C positive’ | Cunning Hugh Cool Website - 30 June 2013

    [...] In other words, they wanted to see if they could find out what it was about fast food that seemed to damaged the liver. Heres what they found: Intake of FAT was NOT associated with ALT levels Intake of PROTEIN was NOT associated with ALT levels Total CALORIE INTAKE was NOT associated with ALT levels Intake of CARBOHYDRATE WAS associated with ALT levels Rather oddly, the authors conclude that this shows that raised liver enzymes can be caused by not just alcohol, but also sedentary behaviour and higher than usual caloric intake. I dont know why the authors felt the need to draw conclusions that were not supported by their data: remember, it was not an excess of calories that was associated with deranged liver function, but an excess of carbohydrate. Those of you who watched Supersize Me may remember that the doctor who was keeping a medical eye on Morgan Spurlock at one point told him that his diet was causing his liver to turn into foie gras. The evidence from this study suggests that it was not mere overindulgence nor a high intake of fat that was responsible for the fatty degeneration of Morgans liver, but a glut of carbohydrate in this diet. Any of you wanting to remember that its carbs that cause fatty deposition in the liver can do this contemplating the making of foie gras. For the original version including any supplementary images or video, visit http://www.drbriffa.com/2008/02/15/why-carbs-can-turn-your-liver-into-foie-gras/ [...]

Leave a Reply